Effect of Chiral Diene Ligands in Rhodium-Catalyzed Asymmetric Addition of Arylboronic Acids to α,β-Unsaturated Sulfonyl Compounds

Abstract

Asymmetric addition of arylboronic acids to α,β-unsaturated sulfonyl compounds proceeded in the presence of a rhodium catalyst coordinated with a chiral diene ligand to give high yields of the addition products with high enantioselectivity (96->99.5% ee). The diene ligand was proved to be essential for the formation of the addition products, while the use of a bisphosphine ligand mainly gave the cine-substitution product.

Styrylsulfonates and ‐Sulfonamides through Pd‐Catalysed Matsuda–Heck Reactions of Vinylsulfonic Acid Derivatives and Arenediazonium Salts

“…One of the previously reported syntheses, of 2‐arylhomotaurines exploits the Michael‐acceptor reactivity of styrylsulfonates, which undergo conjugate addition of deprotonated nitromethane, followed by reduction of the nitro group to give a primary amine . Considerable efforts have been made over the past decade to render similar conjugate additions of nucleophiles to α,β‐unsaturated sulfones and sulfonic acid derivatives enantioselective . In Scheme , representative examples of synthetic transformations of vinylsulfonyl derivatives in general, and styrylsulfonyl derivatives in particular, are shown.…”

A chiral bicyclo[2.2.2]octa-2,5-diene ligand substituted with the ferrocenyl group and its use for rhodium-catalyzed asymmetric 1,4-addition reactions

“…For comparison, this table also contains the results of reactions in the presence of other related chiral diene/rhodium complexes, which have been previously reported as effective catalysts for the asymmetric 1,4-addition. The higher enantioselectivity of Fc,Ph-bod than Ph-bod was also observed in the reaction of enone 3b with phenylboronic acids substituted with 4-methoxy 4o, 4-chloro 4p, and 4-methoxycarbonyl 4q groups (entries [13][14][15][16][17][18]. 1 Thus, the reaction of 2-cyclohexenone 3a with phenylboronic acid 4m (2 equiv.)…”

“…[10][11][12][13][14][15] Typically, they are asymmetric additions of organoboron reagents to unsaturated compounds, such as aldehydes, 10a imines, 11 β-alkoxyacrylates, 12 α,β-unsaturated sulfonyl compounds, 13 and enynamides. [10][11][12][13][14][15] Typically, they are asymmetric additions of organoboron reagents to unsaturated compounds, such as aldehydes, 10a imines, 11 β-alkoxyacrylates, 12 α,β-unsaturated sulfonyl compounds, 13 and enynamides.…”

Rh-catalyzed asymmetric 1,4-addition reactions to α,β-unsaturated carbonyl and related compounds: an update

“…234 Based on the results of these 1,4-additions and the characterization of Rh/(S)-L62a complex by single crystal X-ray crystallography, a stereoselective route was suggested for the 1,4-addition of phenylboronic acid to 2-cyclohexenone under Rh/(S)-L62a catalysis as illustrated in Figure 12a. [235][236][237][238][239][240][241] As shown, the phenylrhodium species had a trans-relationship between the phenyl group and the olefin ligand, while 2-cyclohexenone binds to the rhodium with its si-face at the cis-position of the olefin ligand, resulting in the formation of the 1,4-adduct with an (S)-configuration. The generation of the (R)-product utilizing Rh/(S)-L62d can be explained similarly by the re-face coordination of 2-cyclohexenone to rhodium as depicted in Figure 12b (Tables 74-76).…”