Regiodivergent Hydrogermylation of Alkynes Enabled by Dinuclear Cobalt Catalysts Bearing Different Ligands
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Updated: Jun 10, 2026
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Zungui Zhao1,2, Qingshan Wang1,3, Xuebing Leng1
1State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China.
Abstract:
Transition-metal-catalyzed hydrogermylation of alkynes represents an ideal atom-economical method to prepare vinylgermanes that are valuable reagents in medicinal chemistry, material science and organic synthesis. Nevertheless, its development-particularly in achieving high regioselectivity with earth-abundant 3d metal catalysts-remains as a formidable challenge. Herein, we report regiodivergent hydrogermylation reactions of alkynes employing structure well-defined dicobalt carbonyl complexes as catalysts: the reaction using [(IPent)Co2(CO)7] (IPent = 1,3-di(2,6-di(pentan-3-yl)phenyl)imidazol-2-ylidene) affords selectively α-vinylgermanes, whereas that with [(Xantphos)Co2(CO)6] (Xantphos = (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphane) yields selectively β-(E)-vinylgermanes. Both cobalt catalysts effect the hydrogermylation of alkyl- and aryl-substituted terminal alkynes with tertiary hydrogermanes with good functional group compatibility in good to high yields and selectivity. Mechanistic studies establish alkyne-bridged dicobalt carbonyl species as the active intermediates in both catalytic systems and the distinct steric nature of the metalloligands LCo (L = IPent, Xantphos) governs the observed regiodivergent selectivity. The application of these dicobalt-catalysts to alkyne hydroelementation reactions allows the selective preparation of different configurational isomers of vinylgermanes/silanes that can be further utilized for the stereoselective synthesis of alkene derivatives.
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