Dioxolane derivatives for use as chemical intermediates
申请人:IMPERIAL CHEMICAL INDUSTRIES PLC
公开号:EP0037697A1
公开(公告)日:1981-10-14
The invention is concerned with novel dioxolane derivatives of the formula:-
in which Ra is hydrogen or (1-4C)alkyl and Rb is (1-4C)alkyl or phenyl optionally bearing a halogeno substituent; their production; and their use for the manufacture of certain known anti-arthritic acids of the formula:-
and, in particular, those acids in which Ra=Rb=methyl or Ra=ethyl and Rb =phenyl, by a novel reduction process. The preferred reduction procedures involve the use of an alkali metal borohydride or cyanoborohydride in the presence of a noble metal catalyst, or the use of an α-branched alkyl or cycloalkyl Grignard agent.
The use of the derivatives of formula avoids the need for potentially toxic reagents and reactive intermediates in the previously known processes for the production of the acids of formula V.
本发明涉及式如下的新型二氧戊环衍生物
其中Ra为氢或(1-4C)烷基,Rb为(1-4C)烷基或任选带有卤代基的苯基;它们的生产;以及它们用于制造某些已知的式为:-的抗关节炎酸。
特别是Ra=Rb=甲基或Ra=乙基和Rb=苯基的那些酸,采用新的还原工艺。优选的还原过程包括在贵金属催化剂存在下使用碱金属硼氢化物或氰基硼氢化物,或使用 α-支链烷基或环烷基格氏剂。
使用式的衍生物可以避免在以前已知的生产式 V 酸的工艺中使用可能有毒的试剂和反应中间体。
Lewis acid-mediated mono- and bis-addition of C -nucleophiles to 1,3-dioxolan-4-ones
作者:Vitaly A. Shcherbinin、Valery V. Konshin
DOI:10.1016/j.tetlet.2018.06.060
日期:2018.8
The reactions of 1,3-dioxolan-4-ones, readily available from a-hydroxy acids and aldehydes, with C-nucleophiles are described. Two possible reaction pathways resulting in O-substituted acids and tri-(hetero)arylmethanes are shown. (C) 2018 Elsevier Ltd. All rights reserved.
Halogenated carbonyl ylides in the reactions of mercurial dihalocarbene precursors with substituted benzaldehydes
作者:Charles W. Martin、Paul R. Lund、Erich Rapp、John A. Landgrebe
DOI:10.1021/jo00400a009
日期:1978.3
Pette, Recueil des Travaux Chimiques des Pays-Bas, 1934, vol. 53, p. 967,977