Direct Access to 2,3,4,6-Tetrasubstituted Tetrahydro-2H-pyrans via Tandem S2'-Prins Cyclization.

Org Lett

Instituto de Productos Naturales y Agrobiología, CSIC , Francisco Sánchez 3, 38206 La Laguna, Tenerife, Spain.

Published: September 2017

A new, direct, and diastereoselective synthesis of activated 2,3,4,6-tetrasubstituted tetrahydro-2H-pyrans is described. In this reaction, iron(III) catalyzed an S2'-Prins cyclization tandem process leading to the creation of three new stereocenters in one single step. These activated tetrahydro-2H-pyran units are easily derivatizable through CuAAC conjugations in order to generate multifunctionalized complex molecules. DFT calculations support the in situ S2' reaction as a preliminary step in the Prins cyclization.

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http://dx.doi.org/10.1021/acs.orglett.7b02270DOI Listing

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Direct Access to 2,3,4,6-Tetrasubstituted Tetrahydro-2H-pyrans via Tandem S2'-Prins Cyclization.

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September 2017

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A new, direct, and diastereoselective synthesis of activated 2,3,4,6-tetrasubstituted tetrahydro-2H-pyrans is described. In this reaction, iron(III) catalyzed an S2'-Prins cyclization tandem process leading to the creation of three new stereocenters in one single step. These activated tetrahydro-2H-pyran units are easily derivatizable through CuAAC conjugations in order to generate multifunctionalized complex molecules.

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