Stereodivergent Synthesis of Functionalized Tetrahydropyrans Accelerated by Mechanism-Based Allylboration and
Lin Yang1, Zuming Lin1, Sha-Hua Huang2,3
1CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry (CAS), 345 Lingling Road, Shanghai, 200032, China.
Abstract:
A stereodivergent strategy enabled by bioinspired oxa-Michael cyclization was developed for the synthesis of functionalized tetrahydropyrans on the basis of the inherent symmetry in 1,3-diols, the symmetries of which were tunable by stereoselective hydroboration of an allene with a variety of alkylborane reagents and subsequent allylation of an aldehyde. The mechanism-based utilization of monoalkyl borane in the hydroboration and allylation cascade is unprecedented.
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