Chiral synthesis via organoboranes. 36. Exceptionally enantioselective allylborations of representative heterocyclic aldehydes at -100 .degree.C under salt-free conditions
作者:Uday S. Racherla、Yi Liao、Herbert C. Brown
DOI:10.1021/jo00050a045
日期:1992.11
Chiral terpenyl-based allylborane reagents (Ter2*BCH2CH=CH2, 1-3) undergo facile condensation with representative heterocyclic aldehydes (HetCHO) at -100-degrees-C (in the absence of Mg2+ salts) and afford the corresponding homoallylic alcohols (HetCH*(OH)CH2CH=CH2,12-19) in enantiomeric purities approaching 100% ee. A new workup procedure involving 8-hydroxyquinoline (8-HQ) has been utilized for the convenient isolation of the product alcohols.
RACHERLA, UDAY S.;BROWN, HERBERT C., J. ORG. CHEM., 56,(1991) N, C. 401-404