ChemWiki - User contributions [en]

It:DDT

2006-11-17T11:49:34Z

Kfl05:

==='''Introduction'''===
DDT is arguably the best known organic pesticide, which was developed as the first of the modern insecticides early in World War II.It is a highly hydrophobic colorless solid with a weak, chemical odor that is nearly insoluble in water but has a good solubility in most organic solvents, fat, and oils. It was initially used with great effect to combat mosquitoes spreading malaria, typhus, and other insect-borne human diseases among both military and civilian populations, and as an agricultural insecticide.

{| class="toccolours" border="1" style="float: right; clear: right; margin: 0 0 1em 1em; border-collapse: collapse;"
! {{chembox header}}| '''DDT'''
|-
| align="center" colspan="2" bgcolor="#ffffff" | [[Image:DDT1.png]]
|-
| [[IUPAC nomenclature|Chemical name]]
| ''4,4'-(2,2,2-trichloroethane-1,1-diyl)bis(chlorobenzene)''
|-
| [[CAS nummber]]
| 50-29-3
|-
| [[Chemical formula]]
| {{{formula|C14H9Cl5
|-
| [[Molecular mass]]
| {{{mol_mass|354.49 g/mol
|-
| [[Melting point]]
| 108.5 °C
|-
| [[Boiling point]]
| 260.0 °C
|-
| [[Simplified molecular input line entry specification|SMILES]]
| {{{SMILES|[ClC(Cl)(Cl)C(C1=CC=C(Cl)C=C1)C2=CC=C(Cl)C=C2
|-
| [[Colour]]
| {{{Colour| colorless
|-
|}

File:DDT1.png

2006-11-17T11:45:00Z

Kfl05:

File:DDT.png

2006-11-17T11:37:36Z

Kfl05:

It:projects

2006-11-17T11:27:01Z

Kfl05: /* Supplemental Project Page */

__FORCETOC__

'''''You MUST use the Edit buttons on the right to edit this content. Do NOT use the Edit button on the top of this page.'''''
== Sandbox (Play-Pen) ==

This is an area where you can play without worrying what you do. Enter it by pressing the [Edit] button '''on the right''' and '''not''' at the top. Go here for a [http://en.wikipedia.org/wiki/Wikipedia:Cheatsheet ''cheat sheet''] summary of how to create a Wiki page. It's a free-for-all in here! Learn how to use a Wiki by coming here! PS This is how to do Greek: Α, α, β Δ, δ
Try copying/pasting some of the [http://www.ch.ic.ac.uk/local/it/lab1.html examples in the course work] into this page. See the effect by selecting '''Show Preview'''. No not use '''Save Page''' so as to leave this area uncluttered for others.
----

== Main Project Page ==
'''Please do not edit this page itself'''. Click on one of the titles to start editing.
{| summary="CIT Project Titles" border="1"
! bgcolor="cyan" |Project Number
! bgcolor="cyan" |General Keywords
|-
| bgcolor="#CCFF00" |01
| bgcolor="#CCFF00" | [[it:Lignocaine|Lignocaine (used in dentistry as a "local")]]
|-
| bgcolor="#CCFF00" |02
| bgcolor="#66FF99" | [[it:Piperine|Piperine (active ingredient of both black and white pepper)]]
|-
| bgcolor="#CCFF00" |03
| bgcolor="#CCFF00" | [[it:Rapamycin|Rapamycin (prevents transplant rejection)]]
|-
| bgcolor="#CCFF00" |04
| bgcolor="#66FF99" | [[it:Gossypol|Gossypol (male birth control)]]
|-
| bgcolor="#CCFF00" |05
| bgcolor="#CCFF00" | [[it:Gentamycin|Gentamicin A (aminoglycoside antibiotic)]]
|-
| bgcolor="#CCFF00" |06
| bgcolor="#66FF99" | [[it:Herceptin|Herceptin (topical anticancer drug)]]
|-
| bgcolor="#CCFF00" |07
| bgcolor="#CCFF00" | [[it:Gingerone|Zingerone (the characteristic smell of ginger)]]
|-
| bgcolor="#CCFF00" |08
| bgcolor="#66FF99" | [[it:Sucralose|Sucralose (non-metabolizable sweetening agent)]]
|-
| bgcolor="#CCFF00" |09
| bgcolor="#CCFF00" | [[it:Bufotoxin|Bufotoxin (active component of the toad ''Bufo vulgaris'')]]
|-
| bgcolor="#CCFF00" |10
| bgcolor="#66FF99" | [[it:Roaccutane|Roaccutane (treatment for severe acne)]]
|-
| bgcolor="#CCFF00" |11
| bgcolor="#CCFF00" | [[it:Sibutramine|Sibutramine (appetite suppresor)]]
|-
| bgcolor="#CCFF00" |12
| bgcolor="#66FF99" | [[it:Anandamide|Anandamide (the "feel-good" factor in chocolate)]]
|-
| bgcolor="#CCFF00" |13
| bgcolor="#CCFF00" | [[it:h3nbh3|Ammonia-borane: H3N-BH3 (Hydrogen storage molecule?)]]
|-
| bgcolor="#CCFF00" |14
| bgcolor="#66FF99" | [[it:Methoxsalen|Methoxsalen (Treatment of psoriasis)]]
|-
| bgcolor="#CCFF00" |15
| bgcolor="#CCFF00" | [[it:Hycocine|Hyoscine (From Mandrake and Witches Henbane, pre-med before surgery)]]
|-
| bgcolor="#CCFF00" |16
| bgcolor="#66FF99" | [[it:Capreomycin|Capreomycin (Drug-resistant TB)]]
|-
| bgcolor="#CCFF00" |17
| bgcolor="#CCFF00" | [[it:wilkinson|Wilkinson's catalyst]]
|-
| bgcolor="#CCFF00" |18
| bgcolor="#66FF99" | [[it:Jacobsen|Jacobsen's epoxidation catalyst]]
|-
| bgcolor="#CCFF00" |19
| bgcolor="#CCFF00" | [[it:Methylaluminoxane|Methylaluminoxane: MAO - hugely important ethylene polymerisation cocatalyst]]
|-
| bgcolor="#CCFF00" |20
| bgcolor="#66FF99" | [[it:Schwartz|Schwartz reagent for the hydrozirconation of alkenes and alkynes]]
|}

== Supplemental Project Page ==

This area is for people who wish to create their own projects if none of the above appeal to them. Click on the '''Edit''' button to the right to open up an editable page,
then add an entry below as follows

*<nowiki> [[it:name_of_project|Descriptive name of intended project]]</nowiki>
*This will produce the effect: [[it:name_of_project|Descriptive name of intended project]]
----
*[[it:sitagliptin_page|Sitagliptin]]
*[[it:Retinal|Retinal, molecule of sight]]
*[[it:Tamoxifen|Tamoxifen, breast cancer treatment]]
*[[it:Morphine|Morphine, painkiller]]
*[[it:Pelargonidin|Pelargonidin, colouring in nature]]
*[[it:Propanil|Propanil, weedkiller]]
*[[it:Ranitidine|Ranitidine, antiulcerative]]
*[[it:chlorphentermine|chlorphentermine, anorectic]]
*[[it:Serotonin|Serotonin, The 'HAPPY' Drug]]
*[[it:Amphidinolide T1|Amphidinolide T1]]
*[[it:Rosiglitazone|Rosiglitazone, drug that is currently used to treat diabetes.]]
*[[it:Furosemide|Furosemide]]
*[[it:Tryptophan|Tryptophan]]
*[[it:methylpentynol|methylpentynol, tranquilliser.]]
*[[it:Ferrocene|Ferrocene]]
*[[it:Scopolamine|Scopolamine, the (Former) Truth Drug]]
*[[it:Camptothecin|Camptothecin,Anti-cancer agent ]]
*[[it:Salmeterol|Salmeterol, an agonist used to treat asthma]]
*[[it:Psilocin|Psilocin]]
*[[it:Epibatidine|Epibatidine]]
*[[it:Beta Carotene|Beta Carotene]]
*[[it:Thyroxine|Thyroxine, the Thyroid Hormone]]
*[[it:Tetrahydrocannabinol|Tetrahydrocannabinol]]
*[[it:Linalool|Linalool(A component of essential oil)]]
*[[it:Dihydroartemisinin| Dihydroartemisinin, An Active Anti-Malarial]]
*[[it:Acrolein|Acrolein]]
*[[it:Cinnamaldehyde|Cinnamaldehde: The smell and taste in the spice cinnamon]]
*[[it:Melatonin|Melatonin: The All-Natural Nightcap]]
*[[it:Benzylpiperazine|Benzylpiperazine (BZP): Party Pills]]
*[[it:Vanillin|Vanillin, flavouring used in food]]
*[[it:Gingerol|Gingerol, precursor of Zingerone]]
*[[it:MSG|MSG; because everyone loves the flavour]]
*[[it:DDT|DDT, Pesticide]]

== [[Special:Export|Export Pages]] ==

This takes you to an '''Export''' page. A backup of the Projects area can be made (in XML) if you want to keep your own ''snapshot'' of the project pages at any instant. After you Export the page you want (ie '''It:projects''' or '''It:Lignocaine''' for example) the XML encoding of it will appear in your browser Window. You should '''view source''' for this material, copy it to a text editor, and thence save it to disk.

== Overlaps ==

If someone else starts editing a page at the same time as you, the system will detect this and offer alternatives for you to deal with. For example, it may suggest you copy the contents of the page you have been editing and merge it into the other person's page,
so that both the sets of edits are preserved. Read the on-screen instructions carefully!

Another precaution you could take is to keep a copy of the contents of the page you are editing in eg Wordpad (or Word),
make the changes there, and then copy the entire lot to the Wiki page to preview and then save. That way, if your contribution
is overlapped by someone else, you will still have a copy, and you can then resubmit it.
----
--[[User:Rzepa|Rzepa]] 12:25, 19 October 2006 (BST)--[[User:Rzepa|Rzepa]] 08:31, 5 November 2006 (UTC)

== Wiki Utillities ==
Utilities have been written to help the conversion of material from HTML.

# [http://diberri.dyndns.org/wikipedia/html2wiki/ A HTML2Wiki Converter]

No wiki2html converter suitable for use has yet been identified.
=== Wiki Templates ===

[[Template:DOI]] and [[Template:Doi-inline]] are providea as (protected) templates for your use. Many other templates exist, often to be found on e.g. Wikipedia pages. You may decide one of these is of particular use, or of interest. If so, you can install it on the wiki here for you and others to use. Add below a line that looks like {{template-name|parameter}}, save, and click on the red text to create the new template. If you prefer the task of adding useful templates to that of adding information about molecules, then you will be given full credit for performing this valuable service for others!
--[[User:Rzepa|Rzepa]] 14:41, 20 October 2006 (BST)

----
[[Template:Chem-Data]]

[[Template:Chembox supplement]] - to be linked to from the supplementary section of the table in the template above, for usage see [[Template_talk:chembox_supplement|here]]

[[Template:NFPA_704]] - for notes on how to use, see [[Template_talk:NFPA_704|here]]

[[R & S Phrases]]

It:wilkinson

2006-10-31T12:15:54Z

Kfl05:

==Wilkinson's Catalyst==

Wilkinson's catalyst is ''Tris(triphenylphosphine) rhodium(I) chloride'' or ''chloro-tris(triphenylphosphine) rhodium(i)'' the structure of which is shown in the picture below:

[[Image:WCat.gif|thumb|A gif picture of Tris(triphenylphosphine) rhodium(I) chloride (Wilkinson's catalyst) from eMolecules.com]]

And here is a 3D picture:

<jmol>
<jmolApplet>
<size>400</size>
<color>white</color>
<script>zoom 100; ball and Stick on;frame 1; move 10 -20 10 0 0 0 0 0 3; delay 1;</script>
<inlineContents>wilkinsoncat.mol

104112 0 0 0 1 V2000
0.4884 -0.1610 -0.1106 Rh 0 0 0 0 0
1.1431 1.9689 -3.0329 C 0 0 0 0 0
0.5202 1.6759 -4.2514 C 0 0 0 0 0
0.0553 2.6804 -5.1025 C 0 0 0 0 0
0.2381 4.0214 -4.7685 C 0 0 0 0 0
0.8850 4.3392 -3.5753 C 0 0 0 0 0
1.3168 3.3241 -2.7189 C 0 0 0 0 0
3.2256 1.6612 -1.1825 C 0 0 0 0 0
4.2895 2.0906 -1.9837 C 0 0 0 0 0
5.3078 2.8854 -1.4532 C 0 0 0 0 0
5.2415 3.3147 -0.1271 C 0 0 0 0 0
4.1415 2.9626 0.6556 C 0 0 0 0 0
3.1433 2.1422 0.1273 C 0 0 0 0 0
2.5553 -0.6693 -2.9837 C 0 0 0 0 0
1.7496 -1.4378 -3.8325 C 0 0 0 0 0
2.2861 -2.4006 -4.6897 C 0 0 0 0 0
3.6580 -2.6491 -4.6887 C 0 0 0 0 0
4.4770 -1.9229 -3.8252 C 0 0 0 0 0
3.9271 -0.9472 -2.9908 C 0 0 0 0 0
1.8066 0.6402 -1.8755 P 0 3 0 0 0
2.4895 -3.0116 -0.7006 C 0 0 0 0 0
1.4692 -3.3726 -1.5868 C 0 0 0 0 0
1.6312 -4.4478 -2.4627 C 0 0 0 0 0
2.8163 -5.1844 -2.4521 C 0 0 0 0 0
3.8158 -4.8684 -1.5308 C 0 0 0 0 0
3.6375 -3.8077 -0.6402 C 0 0 0 0 0
1.6930 -2.8219 1.9100 C 0 0 0 0 0
2.4316 -2.9296 3.0942 C 0 0 0 0 0
2.0614 -3.8291 4.0967 C 0 0 0 0 0
0.9548 -4.6600 3.9209 C 0 0 0 0 0
0.2341 -4.5961 2.7283 C 0 0 0 0 0
0.6105 -3.6936 1.7315 C 0 0 0 0 0
3.7082 -0.8006 1.1206 C 0 0 0 0 0
4.9447 -0.9029 0.4774 C 0 0 0 0 0
6.0713 -0.2464 0.9766 C 0 0 0 0 0
5.9780 0.5179 2.1402 C 0 0 0 0 0
4.7485 0.6342 2.7897 C 0 0 0 0 0
3.6218 -0.0078 2.2721 C 0 0 0 0 0
2.1677 -1.6384 0.5153 P 0 3 0 0 0
-0.8050 -0.9240 1.5944 Cl 0 0 0 0 0
-1.2673 1.3055 -0.7138 P 0 3 0 0 0
-1.9600 0.9997 -2.4063 C 0 0 0 0 0
-2.8510 1.8725 -3.0379 C 0 0 0 0 0
-3.3692 1.5738 -4.2997 C 0 0 0 0 0
-3.0491 0.3654 -4.9203 C 0 0 0 0 0
-2.2384 -0.5554 -4.2555 C 0 0 0 0 0
-1.7160 -0.2435 -2.9988 C 0 0 0 0 0
-0.7810 3.0491 -0.3062 C 0 0 0 0 0
-0.1187 3.2408 0.9128 C 0 0 0 0 0
0.2956 4.5106 1.3177 C 0 0 0 0 0
0.0355 5.6176 0.5096 C 0 0 0 0 0
-0.6485 5.4438 -0.6940 C 0 0 0 0 0
-1.0576 4.1696 -1.0938 C 0 0 0 0 0
-2.8463 1.0234 0.2603 C 0 0 0 0 0
-3.5530 -0.1726 0.0865 C 0 0 0 0 0
-4.7370 -0.4120 0.7866 C 0 0 0 0 0
-5.2370 0.5519 1.6631 C 0 0 0 0 0
-4.5463 1.7523 1.8348 C 0 0 0 0 0
-3.3593 1.9856 1.1369 C 0 0 0 0 0
0.3800 0.6415 -4.5854 H 0 0 0 0 0
-0.4429 2.4148 -6.0491 H 0 0 0 0 0
-0.1140 4.8185 -5.4421 H 0 0 0 0 0
1.0451 5.3954 -3.3036 H 0 0 0 0 0
1.8069 3.6360 -1.7841 H 0 0 0 0 0
4.3314 1.8231 -3.0516 H 0 0 0 0 0
6.1490 3.2015 -2.0911 H 0 0 0 0 0
6.0335 3.9578 0.2887 H 0 0 0 0 0
4.0574 3.3374 1.6885 H 0 0 0 0 0
2.2746 1.8922 0.7534 H 0 0 0 0 0
0.6584 -1.3179 -3.8324 H 0 0 0 0 0
1.6220 -2.9883 -5.3441 H 0 0 0 0 0
4.0844 -3.4247 -5.3442 H 0 0 0 0 0
5.5606 -2.1234 -3.7998 H 0 0 0 0 0
4.6167 -0.4073 -2.3293 H 0 0 0 0 0
0.5148 -2.8211 -1.5913 H 0 0 0 0 0
0.8200 -4.7186 -3.1578 H 0 0 0 0 0
2.9459 -6.0336 -3.1421 H 0 0 0 0 0
4.7305 -5.4811 -1.4819 H 0 0 0 0 0
4.4065 -3.6300 0.1274 H 0 0 0 0 0
3.3326 -2.3235 3.2645 H 0 0 0 0 0
2.6540 -3.8952 5.0239 H 0 0 0 0 0
0.6662 -5.3756 4.7074 H 0 0 0 0 0
-0.6272 -5.2652 2.5700 H 0 0 0 0 0
0.0300 -3.6842 0.7953 H 0 0 0 0 0
5.0569 -1.5000 -0.4374 H 0 0 0 0 0
7.0365 -0.3324 0.4516 H 0 0 0 0 0
6.8657 1.0364 2.5360 H 0 0 0 0 0
4.6632 1.2478 3.7011 H 0 0 0 0 0
2.6569 0.1188 2.7908 H 0 0 0 0 0
-3.1849 2.7955 -2.5425 H 0 0 0 0 0
-4.0593 2.2779 -4.7924 H 0 0 0 0 0
-3.4716 0.1205 -5.9078 H 0 0 0 0 0
-2.0239 -1.5340 -4.7144 H 0 0 0 0 0
-1.1149 -0.9986 -2.4682 H 0 0 0 0 0
0.0849 2.3852 1.5776 H 0 0 0 0 0
0.8246 4.6387 2.2757 H 0 0 0 0 0
0.3629 6.6219 0.8221 H 0 0 0 0 0
-0.8555 6.3149 -1.3365 H 0 0 0 0 0
-1.5785 4.0746 -2.0551 H 0 0 0 0 0
-3.1824 -0.9476 -0.6037 H 0 0 0 0 0
-5.2797 -1.3605 0.6443 H 0 0 0 0 0
-6.1750 0.3688 2.2115 H 0 0 0 0 0
-4.9429 2.5200 2.5189 H 0 0 0 0 0
-2.8474 2.9476 1.2892 H 0 0 0 0 0
1 20 1 6 0 0
1 39 1 0 0 0
1 40 1 1 0 0
1 41 1 0 0 0
2 3 2 0 0 0
2 7 1 0 0 0
2 20 1 1 0 0
3 4 1 6 0 0
3 60 1 0 0 0
4 5 2 0 0 0
4 61 1 6 0 0
5 6 1 1 0 0
5 62 1 6 0 0
6 7 2 0 0 0
6 63 1 0 0 0
7 64 1 1 0 0
8 9 2 0 0 0
8 13 1 1 0 0
8 20 1 0 0 0
9 10 1 0 0 0
9 65 1 6 0 0
10 11 2 0 0 0
10 66 1 6 0 0
11 12 1 1 0 0
11 67 1 0 0 0
12 13 2 0 0 0
12 68 1 1 0 0
13 69 1 1 0 0
14 15 2 0 0 0
14 19 1 0 0 0
14 20 1 1 0 0
15 16 1 6 0 0
15 70 1 0 0 0
16 17 2 0 0 0
16 71 1 6 0 0
17 18 1 1 0 0
17 72 1 6 0 0
18 19 2 0 0 0
18 73 1 0 0 0
19 74 1 1 0 0
21 22 2 0 0 0
21 26 1 0 0 0
21 39 1 1 0 0
22 23 1 6 0 0
22 75 1 0 0 0
23 24 2 0 0 0
23 76 1 6 0 0
24 25 1 1 0 0
24 77 1 6 0 0
25 26 2 0 0 0
25 78 1 0 0 0
26 79 1 1 0 0
27 28 2 0 0 0
27 32 1 0 0 0
27 39 1 6 0 0
28 29 1 1 0 0
28 80 1 0 0 0
29 30 2 0 0 0
29 81 1 1 0 0
30 31 1 6 0 0
30 82 1 1 0 0
31 32 2 0 0 0
31 83 1 0 0 0
32 84 1 6 0 0
33 34 2 0 0 0
33 38 1 1 0 0
33 39 1 0 0 0
34 35 1 0 0 0
34 85 1 6 0 0
35 36 2 0 0 0
35 86 1 6 0 0
36 37 1 1 0 0
36 87 1 0 0 0
37 38 2 0 0 0
37 88 1 1 0 0
38 89 1 1 0 0
41 42 1 6 0 0
41 48 1 0 0 0
41 54 1 1 0 0
42 43 2 0 0 0
42 47 1 0 0 0
43 44 1 6 0 0
43 90 1 1 0 0
44 45 2 0 0 0
44 91 1 0 0 0
45 46 1 1 0 0
45 92 1 6 0 0
46 47 2 0 0 0
46 93 1 0 0 0
47 94 1 1 0 0
48 49 2 0 0 0
48 53 1 6 0 0
49 50 1 0 0 0
49 95 1 1 0 0
50 51 2 0 0 0
50 96 1 1 0 0
51 52 1 6 0 0
51 97 1 0 0 0
52 53 2 0 0 0
52 98 1 6 0 0
53 99 1 6 0 0
54 55 2 0 0 0
54 59 1 1 0 0
55 56 1 1 0 0
55100 1 6 0 0
56 57 2 0 0 0
56101 1 0 0 0
57 58 1 0 0 0
57102 1 1 0 0
58 59 2 0 0 0
58103 1 1 0 0
59104 1 0 0 0
M END</inlineContents>
</jmolApplet>
</jmol>

The formula for Wilkinsons Catalyst is C54H45ClP3Rh

==An example of the Wilkinson Catalyst reaction:==
The Wilkinson catalyst RhCl(PPh3)3 is known to react with pyridine to lead to the 'reductive coupling of aldehydes'2. The pyridine molecule is able to react well with the catalyst since it is able to exchange its ligands with the catalyst, for example [RhCl(py)(PPh3)2]. When the pyridine reacts with the catalyst, a solution forms and chemists are then able to study the selectivity of the catalyst as to maximise its role as a catalyst.

2.J. Chem. Soc., Dalton Trans., 1994, 2875 - 2880, DOI: 10.1039/DT9940002875

==Structure and Synthesis==

This compound RhCl(PPh3) is a ''square planar'', 16-electron complex, and is usually isolated in the form of a red-violet crystalline solid from the reaction of ''rhodium trichloride'' with ''triphenylphosphine''. The synthesis is conducted in refluxing ethanol.

RhCl3(H2O)3 + CH3CH2OH + 3 PPh3 -> RhCl(PPh3)3 + CH3CHO + 2 HCl + 3 H2O

[[Image:Wilkinson_Catalyst.GIF|thumb|A gif picture of Tris(triphenylphosphine) rhodium(I) chloride (Wilkinson's catalyst) from eMolecules.com]]

In hydrogenation of an alken: Before activation, RhCl(PPh3)3 is a ''square planar'' complex in which rhodium is in oxidation state 1. Then it loses one of the phenylphosine group. Dihydrogen, H2, is then homolytically dissociates into two hydrogen atoms which each coordinate to the rhodium oxidative addition: the metal's oxidation number increases to 3. The resulting ''octahedral'' complex then loses one of its phosphine ligands, which is replaced by the alkene.

One of the hydrogen atoms then transfers from the rhodium to the alkene, which becomes an alkyl ligand. The expelled phosphine ligand resumes its place in the complex and the remaining hydrogen then also transfers to the alkyl ligand, which becomes an alkane and leaves the complex. Thus the original Wilkinson complex, with all three phosphine ligands, is restored.

The link below contain an animation which show how the H2 and the alkene attach to the metal centre. [[http://www.ncl.ox.ac.uk/quicktime/hydrogenation.html]]

==A brief history of the Wilkinson catalyst:==
The catalyst is named after Profesor Sir Geoffrey Wilkinson who won a Nobel Laureate for chemistry. The structure as you can see above is organometallic and 'activates' small molecules therefore the catalyst lowers the activation energies for bond making and bond breaking. Profesor Wilkinson himself was involved heavily in the inorganic field and pioneered the organometallic chemistry age.

http://www.3dchem.com/molecules.asp?ID=35#

<jmol>
<jmolApplet>
<size>500</size>
<color>white</color>
<script>zoom 100; cpk off;frame 1; move 10 -20 10 0 0 0 0 0 3; delay 1;</script>
<inlineContents>HEADER CSD ENTRY TPPRHC01
COMPND UNNAMED
AUTHOR GENERATED BY CONQUEST
CRYST1 19.470 12.689 18.202 90.00 90.00 90.00 P n a 21 4
ATOM 1 Rh1 UNK 0 1 1.227 0.367 4.551 1.00 0.00
ATOM 2 Cl1 UNK 0 1 -0.989 0.921 3.801 1.00 0.00
ATOM 3 P1 UNK 0 1 1.558 2.646 4.651 1.00 0.00
ATOM 4 P2 UNK 0 1 3.355 -0.253 4.745 1.00 0.00
ATOM 5 P3 UNK 0 1 0.300 -1.728 5.018 1.00 0.00
ATOM 6 C1 UNK 0 1 0.481 3.464 5.897 1.00 0.00
ATOM 7 C2 UNK 0 1 0.724 4.784 6.260 1.00 0.00
ATOM 8 C3 UNK 0 1 -0.105 5.416 7.181 1.00 0.00
ATOM 9 C4 UNK 0 1 -1.178 4.733 7.741 1.00 0.00
ATOM 10 C5 UNK 0 1 -1.421 3.401 7.379 1.00 0.00
ATOM 11 C6 UNK 0 1 -0.594 2.771 6.458 1.00 0.00
ATOM 12 C7 UNK 0 1 1.180 3.528 3.093 1.00 0.00
ATOM 13 C8 UNK 0 1 1.279 2.774 1.928 1.00 0.00
ATOM 14 C9 UNK 0 1 1.069 3.375 0.690 1.00 0.00
ATOM 15 C10 UNK 0 1 0.757 4.733 0.617 1.00 0.00
ATOM 16 C11 UNK 0 1 0.658 5.484 1.782 1.00 0.00
ATOM 17 C12 UNK 0 1 0.868 4.885 3.020 1.00 0.00
ATOM 18 C13 UNK 0 1 3.154 3.416 5.129 1.00 0.00
ATOM 19 C14 UNK 0 1 3.913 4.126 4.201 1.00 0.00
ATOM 20 C15 UNK 0 1 5.089 4.753 4.605 1.00 0.00
ATOM 21 C16 UNK 0 1 5.510 4.670 5.923 1.00 0.00
ATOM 22 C17 UNK 0 1 4.751 3.958 6.849 1.00 0.00
ATOM 23 C18 UNK 0 1 3.577 3.331 6.462 1.00 0.00
ATOM 24 C19 UNK 0 1 4.665 0.803 4.004 1.00 0.00
ATOM 25 C20 UNK 0 1 4.517 1.081 2.641 1.00 0.00
ATOM 26 C21 UNK 0 1 5.491 1.807 1.968 1.00 0.00
ATOM 27 C22 UNK 0 1 6.622 2.255 2.657 1.00 0.00
ATOM 28 C23 UNK 0 1 6.776 1.978 4.006 1.00 0.00
ATOM 29 C24 UNK 0 1 5.802 1.252 4.680 1.00 0.00
ATOM 30 C25 UNK 0 1 3.670 -1.769 3.726 1.00 0.00
ATOM 31 C26 UNK 0 1 2.884 -1.902 2.585 1.00 0.00
ATOM 32 C27 UNK 0 1 3.102 -2.957 1.709 1.00 0.00
ATOM 33 C28 UNK 0 1 4.106 -3.888 1.975 1.00 0.00
ATOM 34 C29 UNK 0 1 4.893 -3.755 3.116 1.00 0.00
ATOM 35 C30 UNK 0 1 4.675 -2.690 3.992 1.00 0.00
ATOM 36 C31 UNK 0 1 3.972 -0.558 6.480 1.00 0.00
ATOM 37 C32 UNK 0 1 5.218 -1.104 6.771 1.00 0.00
ATOM 38 C33 UNK 0 1 5.605 -1.320 8.100 1.00 0.00
ATOM 39 C34 UNK 0 1 4.751 -0.964 9.137 1.00 0.00
ATOM 40 C35 UNK 0 1 3.505 -0.406 8.846 1.00 0.00
ATOM 41 C36 UNK 0 1 3.117 -0.203 7.517 1.00 0.00
ATOM 42 C37 UNK 0 1 -1.038 -1.377 6.254 1.00 0.00
ATOM 43 C38 UNK 0 1 -0.738 -0.510 7.303 1.00 0.00
ATOM 44 C39 UNK 0 1 -1.706 -0.212 8.258 1.00 0.00
ATOM 45 C40 UNK 0 1 -2.973 -0.778 8.165 1.00 0.00
ATOM 46 C41 UNK 0 1 -3.275 -1.643 7.119 1.00 0.00
ATOM 47 C42 UNK 0 1 -2.307 -1.943 6.161 1.00 0.00
ATOM 48 C43 UNK 0 1 1.264 -3.073 5.839 1.00 0.00
ATOM 49 C44 UNK 0 1 1.879 -4.060 5.069 1.00 0.00
ATOM 50 C45 UNK 0 1 2.658 -5.035 5.681 1.00 0.00
ATOM 51 C46 UNK 0 1 2.821 -5.031 7.062 1.00 0.00
ATOM 52 C47 UNK 0 1 2.206 -4.048 7.834 1.00 0.00
ATOM 53 C48 UNK 0 1 1.427 -3.069 7.223 1.00 0.00
ATOM 54 C49 UNK 0 1 -0.541 -2.690 3.708 1.00 0.00
ATOM 55 C50 UNK 0 1 -0.641 -2.122 2.439 1.00 0.00
ATOM 56 C51 UNK 0 1 -1.266 -2.817 1.411 1.00 0.00
ATOM 57 C52 UNK 0 1 -1.793 -4.086 1.649 1.00 0.00
ATOM 58 C53 UNK 0 1 -1.694 -4.656 2.918 1.00 0.00
ATOM 59 C54 UNK 0 1 -1.069 -3.959 3.946 1.00 0.00
ATOM 60 H1 UNK 0 1 1.499 5.279 5.861 1.00 0.00
ATOM 61 H2 UNK 0 1 0.078 6.357 7.463 1.00 0.00
ATOM 62 H3 UNK 0 1 -1.772 5.177 8.409 1.00 0.00
ATOM 63 H4 UNK 0 1 -2.181 2.906 7.772 1.00 0.00
ATOM 64 H5 UNK 0 1 -0.759 1.827 6.189 1.00 0.00
ATOM 65 H6 UNK 0 1 1.499 1.802 1.984 1.00 0.00
ATOM 66 H7 UNK 0 1 1.149 2.830 -0.146 1.00 0.00
ATOM 67 H8 UNK 0 1 0.604 5.164 -0.273 1.00 0.00
ATOM 68 H9 UNK 0 1 0.428 6.459 1.729 1.00 0.00
ATOM 69 H10 UNK 0 1 0.798 5.418 3.859 1.00 0.00
ATOM 70 H11 UNK 0 1 3.621 4.200 3.258 1.00 0.00
ATOM 71 H12 UNK 0 1 5.646 5.279 3.968 1.00 0.00
ATOM 72 H13 UNK 0 1 6.347 5.114 6.243 1.00 0.00
ATOM 73 H14 UNK 0 1 5.043 3.870 7.809 1.00 0.00
ATOM 74 H15 UNK 0 1 3.018 2.804 7.117 1.00 0.00
ATOM 75 H16 UNK 0 1 3.699 0.761 2.148 1.00 0.00
ATOM 76 H17 UNK 0 1 5.393 2.005 0.983 1.00 0.00
ATOM 77 H18 UNK 0 1 7.321 2.779 2.166 1.00 0.00
ATOM 78 H19 UNK 0 1 7.593 2.297 4.496 1.00 0.00
ATOM 79 H20 UNK 0 1 5.899 1.053 5.643 1.00 0.00
ATOM 80 H21 UNK 0 1 2.161 -1.231 2.403 1.00 0.00
ATOM 81 H22 UNK 0 1 2.531 -3.058 0.892 1.00 0.00
ATOM 82 H23 UNK 0 1 4.264 -4.644 1.347 1.00 0.00
ATOM 83 H24 UNK 0 1 5.607 -4.428 3.295 1.00 0.00
ATOM 84 H25 UNK 0 1 5.237 -2.601 4.805 1.00 0.00
ATOM 85 H26 UNK 0 1 5.841 -1.358 6.025 1.00 0.00
ATOM 86 H27 UNK 0 1 6.503 -1.713 8.318 1.00 0.00
ATOM 87 H28 UNK 0 1 5.004 -1.104 10.084 1.00 0.00
ATOM 88 H29 UNK 0 1 2.882 -0.152 9.592 1.00 0.00
ATOM 89 H30 UNK 0 1 2.220 0.190 7.317 1.00 0.00
ATOM 90 H31 UNK 0 1 0.175 -0.102 7.372 1.00 0.00
ATOM 91 H32 UNK 0 1 -1.499 0.406 9.010 1.00 0.00
ATOM 92 H33 UNK 0 1 -3.660 -0.571 8.846 1.00 0.00
ATOM 93 H34 UNK 0 1 -4.186 -2.056 7.044 1.00 0.00
ATOM 94 H35 UNK 0 1 -2.531 -2.563 5.406 1.00 0.00
ATOM 95 H36 UNK 0 1 1.772 -4.073 4.077 1.00 0.00
ATOM 96 H37 UNK 0 1 3.115 -5.748 5.151 1.00 0.00
ATOM 97 H38 UNK 0 1 3.368 -5.723 7.536 1.00 0.00
ATOM 98 H39 UNK 0 1 2.317 -4.035 8.846 1.00 0.00
ATOM 99 H40 UNK 0 1 0.974 -2.360 7.772 1.00 0.00
ATOM 100 H41 UNK 0 1 -0.253 -1.218 2.257 1.00 0.00
ATOM 101 H42 UNK 0 1 -1.343 -2.424 0.491 1.00 0.00
ATOM 102 H43 UNK 0 1 -2.239 -4.606 0.910 1.00 0.00
ATOM 103 H44 UNK 0 1 -2.083 -5.570 3.094 1.00 0.00
ATOM 104 H45 UNK 0 1 -0.993 -4.352 4.860 1.00 0.00
CONECT 1 2 3 4 5
CONECT 2 1
CONECT 3 1 6 12 18
CONECT 4 1 24 30 36
CONECT 5 1 42 48 54
CONECT 6 3 7 11
CONECT 7 6 8 60
CONECT 8 7 9 61
CONECT 9 8 10 62
CONECT 10 9 11 63
CONECT 11 6 10 64
CONECT 12 3 13 17
CONECT 13 12 14 65
CONECT 14 13 15 66
CONECT 15 14 16 67
CONECT 16 15 17 68
CONECT 17 12 16 69
CONECT 18 3 19 23
CONECT 19 18 20 70
CONECT 20 19 21 71
CONECT 21 20 22 72
CONECT 22 21 23 73
CONECT 23 18 22 74
CONECT 24 4 25 29
CONECT 25 24 26 75
CONECT 26 25 27 76
CONECT 27 26 28 77
CONECT 28 27 29 78
CONECT 29 24 28 79
CONECT 30 4 31 35
CONECT 31 30 32 80
CONECT 32 31 33 81
CONECT 33 32 34 82
CONECT 34 33 35 83
CONECT 35 30 34 84
CONECT 36 4 37 41
CONECT 37 36 38 85
CONECT 38 37 39 86
CONECT 39 38 40 87
CONECT 40 39 41 88
CONECT 41 36 40 89
CONECT 42 5 43 47
CONECT 43 42 44 90
CONECT 44 43 45 91
CONECT 45 44 46 92
CONECT 46 45 47 93
CONECT 47 42 46 94
CONECT 48 5 49 53
CONECT 49 48 50 95
CONECT 50 49 51 96
CONECT 51 50 52 97
CONECT 52 51 53 98
CONECT 53 48 52 99
CONECT 54 5 55 59
CONECT 55 54 56 100
CONECT 56 55 57 101
CONECT 57 56 58 102
CONECT 58 57 59 103
CONECT 59 54 58 104
CONECT 60 7
CONECT 61 8
CONECT 62 9
CONECT 63 10
CONECT 64 11
CONECT 65 13
CONECT 66 14
CONECT 67 15
CONECT 68 16
CONECT 69 17
CONECT 70 19
CONECT 71 20
CONECT 72 21
CONECT 73 22
CONECT 74 23
CONECT 75 25
CONECT 76 26
CONECT 77 27
CONECT 78 28
CONECT 79 29
CONECT 80 31
CONECT 81 32
CONECT 82 33
CONECT 83 34
CONECT 84 35
CONECT 85 37
CONECT 86 38
CONECT 87 39
CONECT 88 40
CONECT 89 41
CONECT 90 43
CONECT 91 44
CONECT 92 45
CONECT 93 46
CONECT 94 47
CONECT 95 49
CONECT 96 50
CONECT 97 51
CONECT 98 52
CONECT 99 53
CONECT 100 55
CONECT 101 56
CONECT 102 57
CONECT 103 58
CONECT 104 59
MASTER 0 0 0 0 0 0 0 0 104 0 104 0
END</inlineContents>
</jmolApplet>
</jmol>

The above 3D picture was firstly drawn in the ConQuest programme using 2D tools and then a search for the 3D molecule was made giving the following hit as you see.

==Comparison with other catalysts:==
Two other famous catalysts used in many chemical reactions are Ni and Pd and these comoplexes can be better or worse than the Wilkinson catalyst in some properties. For example, the Wilkinson catalyst is more active and so faster reactions are possible. This is shown by comparing therate constants in the table below as the magnitude of k is largest for the Wilkinson catalyst. Another advantage of this catalyst is that in comparison with the reactant and product phases, the catalyst can either be homogeneous or heterogeneous, whilst the other 2 catalyst are normally in the solid phase.

[[Image:cattable.gif|thumb|centre|200|Comparison of the Wilkinson catalyst with Pd and Ni]]

With THT present (above in the table), the Rh complex will change its coordination by a larger amount but the Pd and Ni catalyst retain its original coordination number. Once again, this is better as a catalyst as the larger surface in the larger coordination sphere is able to act as an bigger active site for the reactants to attach to. Finally, the Rh catalyst shows a great resistance to sulphur poisoning with organic compounds containing S atoms but Pd and Ni do not. The Wilkinson catalyst works well when it is complexed to a γ-Al2O3 surface to catalyse the hydrogenation reaction of olefins.

Ref:
Journal of Molecular Catalysis A: Chemical
Volume 149, Issues 1-2 , 15 December 1999, Pages 147-152
or http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TGM-3Y9RF5P-J&_coverDate=12%2F15%2F1999&_alid=475460761&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=5258&_sort=d&view=c&_acct=C000011279&_version=1&_urlVersion=0&_userid=217827&md5=16c34de59089a2a3e11dc01745af7d7d

==Olefin hydrogenation with the Wilkinson catalyst==
Adding to the above reaction scheme done by a collegeaue, the catalyst will react the olefin in the following ways to give transition stages on the way to the product.

[[Image:Stereochemwilk.GIF|thumb|centre|200|Description of image]]

The diagram shows the bond angles and bond lengths in angstroms. The angle of attack from the differing molecules is also shown according to experimental data.

Ref: J. Am. Chem. SOC. 1987, 109, 3455-3456

==References and External Links==

1. [http://www.sciencedirect.com/science/article/B6THD-4KWK10C-1/2/23598dfb1e674011a2e6aaef2ff7a4fe R. Acosta Ortiz, M. Sangermano, R. Bongiovanni, A. E. Garcia Valdez, L. B. Duarte, I. P. Saucedo and A. Priola, ''Progress in Organic Coatings'', 2006, '''57''', 159-164.]

==Properties==
{| class="toccolours" border="1" style="float: right; clear: right; margin: 0 0 1em 1em; border-collapse: collapse;"
! {{chembox header}}| '''Wilkinson's catalyst'''
|-
| align="center" colspan="2" bgcolor="#ffffff" | [[Image:Wilkinson's_catalyst1.png]]
|-
| [[IUPAC nomenclature|Chemical name]]
| ''Chlorotris(triphenylphosphine)- rhodium''
|-
| [[CAS nummber]]
| 14694-95-2
|-
| [[Chemical formula]]
| {{{formula|C54H45ClP3Rh
|-
| [[Molecular mass]]
| {{{mol_mass|925.22 g/mol
|-
| [[Solubility in water]]
| {{{Solubility in water|Insoluble
|-
| [[Melting point]]
| {{{Melting point|245-250 °C
|-
| [[Appearance]]
| {{{Appearance| red solid
|-
| [[Coordination geometry]]
| {{{Coordination geometry| square planar
|}

File:Wilkinson's catalyst1.png

2006-10-31T12:10:30Z

Kfl05:

It:Jacobsen

2006-10-26T11:36:23Z

Kfl05: /* '''Jacobsen Catalyst''' */

=='''Jacobsen Catalyst'''==
==='''Introduction'''===
Jacobsen catalyst is the most efficient and commercially available compound among the chiral manganese(III)-salen complexes with the IUPAC name: ''N,N'-Bis(3,5-di-tert-butylsalicylidene)-1,2-diaminocyclohexylmanganese(III) chloride''. As the name suggests, the compound is widely used as a catalyst in the epoxidation of olefins for its enantioseletivity.

{| class="toccolours" border="1" style="float: right; clear: right; margin: 0 0 1em 1em; border-collapse: collapse;"
! {{chembox header}}| '''Jacobsen Catalyst'''
|-
| align="center" colspan="2" bgcolor="#ffffff" | [[Image:Jacobsen_catalyst.gif]]
|-
| [[IUPAC nomenclature|Chemical name]]
| ''N,N'-Bis(3,5-di-tert-butylsalicylidene)-1,2-diaminocyclohexylmanganese(III) chloride''
|-
| [[CAS nummber]]
| 138124-32-0
|-
| [[Chemical formula]]
| {{{formula|C36H52ClMnN2O2
|-
| [[Molecular mass]]
| {{{mol_mass|635.21 g/mol
|-
| [[Simplified molecular input line entry specification|SMILES]]
| {{{SMILES|[Me3C]C(C=C2C(C)(C)C)=CC1=C2O[Mn+3]45[N]([C@H]3[C@H]
([N]4=CC(C=C(C(C)(C)C)C=C6[Me3C])=C6O5)CCCC3)=C1
|-
| [[Colour]]
| {{{Colour| Brown
|-
|}

<jmol>
<jmolApplet>
<size>300</size>
<color>white</color>
<script>zoom 100; cpk off;frame 3; move 10 -20 10 0 0 0 0 0 3; delay 1;</script>
<inlineContents>HEADER NONAME 19-Oct-06 NONE 1
TITLE NONE 2
AUTHOR WWW daemon apache NONE 3
REVDAT 1 19-Oct-06 0 NONE 4
ATOM 1 C 0 -5.987 -2.724 0.763 0.00 0.00 C+0
ATOM 2 C 0 -5.157 -2.243 -0.430 0.00 0.00 C+0
ATOM 3 C 0 -3.953 -1.487 0.069 0.00 0.00 C+0
ATOM 4 C 0 -3.029 -2.117 0.886 0.00 0.00 C+0
ATOM 5 C 0 -1.915 -1.431 1.316 0.00 0.00 C+0
ATOM 6 C 0 -0.915 -2.125 2.205 0.00 0.00 C+0
ATOM 7 C 0 -1.395 -3.547 2.500 0.00 0.00 C+0
ATOM 8 C 0 0.442 -2.181 1.499 0.00 0.00 C+0
ATOM 9 C 0 -0.776 -1.350 3.517 0.00 0.00 C+0
ATOM 10 C 0 -3.768 -0.176 -0.292 0.00 0.00 C+0
ATOM 11 C 0 -2.649 0.553 0.160 0.00 0.00 C+0
ATOM 12 C 0 -1.697 -0.105 0.941 0.00 0.00 C+0
ATOM 13 O 0 -0.457 0.388 1.349 0.00 0.00 O+0
ATOM 14 Mn 0 -0.037 1.374 -0.073 0.00 0.00 Mn+3
ATOM 15 N 0 -1.515 2.546 -0.267 0.00 0.00 N+0
ATOM 16 C 0 -0.898 3.821 -0.006 0.00 0.00 C+0
ATOM 17 H 0 -1.110 4.047 1.039 0.00 0.00 H+0
ATOM 18 C 0 0.645 3.896 -0.139 0.00 0.00 C+0
ATOM 19 H 0 0.866 4.224 -1.154 0.00 0.00 H+0
ATOM 20 N 0 1.363 2.659 0.121 0.00 0.00 N+0
ATOM 21 C 0 2.516 2.124 0.253 0.00 0.00 C+0
ATOM 22 C 0 2.606 0.693 -0.168 0.00 0.00 C+0
ATOM 23 C 0 3.768 0.042 0.299 0.00 0.00 C+0
ATOM 24 C 0 4.040 -1.260 -0.032 0.00 0.00 C+0
ATOM 25 C 0 5.286 -1.927 0.491 0.00 0.00 C+0
ATOM 26 C 0 6.066 -0.938 1.360 0.00 0.00 C+0
ATOM 27 C 0 4.898 -3.147 1.329 0.00 0.00 C+0
ATOM 28 C 0 6.159 -2.372 -0.684 0.00 0.00 C+0
ATOM 29 C 0 3.169 -1.964 -0.848 0.00 0.00 C+0
ATOM 30 C 0 2.020 -1.356 -1.300 0.00 0.00 C+0
ATOM 31 C 0 1.077 -2.126 -2.189 0.00 0.00 C+0
ATOM 32 C 0 1.620 -3.540 -2.405 0.00 0.00 C+0
ATOM 33 C 0 -0.300 -2.204 -1.527 0.00 0.00 C+0
ATOM 34 C 0 0.955 -1.415 -3.539 0.00 0.00 C+0
ATOM 35 C 0 1.711 -0.042 -0.950 0.00 0.00 C+0
ATOM 36 O 0 0.480 0.395 -1.461 0.00 0.00 O+0
ATOM 37 C 0 1.058 5.040 0.808 0.00 0.00 C+0
ATOM 38 C 0 0.492 6.328 0.192 0.00 0.00 C+0
ATOM 39 C 0 -1.021 6.266 0.017 0.00 0.00 C+0
ATOM 40 C 0 -1.434 5.015 -0.798 0.00 0.00 C+0
ATOM 41 C 0 -2.677 2.003 -0.219 0.00 0.00 C+0
ATOM 42 C 0 -4.698 -3.449 -1.252 0.00 0.00 C+0
ATOM 43 C 0 -6.010 -1.323 -1.306 0.00 0.00 C+0
ATOM 44 H 0 -6.313 -1.865 1.348 0.00 0.00 H+0
ATOM 45 H 0 -6.858 -3.271 0.402 0.00 0.00 H+0
ATOM 46 H 0 -5.379 -3.379 1.387 0.00 0.00 H+0
ATOM 47 H 0 -3.182 -3.143 1.186 0.00 0.00 H+0
ATOM 48 H 0 -1.494 -4.099 1.565 0.00 0.00 H+0
ATOM 49 H 0 -0.672 -4.049 3.143 0.00 0.00 H+0
ATOM 50 H 0 -2.361 -3.507 3.003 0.00 0.00 H+0
ATOM 51 H 0 0.709 -1.185 1.146 0.00 0.00 H+0
ATOM 52 H 0 1.200 -2.534 2.198 0.00 0.00 H+0
ATOM 53 H 0 0.382 -2.863 0.651 0.00 0.00 H+0
ATOM 54 H 0 -1.742 -1.311 4.019 0.00 0.00 H+0
ATOM 55 H 0 -0.052 -1.852 4.160 0.00 0.00 H+0
ATOM 56 H 0 -0.433 -0.337 3.306 0.00 0.00 H+0
ATOM 57 H 0 -4.491 0.306 -0.932 0.00 0.00 H+0
ATOM 58 H 0 3.365 2.667 0.640 0.00 0.00 H+0
ATOM 59 H 0 4.458 0.582 0.931 0.00 0.00 H+0
ATOM 60 H 0 5.445 -0.621 2.198 0.00 0.00 H+0
ATOM 61 H 0 6.968 -1.420 1.739 0.00 0.00 H+0
ATOM 62 H 0 6.343 -0.069 0.764 0.00 0.00 H+0
ATOM 63 H 0 4.343 -3.851 0.710 0.00 0.00 H+0
ATOM 64 H 0 5.800 -3.629 1.708 0.00 0.00 H+0
ATOM 65 H 0 4.277 -2.830 2.167 0.00 0.00 H+0
ATOM 66 H 0 6.435 -1.502 -1.281 0.00 0.00 H+0
ATOM 67 H 0 7.060 -2.854 -0.305 0.00 0.00 H+0
ATOM 68 H 0 5.603 -3.076 -1.303 0.00 0.00 H+0
ATOM 69 H 0 3.390 -2.983 -1.128 0.00 0.00 H+0
ATOM 70 H 0 1.708 -4.046 -1.444 0.00 0.00 H+0
ATOM 71 H 0 0.938 -4.096 -3.049 0.00 0.00 H+0
ATOM 72 H 0 2.601 -3.484 -2.877 0.00 0.00 H+0
ATOM 73 H 0 -0.558 -1.230 -1.111 0.00 0.00 H+0
ATOM 74 H 0 -1.044 -2.491 -2.269 0.00 0.00 H+0
ATOM 75 H 0 -0.277 -2.946 -0.729 0.00 0.00 H+0
ATOM 76 H 0 1.936 -1.359 -4.011 0.00 0.00 H+0
ATOM 77 H 0 0.273 -1.971 -4.182 0.00 0.00 H+0
ATOM 78 H 0 0.568 -0.407 -3.385 0.00 0.00 H+0
ATOM 79 H 0 0.632 4.879 1.799 0.00 0.00 H+0
ATOM 80 H 0 2.145 5.100 0.871 0.00 0.00 H+0
ATOM 81 H 0 0.739 7.169 0.840 0.00 0.00 H+0
ATOM 82 H 0 0.954 6.487 -0.782 0.00 0.00 H+0
ATOM 83 H 0 -1.492 6.240 1.000 0.00 0.00 H+0
ATOM 84 H 0 -1.355 7.159 -0.512 0.00 0.00 H+0
ATOM 85 H 0 -1.003 5.059 -1.798 0.00 0.00 H+0
ATOM 86 H 0 -2.521 4.948 -0.858 0.00 0.00 H+0
ATOM 87 H 0 -3.589 2.540 -0.431 0.00 0.00 H+0
ATOM 88 H 0 -5.570 -3.995 -1.612 0.00 0.00 H+0
ATOM 89 H 0 -4.107 -3.106 -2.101 0.00 0.00 H+0
ATOM 90 H 0 -4.091 -4.104 -0.628 0.00 0.00 H+0
ATOM 91 H 0 -6.337 -0.464 -0.720 0.00 0.00 H+0
ATOM 92 H 0 -5.419 -0.980 -2.155 0.00 0.00 H+0
ATOM 93 H 0 -6.881 -1.869 -1.666 0.00 0.00 H+0
CONECT 1 2 44 45 46 NONE 98
CONECT 2 1 3 42 43 NONE 99
CONECT 3 2 4 10 0 NONE 100
CONECT 4 3 5 47 0 NONE 101
CONECT 5 4 12 6 0 NONE 102
CONECT 6 5 7 8 9 NONE 103
CONECT 7 6 48 49 50 NONE 104
CONECT 8 6 51 52 53 NONE 105
CONECT 9 6 54 55 56 NONE 106
CONECT 10 3 11 57 0 NONE 107
CONECT 11 10 41 12 0 NONE 108
CONECT 12 11 5 13 0 NONE 109
CONECT 13 12 14 0 0 NONE 110
CONECT 14 13 20 36 15 NONE 111
CONECT 15 14 16 41 0 NONE 112
CONECT 16 15 17 40 18 NONE 113
CONECT 18 16 19 20 37 NONE 114
CONECT 20 18 14 21 0 NONE 115
CONECT 21 20 22 58 0 NONE 116
CONECT 22 21 23 35 0 NONE 117
CONECT 23 22 24 59 0 NONE 118
CONECT 24 23 25 29 0 NONE 119
CONECT 25 24 26 27 28 NONE 120
CONECT 26 25 60 61 62 NONE 121
CONECT 27 25 63 64 65 NONE 122
CONECT 28 25 66 67 68 NONE 123
CONECT 29 24 30 69 0 NONE 124
CONECT 30 29 35 31 0 NONE 125
CONECT 31 30 32 33 34 NONE 126
CONECT 32 31 70 71 72 NONE 127
CONECT 33 31 73 74 75 NONE 128
CONECT 34 31 76 77 78 NONE 129
CONECT 35 22 30 36 0 NONE 130
CONECT 36 35 14 0 0 NONE 131
CONECT 37 18 38 79 80 NONE 132
CONECT 38 37 39 81 82 NONE 133
CONECT 39 38 40 83 84 NONE 134
CONECT 40 39 16 85 86 NONE 135
CONECT 41 15 11 87 0 NONE 136
CONECT 42 2 88 89 90 NONE 137
CONECT 43 2 91 92 93 NONE 138
END NONE 139
</inlineContents>
</jmolApplet>
</jmol>

The compound was developed by Professor Jacobsen of Harvard University from around 1990s.

----

==='''Preparation of the catalyst'''===
[[Image: Jacobsen catalyst preparation.gif ]]
----

[[Image:Jacobsen catalyst epoxidation of alekenes.gif|thumb|Description]]

==='''Reference'''===
1. Cepanec, I. I. (2001). "An improved method for synthesis of Jacobsen's catalyst." Synthetic communications 31(19): 2913.

2. Flessner, T. T. (1999). "N,N'-bis(3,5-di-t-butylsalicylidene)-1,2-cyclohexanediaminomanganese(III) chloride. The Jacobsen catalyst." 341(5): 436.

3. Jacobsen, E. N. E. (1991). "Highly enantioselective epoxidation catalysts derived from 1,2-diaminocyclohexane." Journal of the American Chemical Society 113(18): 7063.

4. J. Am. Chem. Soc., Vol 112, No. 7. 1990 - asymmetric epoxidation of alkenes.

5. Acc. Chem. Res. 2000, 33, 421-431.

----
==='''Background'''===
Jacobsen's catalyst(1) is made in 1994 by professor Jacobsen, use in converts achiral olefins to chiral epoxides with enantiomeric excesses regularly better than 90% sometime even higher. To date, the selectivity of this reaction has be understood.

[[image:Transformation1.gif]]
(Figure 1)

Jacobsen's Catalyst is a epoxidation catalysts based on a chiral salen ligand complexed with Manganese(III) (the base salen ligand is drawn in red).

[[image:Jacobsen's_Catalyst(1).gif]]

(Figure 2),Jacobsen's Catalyst (1) and the first salen catalyst introduced by Jacobsen (2)

Jacobsen's catalyst is the most convenient and effective compound for stereoselective synthesis in producing the side chain in the antitumour drug Taxol. Jacobsen has reported a simple large-scale preparation of catalyst,making it readily in large quantity. The reaction requires only a small amount of catalylst to substrate while making use of common bleach which is a low cost oxidant.

There are two related but distinct aspects for the reaction, the oxygen transfer and the chiral induction. However neither aspect can be explained fully.

[[image:Cycle1.gif]]

(Figure 3),The epoxidation occurs by a two step catalytic cycle

The oxygen transfer is known to occur by a two step catalytic cycle (Figure 3), similar to the accepted mechanism of metal porphyrin catalysed epoxidations. An oxidant transfers atomic oxygen to the Mn(III) catalyst in the first step. The oxygen presumably coordinates to the metal in a site normal to the porphyrin or salen plane, and the activated oxygen is then delivered to the alkene. This cycle, as opposed to assisted transfer by a complex aggregate, is supported by observations that several oxidants have been used with identical selectivity, that the reaction consumes stoichiometric quantities of an oxidant in the process of converting an alkene to an epoxide, and that related salen complexes show incorporation of oxygen from in situ labelled water, which does not occur via exchange with the oxidant or epoxide.

Oxygen transfer from the catalyst to the olefin has been hypothesized to occur by several different mechanisms (Figure 4) including attack of an oxygen radical intermediate on the double bond (A), concerted oxygen delivery (B), and formation of a metallaoxetane intermediate (C).

[[image:Modesoxtransfer1.gif]]

(Figure 4),Three possible ways of oxygen delivery

Even thought a mechanism which a metallaoxetane is a plausible intermediate is given by Norrby and coworkers, Jacobsen has demonstrated that it is likely oxidation of different olefins occurs by different mechanisms,it is generally accepted that oxygen transfer to olefins with radical stabilizing groups occurs by an attack of an oxygen centred radical on the olefin. This mode of oxygen delivery is supported by the observation that cis olefins result in both cis and trans epoxides.

The second aspect of the epoxidation mechanism must occur in the second step of the catalytic cycle where oxygen is transferred from the oxo-manganese complex to the epoxide. Fundamental to this stereoselection is the relative orientation of the activated catalyst and the olefin in the first irreversible bond formation.

File:Modesoxtransfer1.gif

2006-10-26T10:43:49Z

Kfl05:

File:Transformation1.gif

2006-10-26T10:42:59Z

Kfl05:

File:Cycle1.gif

2006-10-26T10:40:07Z

Kfl05:

File:Jacobsen's Catalyst(1).gif

2006-10-26T10:39:37Z

Kfl05: