810677-19-1Relevant articles and documents
Allyl 4-Chlorophenyl Sulfone as a Versatile 1,1-Synthon for Sequential α-Alkylation/Cobalt-Catalyzed Allylic Substitution
Kojima, Masahiro,Matsunaga, Shigeki
, p. 1934 - 1946 (2020/07/03)
Despite their unique potential as rare 1,1-dipole synthons, allyl sulfones are rarely used in target-oriented syntheses, likely due to the lack of a general catalytic method for their branch-selective allylic substitution. Herein, we identified allyl 4-chlorophenyl sulfone as a versatile linchpin for both base-mediated α-derivatization and subsequent cobalt-catalyzed allylic substitution. The sequential transformations allow for highly regioselective access to branched allylic substitution products with a variety of aliphatic side chains. The photoredox-enabled cobalt catalysis is indispensable for achieving high yields and regioselectivity for the desulfonylative substitution in contrast to traditional metal-catalyzed protocols, which lead to inferior outcomes in the corresponding transformations.
Thiourea-Catalyzed Enantioselective Malonate Addition onto 3-Sulfonyl-3′-indolyl-2-oxindoles: Formal Total Syntheses of (-)-Chimonanthine, (-)-Folicanthine, and (+)-Calycanthine
Babu, K. Naresh,Roy, Avishek,Singh, Manvendra,Bisai, Alakesh
, p. 6327 - 6331 (2018/10/20)
A general approach to bispyrroloindolines via a key thiourea-catalyzed addition of malonates to 3-sulfonyl-3′-indolyl-2-oxindoles is reported. The enantioselelective process is found to be highly effective (up to 94% ee), where a C-C bond formation leads
