Diastereoselective addition reactions of furyl aldehydes using chiral boronates as auxiliary: application to the enantioselective synthesis of 2,3-disubstituted furyl alcohols.
[reaction: see text] The addition reactions of various nucleophiles to a furyl aldehyde bearing a chiral boronate at the C-3 position furnished chromatographically separable diastereomers. The R diastereoselection was more favorable when no additive was added. Surprisingly, when lithium alkoxides were selected as additives, the S diastereoselection is superior instead. Further transformation of C-B bonds to C-C bonds was achieved by using standard Suzuki coupling conditions to give optically active 2,3-disubstituted furyl alcohols.
Chan
K F
KF
Department of Chemistry and Central Laboratory of the Institute of Molecular Technology for Drug Discovery and Synthesis, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China.
Wong
H N
HN
D000438:Alcohols / Q000138:chemical synthesis* / Q000737:chemistry; D000447:Aldehydes / Q000737:chemistry*; D001897:Boronic Acids / Q000737:chemistry*; D018360:Crystallography, X-Ray; D018020:Lithium Compounds / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D015394:Molecular Structure; D010084:Oxidation-Reduction; D013237:Stereoisomerism
D000438:Alcohols; D000447:Aldehydes; D001897:Boronic Acids; D018020:Lithium Compounds