ATTAQUE NUCLEOPHILE DU CARBONE CENTRAL DE L'ENCHAINEMENT CUMULE LORS DE LA CYCLISATION DE DIOLS ω,ω'-ALLENIQUES

Article abstract of DOI:10.1016/S0040-4039(00)84118-0

The cyclisation of allenic diols 3 and 4 in the presence of mercuric chloride or silver nitrate leads exclusively or predominantly to bicyclic acetals 6 and 8 resulting from an initial nucleophilic attack on the central allenic carbon.This regioselectivity depends on the presence of a terminal methylene in the unsaturation since diol 5 leads to the dihydropyrane 12 coming from the nucleophilic attack on the terminal allenic carbon.