General Cyclopropane Assembly via Enantioselective Transfer of a Redox‐Active Carbene to Aliphatic Olefins

Asymmetric cyclopropane synthesis currently requires bespoke strategies, methods, substrates and reagents, even when targeting similar compounds. This slows down discovery and limits its available chemical space. Here we introduce a practical and versatile diazocompound, and we demonstrate its performance in the first unified asymmetric synthesis of functionalized cyclopropanes. We found that the redox‐active leaving group in this reagent enhances the reactivity and selectivity of geminal carbene transfer. This effect allowed for the asymmetric cyclopropanation of various olefins including unfunctionalized aliphatic alkenes, that enables the 3‐step total synthesis of (–)‐dictyopterene A. This unified synthetic approach delivers high enantioselectivities that are independent of the stereoelectronic properties of the functional groups transferred. Our results demonstrate that orthogonally‐differentiated diazocompounds are viable and advantageous equivalents of single‐carbon chirons.

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