Montmorillonite K 10 (clay) catalyzed hydrolysis of aryl-substituted α,β-difluoroallyl alcohols leading to (Z)-α-fluoro-β-aryl-substituted acrylaldehydes
摘要:
Aryl-substituted alpha,beta-difluoroallyl alcohols 1 were readily hydrolyzed in the presence of a catalytic amount of montmorillonite K 10 (clay) in hexane at reflux temperature for 1 h to give the corresponding (Z)-alpha-fluoro-beta-aryl-substituted acrylaldehydes 2 in good yields. (C) 1999 Elsevier Science Ltd. All rights reserved.
Reaction of β-fluorovinamidinium salt with Grignard reagents. Facile and efficient route to (Z)-α-fluoro-α,β-unsaturated aldehydes
作者:Hiroki Yamanaka、Yasumasa Odani、Takashi Ishihara、John T Gupton
DOI:10.1016/s0040-4039(98)01459-2
日期:1998.9
β-Fluorovinamidinium salt (1) reacted cleanly with a variety of Grignard reagents in tetrahydrofuran at room temperature, followed by acid workup, to produce the corresponding (Z)-α-fluoro-α,β-unsaturated aldehydes (3) in good to excellent yields.
An Efficient and General Entry to (<i>Z</i>)-<i>α</i>-Fluoro-<i>β</i>-substituted Acrylaldehydes Based on the Coupling Reaction of<i>α</i>-Fluoro-<i>β</i>-amino Acrylaldehydes with Organolithium Reagents
of polyfluoroalkenyl tosylates (1) with dialkylamines in the presence of triethylamine and a catalytic amount (10 mol%) of tetrabutylammonium fluoride (TBAF), reacted smoothly with various organolithiumreagents at −78 °C for 0.5 h, followed by hydrolysis with 10% hydrochloric acid at room temperature for 1 h to afford the corresponding (Z)-α-fluoro-β-substituted acrylaldehydes (3) via allylic rearrangement