THE SYNTHESES OF POTASSIUM SELENOCARBOXYLATES AND THEIR DERIVATIVES
作者:Hideharu Ishihara、Yoshio Hirabayashi
DOI:10.1246/cl.1976.203
日期:1976.3.5
Potassium selenocarboxylates were prepared in good yields on the reaction of diacyl selenides with methanolic potassium hydroxide. They were fairly stable under nitrogen and useful as starting material for the preparation of selenocarboxylic acid derivatives; methyl selenobenzoate, α-(selenobenzoyl)acetophenone, phenyl p-chlorobenzoyl diselenide, O-trimethylsilyl selenobenzoate, bis(selenostearoyl)methane, and dibenzoyl diselenide.
An unprecedented transfer of selenium ion from potassium selenocyanate was observed in C-Se cross-coupling reaction catalyzed by copper oxide nanoparticles under ligand-free conditions. Utilizing this protocol wide range of symmetrical diaryl selenides were obtained in excellent yields. Nano-CuO is recyclable up to four cycles without loss of catalytic activity.
Various diacyl selenides, diacyl diselenides and selenocarboxylates were synthesized by reaction of several acyl chlorides with LiAlHSeH. Reaction of diacyl chloride with LiAlHSeH afforded cyclic selenoanhydrides. In the 77Se NMR spectra, we found that the chemical shifts of the diacyl selenides and the diacyl diselenides could facilitate their distinction.
Diacyl selenides were synthesized in good yields by the deselenization of diacyl diselenides, which have conveniently been prepared from acyl chlorides and sodium hydroselenide. The reaction of dibenzoyl selenide with piperidine at 0 °C formed a fairly stable piperidinium salt. The methanolysis of distearoyl selenide gave selenostearic acid as an unstable intermediate.
通过对二酰基二硒化物进行脱硒合成了二酰基硒化物,而二酰基二硒化物是从酰基氯和氢硒化钠中方便地制备出来的。二苯甲酰基硒化物与哌啶在 0 °C 下反应生成了相当稳定的哌啶盐。二硬脂酰硒化物的甲醇分解产生的硒硬脂酸是一种不稳定的中间体。
Organoselenosilane-Mediated Selective Mild Access to Selenolesters, Selenoanhydrides and Diacyl Diselenides
Reaction of acylchlorides with phenylselenotrimethylsilane promoted by TBAF afforded a mildgeneral access to selenolesters in good yields. When acylchlorides were reacted with bis(trimethylsilyl)selenide (HMDSS) in 2:1 or 1:1 ratio a selective entry to selenoanhydrides or diacyl diselenides respectively was obtained.