A Facile Synthesis of 3H-Benzo[1,2]Dithiole-3-Thiones and Their Condensation with Active Methylene Compounds

Abstract

3H-Benzo[1,2]-dithiole-3-thiones were prepared from potassium sulfide and 2-halobenzaldehydes in moderate-to-good yields, and a plausible mechanism for this catalyst-free intramolecular heteroannulation reaction has been proposed. The Knoevenagel condensation reactions of 3H-benzo[1,2]dithiole-3-thiones with active methylene compounds such as ethyl 2-cyanoacetate and diethyl malonate, and the three-component one-pot reactions of potassium sulfide, 2-halobenzaldehydes, and ethyl 2-cyanoacetate, affording the corresponding products, have been developed.

GRAPHICAL ABSTRACT      

Acceleration test of substrate-packaged fiber Bragg grating sensor北大核心CSCD

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