Development of visible light mediated photocatalytic alkynylation of hydrogermanes

Abstract

Alkynylgermanes are a kind of essential synthetic block in organic chemistry. The established synthetic routes retain some drawbacks regarding harsh reaction conditions and expensive (or rare) metal catalysts. A mild and efficient photocatalytic method for the synthesis of value-added alkynylgermane is developed without using an excess of reagents. We employed ((phenylethynyl)sulfonyl) benzene and triphenylgermanium hydride as basic substrates, 4CzIPN as the organophotocatalyst, and N-cyclohexyl-4-methyl-benzenesulfonamide as hydrogen atom transfer (HAT) catalyst. Further, we extended our study to a number of substrates to check the scope of our reaction for the synthesis of alkynylsilane.