Synthesis of benzylic sulfones
In the absence of external catalysts and additives, a broad range of benzylic and allylic alcohols react with various sulfinyl chlorides to afford structurally diversified benzylic and allylic sulfones in moderate to excellent yields. A catalysis with byproduct HCl is involved in this new protocol.
H.-H. Li, D.-J. Dong, Y.-H. Jin, S.-K. Tian, J. Org. Chem., 2009, 74, 9501-9504.
A palladium complex generated in situ from [Pd(η3-C3H5)Cl]2 and DPEphos [bis(2-diphenylphosphinophenyl)ether] catalyzed the nucleophilic substitution of benzylic carbonates with sodium arenesulfinates in DMSO at 80°C. The reaction gave a variety of benzylic sulfones in high yields.
R. Kuwano, Y. Kondo, T. Shirahama, Org. Lett., 2005, 7, 2973-2975.
Thiosulfonates synthesized by copper-catalyzed aerobic dimerization serve as substrate for simple and high-yielding strategies for the production of a variety of sulfones and sulfonamides. Thiosulfinates are stable, nontoxic alternatives to metal sulfinate salts derived from toxic SO2.
P. K. Shyam, H.-Y. Jang, J. Org. Chem., 2017, 82, 1761-1767.
Treatment of methylarenes with 1,3-dibromo-5,5-dimethylhydantoin or N-bromosuccinimide and a catalytic amount of 2,2′-azobis(isobutyronitrile) followed by a reaction with a nucleophile, such as benzoic acid, p-toluenethiol, sodium p-toluenesulfinate, aqueous dimethylamine, or succinimide, provides the corresponding benzylated products in good yields.
H. Shimojo, K. Moriyama, H. Togo, Synthesis, 2015, 47, 1280-1290.
The addition of Grignard reagents or organolithium reagents to the SO2-surrogate DABSO generates a diverse set of metal sulfinates, which can be trapped in situ with a wide range of C-electrophiles, including alkyl, allyl, and benzyl halides, epoxides, and (hetero)aryliodoniums to give sulfone products.
A. S. Deeming, C. J. Russell, A. J. Henessy, M. C. Willis, Org. Lett., 2014, 16, 150-153.
A one-pot synthesis of aryl sulfones from primary alcohols is described. Alcohols were treated with N-bromosuccinimide and triphenylphosphine, followed by addition of sodium arenesulfinate with a catalytic amount of tetrabutylammonium iodide to afford the aryl sulfones in good to high yields.
T. Murakami, K. Furusawa, Synthesis, 2002, 479-482.
Ni-catalyzed stereoconvergent Negishi arylations and alkenylations of racemic α-bromosulfonamides and -sulfones furnish cross-coupling product in very good ee and yield for an array of reaction partners. Mechanistic studies are consistent with the generation of a radical intermediate.
J. Choi, P. Martín-Gago, G. C. Fu, J. Am. Chem. Soc., 2014, 136, 12161-12165.