Enantioselective Additions of Stabilized Carbanions to Imines Generated from ?-Amido Sulfones By Using Lipophilic Salts of Chiral Tris(1,2-diphenylethylenediamine) Cobalt(III) Trications as Hydrogen Bond Donor Catalysts Academic Article uri icon

abstract

  • The enantiopure salt -[Co((S, S)-dpen) 3 ] 3+ 2Cl - BAr f- [BAr f = B(3,5-C 6 H 3 (CF 3) 2) 4 ] is an effective hydrogen bond donor catalyst (10 mol%, r.t., CH 2 Cl 2) for enantioselective additions of dialkyl malonates to Boc-derivatized aryl imines generated from sulfones [ArCH(SO 2 Ph)NHBoc] in the presence of K 2 CO 3 (ten examples, 91-97% isolated yields, 87-99% ee). The diastereomeric salt Λ-[Co((S, S)-dpen) 3 ] 3+ 2Cl - BAr f20- [BAr f20- = B(C 6 F 5) 4- ] is similarly applied to additions of nitroalkanes (four examples, 89-93% isolated yields, 79-91% ee). Precautions to exclude air or moisture are unnecessary.

altmetric score

  • 1

author list (cited authors)

  • Joshi, H., Ghosh, S., & Gladysz, J.

citation count

  • 12

publication date

  • June 2017