Homolytic hydrogermylation of alkenes with dibutylchlorogermane

In the presence of Et3B-dry air, dibutylchlorogermane (Bu2GeClH) reacted smoothly with alkenes at room temperature to give hydrogermylation products in high yields. This homolytic hydrogermylation was applicable to various alkenes including electron-deficient, electron-rich, and internal alkenes. Under the same conditions, tributylgermane (Bu3GeH) showed much lower reactivity than Bu2GeClH. The Et3B-initiated reaction of 1,6-dienes with Bu2GeClH gave germylmethylated cyclopentanes.