Double Addition of Propargylzinc Reagents to Acylcyanohydrins and Cyanocarbonates

Two darts in the middle! This work reports double addition of propargylzinc reagents to nitriles (acylcyanohydrins and cyanocarbonates). methodology provides a straightforward access dipropargylic α,α-disubstituted hydroxyamides or N-Boc-protected amino alcohols which can be converted into functionalized pyridine derivatives after cobalt-catalyzed [2+2+2] cycloaddition reactions involving nitriles.