Chemo-, regio-, and stereoselective hydroboration of conjugated enyne alcohol/amine: facile synthesis of Z , Z -/ Z , E -1,3-dien-1/2-ylboronic ester bearing hydroxyl/amino group
Hydroboration of conjugated enyne alcohol/amine is studied by using copper salts and bis(pinacolato)diboron as pre-catalysts and boron source respectively. It is suggested that the chemo-selectivity is derived from a combined electronic influence of the heteroatoms on the substrate and the ligand on the transition metal. The regioselectivity is probably dominated mainly by electronic effect of the
作者:Stephen Caddick、Sakthitharan Shanmugathasan、Denis Brasseur、Vern M Delisser
DOI:10.1016/s0040-4039(97)01259-8
日期:1997.8
The presence of the p-methoxyphenyl protecting group enables the asymmetric dihydroxylation of homoallylic enynols to be carried out in good yield and with high levels of enantioselectivity.