Base-Induced Solvolyses of [3.2.1]Bicyclic α,α′-Dichloro Ketones − 1,3-Transposition and Ring-Contraction
作者:Baldur Föhlisch、Andreas Radl、Rüdiger Schwetzler-Raschke、Sonja Henkel
DOI:10.1002/1099-0690(200111)2001:22<4357::aid-ejoc4357>3.0.co;2-o
日期:2001.11
α-oxo-acetals (3b, 5b, 17, 18) through an enolization/ionization mechanism. With trifluoroethanol/sodium trifluoroethoxide, the corresponding trifluoroethyl acetals (3a and 5a) are formed. Basic hydrolysis affords 2-endo-hydroxynorbornene-2-exo-carboxylic acid (20x) and the 7-oxa analogues (22x, 23x), presumably through benzilic acid rearrangement of the α-diketones.
2,4-二氯双环[3.2.1]oct-6-en-3-one (1) 及其螺环丙烷 (4) 和 8-oxa 类似物 (15, 16) 与甲醇甲醇钠反应生成双环 α-oxo-缩醛 (3b, 5b, 17, 18) 通过烯醇化/电离机制。使用三氟乙醇/三氟乙醇钠,形成相应的三氟乙基缩醛(3a 和 5a)。碱性水解产生 2-endo-hydroxynorbornene-2-exo-羧酸 (20x) 和 7-oxa 类似物 (22x, 23x),大概是通过 α-二酮的苯甲酸重排。