title: Nickel 0-catalyzed cross-coupling of alkyl arenesulfonates with aryl Grignard reagents.
abstract: The nickel-catalyzed cross-coupling reactions of neopentyl arenesulfonates with arylmagnesium bromides, involving nucleophilic aromatic substitution of alkyloxysulfonyl groups by aryl nucleophiles, take place in high yields. Optimal efficiencies are obtained by adding 3 + 2 equiv of the Grignard reagent to a mixture of dppfNiCl(2) and the sulfonate in refluxing THF. Neopentyl arenesulfonates are useful sources of the electrophilic aryl groups in these transition metal-catalyzed cross-coupling reactions. Aryl sulfonates are inappropriate due to their ambident reactivity under the reaction conditions. This new cross-coupling reaction can be used for the creative elimination of alkyloxysulfonyl groups from aromatic compounds and for the preparation of unsymmetric terphenyls and oligophenyls.
authors.affiliation: Department of Chemical Engineering, Chung-Ang University, Huksuk-Dong 221, Dongjak-Ku, Seoul 156-756, South Korea.
authors.forename: Chul-Hee
authors.initials: CH
authors.lastname: Cho
authors.forename: Hee-Sung
authors.initials: HS
authors.lastname: Yun
authors.forename: Kwangyong
authors.initials: K
authors.lastname: Park