Ligand‐Free Copper‐Catalyzed Negishi Coupling of Alkyl‐, Aryl‐, and Alkynylzinc Reagents with Heteroaryl Iodides

Abstract

Reported herein is an unprecedented ligand-free copper-catalyzed cross-coupling of alkyl-, aryl-, and alkynylzinc reagents with heteroaryl iodides. The reaction proceeds at room temperature for the coupling of primary, secondary, and tertiary alkylzinc reagents with heteroaryl iodides without rearrangement. An elevated temperature (100 °C) is required for aryl-heteroaryl and alkynyl-heteroaryl couplings.

Copper-catalyzed arylation of alkyl halides with arylaluminum reagents

“…Recently, we [ 23 – 27 ] and others [ 10 , 28 – 39 ] reported efficient cross-couplings of oganometallic reagents of Si, B, In, Zr, Zn, Mg and Sn with organo halides [ 40 – 41 ]. Under our reaction conditions, a catalyst derived from the combination of CuI and 2-(diphenylphosphino)- N , N -dimethylaniline (PN-1) remains highly effective for coupling many of these organometallic reagents with aryl halides.…”

Emergence of Copper‐Mediated Formation of C–C Bonds

“…In 2015, Giri et al reported cross‐coupling between alkyl‐, aryl‐, or alkynylzinc halides and heteroaryl halides . The reactions proceeded in the presence of catalytic amounts of copper iodide, together with lithium chloride, in N , N ‐dimethylformamide at room temperature.…”

Transmetalation of Alkylzirconocenes in Copper‐Catalyzed Alkyl–Alkynyl Cross‐Coupling Reactions

“…reported the use of Grignard reagents in alkyl–alkynyl cross‐coupling reactions using catalytic CuI . Giri and co‐workers documented their findings about copper‐catalyzed alkyl–alkynyl cross‐coupling reactions of alkynylzinc reagents with heteroaryl iodides . Knochel and Normant separately published copper‐mediated cross‐coupling reactions between alkylcuprates and alkynyl halides.…”