Nickel catalyzed cross-coupling of modified alkyl and alkenyl Grignard reagents with aryl- and heteroaryl nitriles: activation of the CCN bond

Cobalt-Catalyzed C(sp2)–CN Bond Activation: Cross-Electrophile Coupling for Biaryl Formation and Mechanistic Insight

“…14,16 Among metals reported to activate C(sp 2 )-CN bonds, Ni, Rh and Pd have been mainly applied in catalysis. 7,9b,17 Notably, in cross-coupling reactions, 18 apart from a particular cross-coupling between benzonitrile and azole derivatives, 19 thus, necessitating to employ a nickel(0)/alkyl phosphine catalyst to be able to activate the C(sp 2 )-CN bond via pathway A, biaryl formation from benzonitriles has been reported using nickel catalyst with organometallic coupling partners 20 such as aryl Grignard reagents, 21,22 arylboronic esters 23 as well as arylmanganese compounds (Scheme 1b). 24 The use of such organometallic species makes easy the reduction of nickel(II)/alkyl phosphines pre-catalysts into nickel(0) active species, which can then insert into the C(sp 2 )-CN bond according to pathway A.…”

Biaryl Formation Involving Carbon‐Based Leaving Groups: Why Not?

“…2‐thiophenecarbonitrile, 2‐pyridinecarbonitrile) in >70 % yield. At present, the method cannot compete with the Kumada coupling7 using aryl halides, although aryl cyanides have found an elegant application in related reactions, in particular in the nickel‐catalyzed cross‐coupling with alkynylzinc6c and alkenyl Grignard6d reagents to form the corresponding aryl alkynes and aryl alkenes.…”

Arylcyclopropanes: Properties, Synthesis and Use in Medicinal Chemistry

“…Using a nickel catalyst, the corresponding arylcyclopropane 22 was obtained in modest yield (Scheme 26). 74,75 In order to minimize the amount of Scheme 26 nucleophilic addition to the nitrile group during the cross-coupling event, the Grignard reagent was modified by the addition of t-BuOLi (reagent 87a) or PhSLi (reagent 87b). A survey of the catalyst indicated that NiCl 2 (PMe 3 ) 2 was generally superior to other nickel or palladium catalysts.…”