Carbene chemistry. Part X. Insertion reactions of 1,2,2-trifluoroethylidene into C–H bonds of alkanes containing the t-butyl group and some addition and insertion reactions of 2-chloro-1,2,2-trifluoroethylidene
作者:Robert N. Haszeldine、Colin R. Pool、Anthony E. Tipping、Richard O'B. Watts
DOI:10.1039/p19760000513
日期:——
(2-Chloro-1,1,2,2-tetrafluoroethyl)trifluorosilane is best prepared by fluorination of trichloro-(1,1,2,2-tetrafluoroethyl)silane followed by vapour-phase photochemical chlorination. On pyrolysis the silane affords 2-chloro-1,2,2-trifluoroethylidene, which inserts into the Si–H bond of trimethylsilane and reacts with allene to afford 1-chlorodifluoromethyl-1-fluoro-2-methylenecyclopropane. Stereospecific addition
1,2,2-三氟亚乙基,由三氟- (1,1,2,2-四氟乙基)的热解产生的硅烷,插入专门进烷烃我的叔C-H键2 CH·CME 3,到这两个主烷烃EtCMe 3中乙基的C和H二级键(比例1:2),以及烷烃Me 2中异丁基的叔C和H仲键(比例约8:1)CH·CH 2 ·CMe 3。(2-氯-1,1,2,2-四氟乙基)三氟硅烷的最佳制备方法是先对三氯-(1,1,2,2-四氟乙基)硅烷进行氟化,然后进行气相光化学氯化。在热解过程中,硅烷生成2-氯-1,2,2-三氟亚乙基,后者插入三甲基硅烷的Si-H键中并与丙二烯反应,生成1-氯二氟甲基-1-氟-2-亚甲基环丙烷。将卡宾立体定向加成到反式-丁-2-烯的双键上,得到r -1-氯二氟甲基-1-氟-c -2,t -3-二甲基环丙烷,但与顺式-but-2-反应烯不是立体定向的,并提供c -2,c -3-和t -2,t -3-二甲基环丙烷与c -2,t -3-二甲基环丙烷的比例为63:18。