Low-Temperature Reactions of α-Bromopropanoyl Chloride with Lithium Derivative of Ethyl Acetate
作者:Z. R. Valiullina、L. S. Khasanova、A. M. Galeeva、N. K. Selezneva、M. S. Miftakhov
DOI:10.1134/s1070428019110137
日期:2019.11
The reaction of 2-bromopropanoyl chloride with lithium ethyl acetate generated in situ by the reaction of equimolar amounts of lithium diisopropylamide with ethyl acetate forms, depending on the conditions (temperature, time, reagent ratio), diethyl 2,2′-(3-methyloxirane-2,2-diyl)diacetate, 2,2-dibromo-N,N-diisopropylpropanamide, and ethyl (5-methyl-4-oxo-4,5-dihydrofuran-2-yl)acetate as minor by-products
通过等摩尔量的二异丙基氨基锂与乙酸乙酯反应生成2-溴丙酰氯与就地生成的乙酸乙酯锂,具体取决于条件(温度,时间,试剂比),2,2'-(3-甲基环氧乙烷-2,2-二基)二乙酸酯,2,2-二溴-N,N-二异丙基丙酰胺和乙酸乙酯(5-甲基-4-氧代-4,5-二氢呋喃-2-基)乙酸酯为次要副产物用预期的酰化产物4-溴-3-氧戊酸乙酯。与2或5当量的乙酸乙酯锂(–78°C→–20°C)的反应,与上述α-溴酸酯一起提供乙基(5-甲基-4-氧代-4,5-二氢呋喃-2第二LiCH 2 CO 2的加合物转化形成的乙酸基-乙酸酯Et分子和4-溴-3-氧代戊酸乙酯。2-溴丙酰氯与丙二酸钠的反应涉及主要预期的酰化产物的烯醇形式的酰化,得到| 2-溴-1-[[(2-溴丙酰基)氧基]亚丙基-丙二酸二甲酯。