ORGN 134 |
| The desymmetrisation of cyclic C2-symmetric bis-vinyltriflates via palladium-catalysed carbonylation to produce chiral monoesters is reported. A number of catalysts with binapthyl-based hemilabile bidentate ligands were used to discriminate between the two enantiotopic faces of the molecule. This afforded a range of monoesters containing a newly formed chiral quarternary carbon centre in up to 96% ee. These are synthetically useful substrates that provide the opportunity to introduce further functional groups via derivatisation of the remaining vinyltriflate group. The scope and key features of the reaction were investigated via a range of substrates with varying aryl/aliphatic groups of differing electronic and steric nature (RA, RB), ring sizes (n), nucleophiles and activating groups (e.g. OTf, ONf). Intramolecular variants were also performed to yield the corresponding lactones
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Asymmetric Reactions and Syntheses, Metal-Mediated Reactions, Combinatorial, Parallel, and Solid-Phase Chemistry
8:00 PM-10:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster
Division of Organic Chemistry |
