Reductive Homocoupling of Organohalides Using Nickel(II) Chloride and Samarium Metal

Abstract

A homocoupling method for organohalides and organosulfonates promoted by samarium metal and HMPA, and catalyzed by NiCl has been developed. Various organohalides (benzyl, aryl, heterocyclic, alkenyl and alkyl halides), α-haloacetophenones, and phenyl organosulfonates were tolerated, and the reaction afforded coupling products with high efficiency. Excellent chemoselectivity was exhibited between halides and other groups, such as -COOH, -NO , halogen, heterocyclic ring, ester, and ketone groups. The stereoselectivity suggested that the reaction mechanism might involve an organosamarium species.

A Highly Stable Porous Viologen Polymer for the Catalysis of Debromination Coupling of Benzyl Bromides with High Recyclability

“…Selective reductive coupling of benzyl bromides to the corresponding 1,2‐diphenylethanes in high yields has been realized by using SmI 2 , vitamin B12, Mn 2 (CO) 10 , Fe(acac) 3 , Cp 2 TiCl, Re(Br)(H)(NO)(PCy 3 ) 2 , NiCl 2 (glyme)/terpyridine, NiCl 2 (PPh 3 ) 2 , RhCl(PPh 3 ) 3 , Co(PMe 3 ) 4 /Me 2 Zn, and NiCl 2 /Sm . However, recyclable heterogeneous catalysis of these two reactions have not been reported in the literature.…”

“…4,4′‐(sulfonylbis(methylene))bis(methylbenzene) ( 2 c ) . White solid, 12.9 mg, 94% yield; 1 H NMR (400 MHz, CDCl 3 ): 7.29 (d, J =8.0 Hz, 4H), 7.23 (d, J =8.0 Hz, 4H), 4.08 (s, 4H), 2.39 (s, 4H); 13 C NMR (100 MHz, CDCl 3 ): 139.0, 130.7, 129.7, 124.5, 56.9, 21.9; HRMS (ESI): Calcd for [M+NH 4 ] + 292.1371, Found: 292.1377.…”

Organic Synthesis with Elemental Lanthanides – Going Beyond Samarium and Ytterbium

“…Sm/Ni system for homocoupling of aryl and benzylhalides. [65] Scheme 35. Synthesis of furofuran lignans using a Sm/CuI system.…”

Copper‐Catalyzed Homocoupling of Alkyl Halides in the Presence of Samarium

“…Long‐term preservation of SmI 2 is another difficulty owing to its sensitity to air and moisture. By comparison, the direct use of samarium metal has the advantages of simple operation, atom economy, cheap and easy storage –…”