2-Zincoethylzincation of 2-Alkynylamines and 1-Alkynylphosphines Catalyzed by Titanium(IV) Isopropoxide and Ethylmagnesium Bromide

Abstract

Titanium(IV) isopropoxide and ethylmagnesium bromide catalyzed reaction of 2-alkynylamines with Et₂Zn, followed by deuterolysis/hydrolysis and iodinolysis, affords substituted (Z)-pent-2-en-2,5-d ₂-1-amines, (Z)-pent-2-en-1-amines (65–88%), and substituted (Z)-2,5-diiodopent-2-en-1-amines (55–63%). It is suggested that the reaction proceeds through the formation of cyclic organotitanium derivatives. The reaction between 1-alkynylphosphines and Et₂Zn in the presence of catalytic amounts of Ti(O-iPr)₄ and EtMgBr leads to trisubstituted 1-alkenylphosphine oxides with high regioselectivity and stereoselectivity.

Key words

2-alkynylamines - 1-alkynylphosphines - 2-zincoethylzincation - titanium catalysis

• References and Notes

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