Synthesis of Enynones from Alkynes,Alkynyl Ketones and Aromatic Aldehydes Using the TiCl 4 /Et 3 N Reagent System †

Abstract

Alkynyltitanium species, prepared in situ from alk-1-ynes using the TiCl₄/Et₃N reagent system, react with aromatic aldehydes to give enynones 2 in 49–38% yields. Reaction of alkynyl aryl ketones with aromatic aldehydes and the TiCl₄/Et₃N reagent gives the enynones 2 in 78–92% yields.

Keywords

alkynyl aryl ketones titanium tetrachloride triethylamine enynones

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