α,α-Difluoro-substituted organozinc reagents generated from conventional organozinc compounds and difluorocarbene couple with 1-bromoalkynes affording gem-difluorinated alkynes. The cross-coupling proceeds in the presence of catalytic amounts of copper iodide in dimethylformamide under ligand-free conditions.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4660974PMC
http://dx.doi.org/10.3762/bjoc.11.231DOI Listing

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