Enantioselective construction of C-chiral allylic sulfilimines via the iridium-catalyzed allylic amination with S,S-diphenylsulfilimine: asymmetric synthesis of primary allylic amines

Abstract

We have devised a highly regio- and enantioselective iridium-catalyzed allylic amination reaction with the sulfur-stabilized aza-ylide, S,S-diphenylsulfilimine.

Sulfilimines as Versatile Nitrene Transfer Reagents: Facile Access to Diverse Aza‐Heterocycles

“…[10] In contrast to this,t he study of their nitrogen analogues, sulfilimines, [11] remains comparatively underdeveloped, especially in gold chemistry.C ompared with other nucleophilic nitrenes,s ulfilimines feature inexpensive and easy syntheses, [12] and owing to the strong polarization towards the nitrogen atom, these building blocks can emerge as valuable synthetic intermediates by N À Sb ond cleavage. [13] Nevertheless,tothe best of our knowledge,this versatile and promising metal nitrene precursor has never been successfully applied as ag old carbene precursor although N-sulfonyl sulfilimines were employed by Zhang and co-workers [4b] for the synthesis of a,b-unsaturated amidines (only 2e xamples) in less than 35 %y ield and quite moderate E/Z ratios of 1.5:1 to 2:1. Inspired by previous reports [14] and in line with our interests on gold-catalyzed CÀHannulations (NÀObond cleavage for nitrene transfer), [7b,d,g] we envisioned the generation of a-imino gold carbenes from sulfilimines and ynamides, which could be flexibly and divergently trapped with four types of functional groups attached to either the sulfilimine or ynamide to form four different aza-heterocycles (Scheme 1).…”

Synthesis of Chiral Homoallylic Nitriles by Iridium-Catalyzed Allylation of Cyanoacetates

“…Ester 1l was prepared according to the literature . Ester 1g was prepared according to the literature . Ester 1l was prepared by the reaction of ( E )-5-phenyl-2-penten-1-ol with methyl chloroformate.…”

An Overview of Iridium‐Catalyzed Allylic Amination Reactions

“…Evans and co‐workers proposed the Ir‐catalyzed allylic amination of S,S ‐diphenylsulfilimine and also demonstrated that azaylides are valuable class of nucleophiles for both regioslective and enantioselective Ir‐catalyzed allylic amination reaction [68] . Allylic carbonates and benzoates reacted with S,S ‐diphenylsulfilimine and chiral Ir complex derived from [Ir(cod)Cl] 2 and phosphoramidite ligand to form chiral non‐racemic N‐allylic sulfilimines.…”