CATALYTIC ENANTIOSELECTIVE ADDITION OF TERMINAL ALKYNES TO ALDEHYDES: PREPARATION OF (S)-(-)-1,3-DIPHENYL-2-PROPYN-1-OL AND (S)-(-)-4-METHYL-1-PHENYL-2-PENTYN-1,4-DIOL
A conformationally restricted perhydro-1,3-benzoxazine derived from (-)-8-aminomenthol behaves as a good chiral ligand in the dimethylzinc-mediated enantioselective monoaddition of aromatic and aliphatic terminal alkynes to 1,2-diketones. The corresponding α-hydroxyketones were...