Nickel-catalyzed alkenylation Grignard compound

Transition metal-catalyzed cross-coupling reactions between vinyl organometallic compounds and unactivated alkyl halides that can be usually performed with palladium, nickel and cobalt are of particular synthetic interest [37-39]. Recently, the groups of Cahiez [48] and Cossy [49] concurrently reported the first iron-catalyzed reaction of alkenyl Grignard compounds with primary and secondary alkyl halides (X=Br, I) (Scheme 5.15). The two protocols basically differ in the iron source... 

Fig. 16.10. Nickel-catalyzed alkenylation of Grignard compounds occurrence of stereoselectivity and stereospecificity.

Low-valent nickel species catalyze the reaction between Grignard reagents and aryl or alkenyl sulfide in the preparation of alkylarenes, biaryls, and alkenes (see citations in Ref. ///). Wenkert et al. recently isolated compounds 132 and 133 to show that an oxidative addition occurs between diaryl sulfides and tris(tri-/ -butyl)phosphinonickel (77/). 

---