A Modular Synthesis of 2-Alkyl- and 2-Arylchromans via a Three-Step Sequence

Abstract

A convergent three-step method for the synthesis of 2-substituted chromans is described. These results have been accomplished via the Heck coupling of readily accessible allylic alcohols and 2-iodophenols, followed by reduction and Mitsunobu cyclization. The utility and generality of this method is demonstrated through the synthesis of a series of 2-aryl-, 2-heteroaryl- and 2-alkylchromans, as well as an azachroman derivative. The asymmetric version of this approach via a Noyori-catalyzed ketone reduction and subsequent cyclization is likewise highlighted.

Key words

asymmetric synthesis - chromans - catalysis - Heck reaction - Mitsunobu reaction - heterocycles

• References

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