Cu-Catalyzed Fe-Driven Csp-Csp and Csp-Csp2 Cross-Coupling: An Access to 1,3-Diynes and 1,3-Enynes
Sabir Ahammed, Debasish Kundu and Brindaban C. Ranu*
*Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India, Email: ocbcriacs.res.in
S. Ahammed, D. Kundu, B. C. Ranu, J. Org. Chem., 2014, 79, 7391-7398.
DOI: 10.1021/jo5011069 (free Supporting Information)
An efficient cross-coupling of alkynyl bromides and boronates to produce unsymmetric 1,3-diynes is catalyzed by CuFe2O4 nanoparticles in dimethyl carbonate. The protocol also enables a coupling of alkynyl bromides and alkenyl boronic acids to provide conjugated 1,3-enynes. The catalyst was easily separated by an external magnet and recycled 10 times.
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