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2S)-2-[(Phenylsulfinyl)methyl]pyrrolidine, derived from L-proline, has been demonstrated as an efficient organocatalyst for the asymmetric Michael addition of cyclohexanone and cyclopentanone to β-nitrostyrenes. This pyrrolidine-based catalyst bearing a sulfoxide moiety was used to synthesize various γ-nitro carbonyl compounds in high yield (up to 97%) with excellent stereoselectivity (up to >99:1 dr and >99% ee) without the use of any additive.Organocatalysis with its asymmetric variant has emerged as a powerful synthetic paradigm for the development of new methods to prepare diverse chiral molecules. 1 Organocatalytic conjugate addition is an important and widely applicable strategy for asymmetric carbon-carbon bond formation using a variety of donors and acceptors. 2 In recent years, several catalysts have been developed for the direct asymmetric Michael addition of unmodified carbonyl compounds to nitroalkenes to produce enantiomerically enriched γ-nitro ketones. 3 Many of these are pyrrolidine-based organocatalysts having different functionalities in the side chain. 4 Some examples of pyrrolidine-type organocatalysts bearing a sulfide/sulfone 5a or sulfonamide 5b function in the side chain have also been reported for the above reactions. An oxygen atom of the sulfone functionality in combination with a protic solvent, such as water, provides a hydrogen-bond interaction to improve both the reactivity and stereoselectivity of the Michael reaction. 5 β-Amino sulfoxides have been used as effective bidentate ligands in metal-catalyzed enantioselective reactions and have also served as chiral auxiliaries in various processes promoted by transition metals; 6 however, the use of β-amino sulfoxides as chiral organocatalysts does not seem to have been investigated so far. As part of our interest in the development of new pyrrolidinebased organocatalysts 7a and continuing our investigations toward the stabilization of α-amino sulfoxides, 7b we explored the use of β-amino sulfoxide 1 as a chiral catalyst in asymmetric Michael additions. Interestingly, this catalyst proved very successful for the stereoselective conjugate addition of cyclic ketones to various aryl-substituted nitroolefins and afforded the corresponding adducts in high yield (up to 97%) with excellent stereoselectivity (up to >99:1 dr and >99% ee) in wet toluene. The results are described in this paper. The chiral catalyst (2S)-2-[(phenylsulfinyl)methyl]pyrrolidine (1) employed in this work was easily prepared, according to Scheme 1. Reduction of Boc-protected Lproline 2 with borane-methyl sulfide complex (BMS) afforded the corresponding alcohol 3 in 92% yield. 8 Reaction of this alcohol 3 with p-toluenesulfonyl chloride 8 and subsequent treatment with sodium hydride and benzenethiol gave thioether 5. 5a Oxidation of 5 with sodium periodate in methanol-water (1:1) 9 and then deprotection 5a with trifluoroacetic acid furnished the catalyst 1 in 57% overall yield. Scheme 1 Synthesis of catalyst 1For initial studies, the reaction of cyclohexanone (7a) and β...

Focuses specifically on women’s multiple roles and how this can have a bearing on health and fitness. Looks at how effects of variable dynamics are crystallized in terms of coping strategies, counselling and other, related, research. Discusses various areas where women come under extra stress in multiple roles including: home life; ethnic and racial tensions at work; and various other negative stressors such as: maternal role vulnerability; work vulnerability; perceived quality of role demands and role conflict; influence of personal resources; and stress management. Finishes by listing out recommendations for clinical practice, policy implications and recommends directions for future research to aid in this area.

Catalytic asymmetric synthesis has become an essential tool for the enantioselective synthesis of pharmaceuticals, natural products, and agrochemicals (mainly fungicides, herbicides, insecticides, and pheromones). With continuous growing interest in both modern agricultural chemistry and catalytic asymmetric synthesis chemistry, this review provides a comprehensive overview of some earlier reports as well as the recent successful applications of various catalytic asymmetric syntheses methodologies, such as enantioselective hydroformylation, enantioselective hydrogenation, asymmetric Sharpless epoxidation and dihydroxylation, asymmetric cyclopropanation or isomerization, organocatalyzed asymmetric synthesis, and so forth, which have been used as key steps in the preparation of chiral agrochemicals (on R&D, piloting, and commercial scales). Chiral agrochemicals can also lead the new generation of such chemicals having specific and novel modes of action for achieving sustainable crop protection and production. Some perspectives and challenges for these catalytic asymmetric methodologies in the synthesis of chiral agrochemicals are also briefly discussed in the final section of the manuscript. This review will provide the insight regarding understanding, development, and evaluation of catalytic asymmetric systems for the synthesis of chiral agrochemicals among the agrochemists.

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