Remarkable Rate Acceleration of Pd(0)-Catalyzed Hydrogermylation of Alkynes and Dienes in Water

Abstract

[reaction: see text] Without the use of hydrophilic cosolvents or phase transfer catalysts, Pd(0)-catalyzed hydrogermylation of alkynes in water provides dienylgermanes efficiently with high stereo- and regioselectivity. The reaction in water proceeds much faster than the reaction under neat conditions. By using an aqueous system, hydrogermylation can be conducted at a low catalyst loading.

Catalyzed Reactions of Alkynes in Water

“…(49)]. [115] It is worth noting that the reaction in water proceeded much faster than in organic solvents or under neat conditions. In addition, in an aqueous system, the catalyst loading could be as low as 0.0025 mol %.…”

New synthetic routes to allylic germatranes

“…Palladium-catalyzed hydrogermylation of terminal acetylenes by triphenyl germane, giving E-triphenylgermyl alkenes [13], and of isoprene by tri(2-furyl)germane [14] proceeds in both cases in good yield with marked stereochemical selectivity. We reasoned that allylic germatranes might also be prepared by the germatrane hydrogermylation of the corresponding dienes, Scheme 2.…”

Recent advances in the use of tri(2-furyl)germane, triphenylgermane and their derivatives in organic synthesis

“…9. Palladium-catalyzed hydrogermylation of alkynes with tri(2-furyl)germane in water providing dienyltri(2-furyl)germane [32] We reported in 1987 that palladium-catalyzed reaction of 1-alkyne (1.0 equiv) with triphenylgermane (1.2 equiv) provided a mixture of alkenylgermanes (Scheme 31) [16f]. We thus reexamined the hydrogermylation of 1-alkyne with Fu 3 GeH.…”