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Accounts on the recent (over the past 10 years) catalytic asymmetric hydrogenation reaction‐based achievements with different catalysts to generate natural products and synthetic targets such as fragrances, pharmaceutical agents, and agrochemicals are mentioned in this present concise review. Mechanistic steps, chemoselectivity with higher functional group tolerance by employing transition metal‐based chiral catalysts (Ir‐, Rh‐, Ni‐, Ru‐, Fe‐, Mn‐, Pd‐, Co‐, and Zn‐based organometallic chiral complexes), and biocatalysts and their importance on the genesis of chirality coupled with higher turnover numbers are also described.

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Regioselective monotosylation, for the first time on 2,4-syn & 2,4-anti configured ene-tetrols and on diols & triols was achieved in excellent yields and selectivity by employing [DMAPTs] + Cl À , 1. We also proposed and developed operational flexible preferential regio-complimentary tosylation of cis-1,2-diol moiety of pyranosides by employing 1. Further NMR correlation for unambiguous structure determination of regioselectivity and also preferred conformations of these pyranosides were established.

N-benzoyl-4-dimethylaminopyridinium chloride [DMAPBz] + Cl À was efficiently employed for polybenzoylation of triols and tetrols without epimerization and elimination products. This Lewis base adduct has also been employed for regioselective monobenzoylation of polyols obtained from D-pentoses. Fur-ther an eco-friendly monobenzoylation of phenols, amines and alcohols was achieved in water as a solvent without using a base and chromatographic purification of the products. Chemoselective monobenzoylation and recovery of the DMAP is an added advantage of our protocol.