C O M M U N I C A T I O N S
Scheme 1a
with no obvious coordinating groups.23 As in the syntheses of
1,3-dimethyl-,15-17 1,3-hydroxymethyl-,24 and 1,2-hydroxymethyl-25
synthons, the key issue tends to be enhancement of catalyst control
by adjusting the substrate Vector by changing peripheral masking or
functional groups. Throughout, the range of substrates that can be
processed with high selectivities is less important than finding the right
situation to prepare privileged chirons that are ubiquitously useful in
syntheses of optically active molecules. The Roche ester and catalyst
1 are available as both optical antipodes so the methodology described
here achieves this for R,ω-functionalized 1,2-dimethyl chirons.
Acknowledgment. Financial support for this work was provided
by The National Science Foundation (CHE-0750193) and The
Robert A. Welch Foundation.
Supporting Information Available: Experimental data for the new
compounds reported. This material is available free of charge via the
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