Enantioselective Homoallenylation of Aldehydes

Significance

Despite their utility, few general methods exist for the synthesis of β-allenols. The authors report the first highly enantioselective ­catalytic homoallenylation of aldehydes to access this valuable class of substrates. This Nozaki-Hiyama-Kishi (NHK) reaction achieves excellent enantioselectivity through the use of a C ₁-symmetric bisoxazoline ligand previously developed and applied to allylation and crotylation reactions (P. J. Guiry and co-workers Adv. Synth. Catal. 2006, 348, 551).