Silver-catalyzed regioselective direct dichlorotrifluoromethoxylation of terminal alkynes

Abstract

The incorporation of the trifluoromethoxy (OCF₃) group into alkynes remains a topic of ongoing interest in modern organic chemistry. In particular, halo-trifluoromethoxylated alkenes have significant synthetic utility, yet access to dichlorotrifluoromethoxylated variants remains limited, with no general methods available for their direct preparation from simple alkynes. In this study, we present a practical and efficient method for dichlorotrifluoromethoxylation of terminal alkynes, enabling the synthesis of 1,1-dichloro-2-(trifluoromethoxy)alkenes in good to excellent yields (65–95%) under mild reaction conditions. This reaction demonstrates broad substrate tolerance, accommodating various functional groups, and is applicable for the late-stage modification of structurally complex, bioactive molecules. The resulting dichlorotrifluoromethoxylated alkenes serve as versatile synthetic intermediates, providing new opportunities for constructing OCF₃-containing molecular architectures.