Novel addition reactions of titanacycle phosphonates by tuning of Ti(O-i-Pr)(4)/2i-PrMgCl

Di- or tri-substituted vinylphosphonates, 2-5, can be obtained in a highly regio- and stereoselective manner from 1-alkynylphosphonates, by manipulation of Ti(O-i-Pr)(4)/2i-PrMgCl.