A Convenient Method for the Preparation of Secondary Propargylic Ethers. The Reaction of Acetals with 1-Trimethylsilylalkynes Promoted by the Combined Use of Catalytic Amounts of Tin(IV) Chloride and Zinc Chloride
In the coexistence of catalytic amounts of SnCl4 and ZnCl2, acetals undergo a coupling with 1-trimethylsilylalkynes in good yields to give secondary propargylic ethers, which are also directly produced from aldehydes by the reaction with alkoxytrimethylsilanes and 1-trimethylsilylalkynes under the same conditions.