Under the conditions of transfer hydrogenation utilizing chromatographically purified ortho-cyclometallated iridium C,O-benzoate precatalysts, enantioselective carbonyl crotylation and methallylation can be performed in the absence of stoichiometric metallic reagents and stoichiometric chiral modifiers. In the case of carbonyl crotylation, use of a preformed precatalyst rather than an in situ generated catalyst results in lower reaction temperatures, providing generally higher diastereoselectivity and yields. By utilizing a more reactive leaving group in chloride over acetate on our methallyl donor, the inherently shorter lifetime of the olefin π-complex is compensated for, giving our group’s first report of reactivity utilizing 1,1-disubstituted allyl donors. / text
Identifer | oai:union.ndltd.org:UTEXAS/oai:repositories.lib.utexas.edu:2152/ETD-UT-2012-05-5582 |
Date | 19 July 2012 |
Creators | Townsend, Ian A. |
Source Sets | University of Texas |
Language | English |
Detected Language | English |
Type | thesis |
Format | application/pdf |
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