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Updated: Mar 3, 2026
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Sequential catalysis: exploiting a single rhodium(i) catalyst to promote an alkyne hydroacylation-aryl boronic acid
Maitane Fernández1, Matthias Castaing1, Michael C Willis1
1Department of Chemistry , University of Oxford , Chemical Research Laboratory , Mansfield Road , Oxford , OX1 3TA , UK .
Abstract:
We demonstrate that a single Rh(i) complex can promote two mechanistically distinct C-C bond-forming reactions - alkyne hydroacylation and aryl boronic acid conjugate addition - to deliver substituted ketone products from the controlled assembly of three readily available fragments. This is a rare example of a Rh(i)/Rh(iii) cycle and a redox neutral Rh(i) cycle being promoted by a single catalyst. The process is broad in scope, allowing significant variation of all three reaction components. Incorporation of an enantiomerically pure bis-phosphine ligand renders the process enantioselective. Superior levels of enantioselectivity (up to >99% ee) can be achieved from using a two catalyst system, whereby two Rh(i) complexes, one incorporating an achiral bis-phosphine ligand and the second a chiral diene ligand, are introduced at the start of the reaction sequence.
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