A New Type of Chiral Cyclic Sulfinamide–Olefin Ligands for Rhodium‐Catalyzed Asymmetric Addition

Abstract

A new type of chiral cyclic sulfinamide–olefin ligands, N‐allylic 2,3‐dihydro‐1,2‐benzoisothiazole 1‐oxides, with 2,3‐dihydro‐1,2‐benzoisothiazole 1‐oxide as a unique chiral skeleton, is developed for the highly enantioselective rhodium‐catalyzed asymmetric 1,4‐addition of α,β‐unsaturated cyclic carbonyl compounds and the 1,2‐addition of benzil. Both enantiomers of the chiral cyclic sulfinamide–olefin ligand with 99 % ee were easily prepared from inexpensive and commercially available starting materials and were directly used in asymmetric catalysis, and thus, both enantiomers of the addition products could be obtained in high yields (up to 98 %) with excellent enantioselectivities (up to 98 % ee).

Copper‐Catalyzed C−S Coupling of Quaternary Ammonium Salts and Dialkylcarbamodithioic Acid Salts

“…As dialkylcarbamodithioic acid salts are readily available, stable, nonvolatile, and safe, they might be suitable C−S coupling substrates, but have yet to adopt in C−S coupling. As part of our ongoing study on chiral organosulfur chemistry and cross‐coupling reactions, in this study, we have explored the Cu‐catalyzed C−S cross coupling of (chiral) quaternary ammonium salts and (chiral) dithiocarbamic acid salts, which is an efficient method for the synthesis of (chiral) alkyl dialkylcarbamodithioates.…”

Ru-Catalyzed Asymmetric Addition of Arylboronic Acids to Aliphatic Aldehydes via P-Chiral Monophosphorous Ligands

“…For example, metals including Rh [40][41][42][43][44][45][46][47][48], Ru [49], Ni [50], Co [51] and Pd [52][53][54] have been intensively explored in this regard recently. Additionally, miscellaneous carbonyl compounds, such as asisatins [55][56][57][58], ketoesters [59][60][61][62][63], diketones [64][65][66], trifluoroacetophenones [67][68][69], inactive ketones [70][71][72] and aldehydes [73][74][75] were successfully employed to couple with organoborons reagents.…”

“…Despite the fact that these remarkable achievements were created in the asymmetric addition of carbonyl compounds with organoboron reagents, efforts have been mainly devoted to the active ketones [55][56][57][58][59][60][61][62][63][64][65][66][67][68][69], inactive ketones [70][71][72], and aromatic aldehydes [73][74][75],…”

Chiral N-aryl tert-butanesulfinamide-olefin ligands for rhodium-catalyzed asymmetric 1,4-addition of aryl boronic acids to cyclic enones

“…11 Recently chiral sulfoxide-and sulfinamide-olefins are developing as new types of chiral ligands. [12][13] Knochel, 14 Xu, [15][16][17] Du, [18][19] Liao, [20][21] Wan, 22 Chen, 23 Zeng 24 and so on have developed a series of chiral sulfoxide-olefin and sulfinamide-olefin ligands. Some typical chiral ligands are shown in Figure 1.…”

“…Our group has done a series of researches on chiral organic sulfur chemistry, [24][25][26][27] especially we have reported synthesis of a sulfinamide-olefin compound, namely, N-allyl-N-phenyl-tert-butanesulfinamide, via C-N coupling reaction and SN2 nucleophilic substitution. 28 As we know, sulfinamide-olefin compounds are recently used as chiral ligand in highly enantioselective rhodium-catalyzed asymmetric 1,4-addition reaction of arylboronic acids to ,-unsaturated carbonyl compounds, [29][30] which has extensive applications in medicinal synthesis and natural synthesis, 31 and has achieved great progress.…”