Aldol Reactions of α-Bromoalkyl Phenyl Ketones and Aldehydes with Tin(IV) Iodide and Tetrabutylammonium Iodide

Abstract

Aldol reactions of α-bromoacetophenone and aldehydes in dichloromethane produced the corresponding E-α,β-unsaturated ketones at 25 °C with one equimolar amount of tin(IV) iodide, one equimolar amount of tetrabutylammonium iodide and one equimolar amount of N,N-diisopropylethylamine, and produced the corresponding β-hydroxy ketones at -80 °C with one equimolar amount of tin(IV) iodide and two equimolar amounts of tetrabutylammonium iodide. Using one equimolar amount of tin(IV) iodide and two equimolar amounts of tetrabutylammonium iodide at -80 °C in dichloromethane, α-bromopropiophenone reacted with aldehydes to afford the corresponding syn-α-methyl-β-hydroxy ketones selectively.

Key words

aldol reactions - diastereoselectivity - tin - enones - β-hydroxyketones

References and Notes

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