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Updated: Sep 21, 2025
Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Enzymatic Enantioselective anti-Markovnikov Hydration of Aryl Alkenes
Hui Lin1, Yinyin Meng1, Na Li2
1College of Life Sciences, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China.
Abstract:
The addition of water to alkenes is an important method for the synthesis of alcohols, but the regioselectivity of acid-catalyzed hydration of terminal alkenes yields secondary alcohols according to Markovnikov's rule, making it difficult to obtain primary alcohols. Here we report a styrene monooxygenase that catalyzes the anti-Markovnikov hydration of the terminal aryl alkenes under anaerobic conditions. This hydration provides primary alcohols in good yields (up to 100 %), excellent anti-Markovnikov regioselectivity (>99 : 1), and good enantiomeric purity (60-83 % ee). Residues Asn46, Asp100, and Asn309 are essential for catalysis suggesting an acid-base mechanism with a carbanion-like intermediate that could account for the anti-Markovnikov regioselectivity. Our work reveals a new enzymatic tool with unusual regioselectivity based on the promiscuous catalytic activity of a monooxygenase.
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