Chiral sulfoxides in the enantioselective allylation of aldehydes with allyltrichlorosilane: a kinetic study

Abstract

The mechanism of the allylation of aldehydes in the presence of allyltrichlorosilane employing the commercially available (R)-methyl p-tolyl sulfoxide as a Lewis base has been investigated. The combination of kinetic measurements, conductivity analysis and quantum chemical calculations indicates that the reaction proceeds through a dissociative pathway in which an octahedral cationic complex with two sulfoxides is involved. The lack of turnover is ascribed to the formation of neutral sulfurane derivatives.

Axially chiral N,N′‐dioxides ethers for catalysis in enantioselective allylation of aldehydes

“…[1][2][3][4][5] Various chiral Lewis bases have received increasing attention in recent years, [6][7][8][9][10] which were employed in enantioselective allylation of aldehydes and ketones, such as binaphthyl-derivatives, 11 chiral phosphoramides, 12 chiral formamides, [13][14][15][16][17][18][19][20][21][22] ureas,, 23 diamine, 24 Ticomplexes, 25,26 Ir-complexes, [27][28][29] N,N′-dioxides, 19,30 and sulfoxides. [31][32][33][34][35] Among these compounds, bipyridine N,N ′-dioxides are particular groups that have been tested as potential catalysts for the allylation reaction of aldehydes. 36 Design and synthesis of novel chiral Lewis base catalysts have promoted the development of catalytic asymmetric allylations.…”

“…Chiral alcohols are indispensable for synthesis of pharmacological agents and other products; plenty of allylation methodologies have been developed over the last several decades using various chiral catalysts . Various chiral Lewis bases have received increasing attention in recent years, which were employed in enantioselective allylation of aldehydes and ketones, such as binaphthyl‐derivatives, chiral phosphoramides, chiral formamides, ureas,, diamine, Ti‐complexes, Ir‐complexes, N,N ′‐dioxides, and sulfoxides . Among these compounds, bipyridine N,N ′‐dioxides are particular groups that have been tested as potential catalysts for the allylation reaction of aldehydes .…”