Highly selective addition reaction of organotitaniums with Garnerʹs aldehyde. Easy preparation of optically active allylic, allenylic, homoallylic and homopropargylic alcohols

Organotitanium complexes 3–5 prepared from a Ti(O-i-Pr)4/2/i-PrMgX reagent (2) and the corresponding unsaturated compounds reacted with Garnerʹs aldehyde (1) to provide anti-addition products highly predominantly, thus allowing an easy access to a variety of optically active anti-1,2-aminoalcohol derivatives.