Practical preparation of methyl vinyl ethers through the direct coupling of ketones with CHCl₂OMe promoted by Mg/TiCl₄/THF

Herein we utilized a new methylene carbenoid as an extremely simple and highly practical reagent for the preparation of vinyl ether with good to excellent yield. This method efficiently effects methoxymethylenation or vinyl ether formation of enolizable, nonenolizable, and sterically hindered ketones. The complexation of Ti–Mg–CHOMe was facilitated, presumably, by THF dramatically increasing the feasibility; and scope of this protocol is to produce vinyl ethers which can be used as convenient building blocks for the preparation of biologically useful molecules.