Diastereo-Divergent Synthesis of Saturated Azaheterocycles Enabled by tBuOK-Mediated Hydroamination of Alkenyl Hydrazones.

Chemistry

Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371 (Singapore).

Published: December 2015

Diastereo-divergent synthesis of saturated azaheterocycles has been achieved by tBuOK-mediated hydroamination of alkenyl hydrazones. DFT calculations suggested that the cation-π interactions between a potassium cation and aryl substituents on hydrazones give rise to 2,5-cis selectivity in pyrrolidines, which were synthesized by the reaction of γ,δ-unsaturated N-benzyl hydrazones. By contrast, 2,5-trans selectivity was observed when an isopropyl group was used as the substituent on hydrazones. An unusual 2,6-trans selectivity in piperidine formation was also realized using the present strategy.

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http://dx.doi.org/10.1002/chem.201504160DOI Listing

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Diastereo-Divergent Synthesis of Saturated Azaheterocycles Enabled by tBuOK-Mediated Hydroamination of Alkenyl Hydrazones.

Chemistry

December 2015

Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371 (Singapore).

Diastereo-divergent synthesis of saturated azaheterocycles has been achieved by tBuOK-mediated hydroamination of alkenyl hydrazones. DFT calculations suggested that the cation-π interactions between a potassium cation and aryl substituents on hydrazones give rise to 2,5-cis selectivity in pyrrolidines, which were synthesized by the reaction of γ,δ-unsaturated N-benzyl hydrazones. By contrast, 2,5-trans selectivity was observed when an isopropyl group was used as the substituent on hydrazones.

View Article and Find Full Text PDF

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