Enantioselective Rh/Cu-Catalyzed Addition of Terminal Alkynes to Allenes for the Synthesis of Chiral 1,4-Enynes
Martin Daiger1, Janika Kromer1, Samuel Kaplan1
1Institut für Organische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstraße 21, 79104 Freiburg im Breisgau, Germany.
Abstract:
A regio- and enantioselective rhodium/copper-catalyzed coupling of readily available terminal alkynes and allenes is reported. This method enables direct, atom-economic access to chiral 1,4-enynes, a versatile class of compounds widely employed in the synthesis of natural products and pharmaceuticals. The transformation proceeds in high yields with excellent enantioselectivities and displays broad functional-group tolerance. The synthetic utility of the resulting products is further demonstrated through a range of downstream functionalizations that exploit the orthogonal reactivity of the alkyne and alkene moieties.
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