Trimethylsilylacetylene → 2-benzylthio-7-trimethylsilylethynyl-5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-one

Participants

Reaction Steps

In a mixture of 30 ml of triethylamine and 60 ml of tetrahydrofurane, 7.0 g of the thus obtained 55% pure 2-benzylthio-7-iodo-5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-one was dissolved, and 0.68 g of bis(triphenylphosphine)palladium (II) chloride and 0.18 g of cuprous iodide were added to the solution. A solution of 3.8 g of ethynyltrimethylsilane in 20 ml of triethylamine was added dropwise to the above solution, the resulting solution was heated to 68°-70° C. and stirred for 4 hours. After cooling, the reaction mixture was filtered, and the filtrate was concentrated under reduced pressure. The residue was separated by silica gel column chromatography using an ethyl acetate/hexane mixture as an eluent, and thus 4.2 g of 2-benzylthio-7-trimethylsilylethynyl-5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-one was obtained.

Provenance & Evidence