Highly (E)-selective BF(3).Et(2)O-promoted allylboration of chiral nonracemic alpha-substituted allylboronates and analysis of the origin of stereocontrol.
Delta-methyl-substituted homoallylic alcohols 2 were prepared in 71-88% yield, E:Z >30:1 and 93% to >95% ee via BF(3).Et(2)O-promoted allylboration with alpha-Me-allylboronate 1. The origin of high (E)-selectivity is proposed.
Chen
Ming
M
Department of Chemistry, Scripps Florida, Jupiter, Florida 33458, USA.
Roush
William R
WR
D000438:Alcohols / Q000138:chemical synthesis* / Q000737:chemistry; D000447:Aldehydes / Q000737:chemistry; D000498:Allyl Compounds / Q000737:chemistry*; D001897:Boronic Acids / Q000737:chemistry*; D002384:Catalysis; D020650:Combinatorial Chemistry Techniques; D015394:Molecular Structure; D013237:Stereoisomerism
D000438:Alcohols; D000447:Aldehydes; D000498:Allyl Compounds; D001897:Boronic Acids