Jie M S, Wong C F
Department of Chemistry, University of Hong Kong.
Lipids. 1992 Jan;27(1):59-64. doi: 10.1007/BF02537061.
Methyl oleate (18:1) and linoleate (18:2) were readily transformed to the corresponding gem-dichlorocyclopropane derivatives in high yield, using triethylbenzylammonium chloride as the phase-transfer catalyst in the presence of aqueous NaOH and CHCl3. Reaction of dichlorocarbene with methyl 12-hydroxystearate furnished methyl 12-chlorostearate (49%) and 12-O-formylstearate (19%). The hydroxy group in methyl ricinoleate was protected (O-tetrahydropyran-2'-yl) prior to dichlorocyclopropanation of the ethylenic bond. Removal of the protecting group allowed the hydroxy group to be converted to a chloride, O-acetyl, azido or O-formyl function. Treatment of methyl ricinoleate with thionyl chloride, followed by the reaction with dichlorocarbene gave the corresponding 12-chloro-dichlorocyclopropane derivative. The dichlorocyclopropane derivative of oleic acid was transformed to a C19 allenic fatty acid when treated with t-butyl lithium. However, the remaining dichlorocyclopropane derivatives containing an additional functional group in the alkyl chain, failed to yield the corresponding allenic derivatives. All derivatives were characterized by a combination of spectroscopic and chromatographic techniques, including infrared, 1H nuclear magnetic resonance (NMR), and 13C NMR spectroscopy.
在氢氧化钠水溶液和三氯甲烷存在的情况下，以三乙基苄基氯化铵作为相转移催化剂，油酸甲酯（18:1）和亚油酸甲酯（18:2）很容易高产率地转化为相应的偕二氯环丙烷衍生物。二氯卡宾与12-羟基硬脂酸甲酯反应生成12-氯硬脂酸甲酯（49%）和12-O-甲酰基硬脂酸甲酯（19%）。在对蓖麻油酸甲酯的烯键进行二氯环丙烷化反应之前，其羟基先被保护（O-四氢吡喃-2'-基）。去除保护基后，羟基可转化为氯、O-乙酰基、叠氮基或O-甲酰基官能团。用亚硫酰氯处理蓖麻油酸甲酯，然后与二氯卡宾反应，得到相应的12-氯-二氯环丙烷衍生物。油酸的二氯环丙烷衍生物用叔丁基锂处理时会转化为C19丙二烯脂肪酸。然而，在烷基链中含有额外官能团的其余二氯环丙烷衍生物未能生成相应的丙二烯衍生物。所有衍生物均通过光谱和色谱技术相结合的方法进行表征，包括红外光谱、1H核磁共振（NMR）和13C NMR光谱。
