从容易获得的α,β-环氧酮制备了一系列迄今未知的3,4-环氧-1,1-二氟丁烯,发现这些化合物发生了区域选择性S N 2'反应,并在高度阳性时与硬RLi亲核试剂发生反应。与仅具有低区域选择性的相应非氟化乙烯基氧杂环戊烷的情况形成鲜明对比的是,带电末端具有氟的sp 2碳原子形成鲜明的对比。HMPA的加入大大改善了产物的烯属立体选择性。理论计算被用来定性地探索这些反应中选择性的性质。
从容易获得的α,β-环氧酮制备了一系列迄今未知的3,4-环氧-1,1-二氟丁烯,发现这些化合物发生了区域选择性S N 2'反应,并在高度阳性时与硬RLi亲核试剂发生反应。与仅具有低区域选择性的相应非氟化乙烯基氧杂环戊烷的情况形成鲜明对比的是,带电末端具有氟的sp 2碳原子形成鲜明的对比。HMPA的加入大大改善了产物的烯属立体选择性。理论计算被用来定性地探索这些反应中选择性的性质。
3-Silyloxytetrahydrofurans via sulfoxonium ylide reactions with α-silyloxyepoxides
作者:Paul S. Sabila、Yanke Liang、Amy R. Howell
DOI:10.1016/j.tetlet.2007.09.113
日期:2007.11
alpha-Silyloxyepoxides were found to undergo sulfoxonium ylide induced ring-opening, followed by silyl-migration and intramolecular S(N)2 reaction, resulting in 3-silyloxytetrahydrofurans. Studies on the scope and utility of this transformation are described. (C) 2007 Elsevier Ltd. All rights reserved.
2-Alkylidene oxetanes by stereospecific elimination of mesylates
作者:Paul S. Sabila、Amy R. Howell
DOI:10.1016/j.tetlet.2007.09.109
日期:2007.11
alpha-Mesyloxyoxetanes undergo stereospecific elimination to 2-alkylidene oxetanes upon treatment with potassium t-butoxide. (C) 2007 Elsevier Ltd. All rights reserved.
Preparation and Regioselective S<sub>N</sub>2‘ Reaction of Novel <i>g</i><i>em</i>-Difluorinated Vinyloxiranes with RLi
β-epoxy ketones and these compounds were found to undergo regioselective SN2‘ reactions with hard RLi nucleophiles occurring at the highly positively charged terminal fluorine-possessing sp2 carbon atom in quite sharp contrast to the cases of the corresponding nonfluorinated vinyloxiranes which only attained a low level of regioselectivity. Addition of HMPA substantially improved the products' olefinic
从容易获得的α,β-环氧酮制备了一系列迄今未知的3,4-环氧-1,1-二氟丁烯,发现这些化合物发生了区域选择性S N 2'反应,并在高度阳性时与硬RLi亲核试剂发生反应。与仅具有低区域选择性的相应非氟化乙烯基氧杂环戊烷的情况形成鲜明对比的是,带电末端具有氟的sp 2碳原子形成鲜明的对比。HMPA的加入大大改善了产物的烯属立体选择性。理论计算被用来定性地探索这些反应中选择性的性质。
Chakraborty; Mandal; Roy, Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 2015, vol. 54B, # 7, p. 893 - 901