Conversion between Difluorocarbene and Difluoromethylene Ylide
作者:Jian Zheng、Jin-Hong Lin、Ji Cai、Ji-Chang Xiao
DOI:10.1002/chem.201303248
日期:2013.11.4
The interconversion between difluoromethylene ylide and difluorocarbene is described. The difluoromethylene ylideprecursor, Ph3P+CF2CO2−, could be turned into an efficient difluorocarbene reagent, whereas the classical difluorocarbene reagents, HCF2Cl and FSO2CF2CO2TMS, could generate highly reactive difluoromethylene ylide. Thus the Wittig difluoro‐olefination and difluorocyclopropanation could be
描述了二氟亚甲基叶立德和二氟卡宾之间的相互转化。该二氟亚甲基叶立德前体中,Ph 3 P + CF 2 CO 2 - ,也可以变成一个高效的二氟卡宾的试剂,而经典二氟卡宾的试剂,HCF 2 Cl和FSO 2 CF 2 CO 2 TMS,可能会产生高反应性的二氟亚甲基内鎓盐。因此,使用相同的试剂可以选择性地实现Wittig的二氟烯烃化和二氟环丙烷化。另外,从不同卡宾来源获得的叶立德在维蒂希反应中显示出不同的反应性。
Ring-Opening Functionalization of Simple <i>gem</i>-Difluorocyclopropanes by Single-Electron Oxidants
reported for the first time that single-electron oxidants such as CAN or K2S2O8 affected facile ringopening of simple gem-difluorocyclopropanes to afford 1,3-dibromo-2,2-difluoropropanes in good yields by the action of KBr, and the appropriate choice of conditions allowed to incorporate not only second halogen atoms but also hydroxy or acetamido groups at the C1 position in the difluoropropane structures
首次报道,单电子氧化剂(例如CAN或K 2 S 2 O 8)通过简单的作用影响简单的宝石-二氟环丙烷的开环,从而通过该作用提供了高收率的1,3-二溴-2,2-二氟丙烷。在通过引入第一个溴原子开始反应后,以区域特异性的方式,适当地选择条件允许在位置上不仅允许在第二氟丙烷结构中并入第二卤原子,而且可以在二氟丙烷结构的C 1位上掺入羟基或乙酰氨基基团。 C 3位置。
Palladium-catalyzed allylic alkylation dearomatization of β-naphthols and indoles with <i>gem</i>-difluorinated cyclopropanes
作者:Zhiyuan Fu、Jianping Zhu、Songjin Guo、Aijun Lin
DOI:10.1039/d0cc07529a
日期:——
route to access 2-fluoroallylic β-naphthalenones and indolenines bearing quaternary carbon centers in good yields with high Z-selectivity via C–C bond activation, C–F bond cleavage and the dearomatization process, benefiting from the wide substrate scope and good functional group tolerance. Moreover, 2-fluoroallylic furanoindoline and pyrroloindolines were achieved in good efficiency via cascade allylic
Trimethylsilyl fluorosulfonyldifluoroacetate (TFDA): a new, highly efficient difluorocarbene reagent
作者:William R Dolbier、Feng Tian、Jian-Xin Duan、An-Rong Li、Samia Ait-Mohand、Olivia Bautista、Saiwan Buathong、J Marshall Baker、Jen Crawford、Pauline Anselme、Xiao Hong Cai、Aneta Modzelewska、Henryk Koroniak、Merle A Battiste、Qing-Yun Chen
DOI:10.1016/j.jfluchem.2003.12.002
日期:2004.3
TFDA is readily prepared from the reaction of fluorosulfonyldifluoroacetic acid with trimethylsilyl chloride, and it is a very effective and efficient source of difluorocarbene for use in addition reactions to alkenes of a broad scope of reactivities. Acid-sensitive substrates may require an additional purification step involving treatment of the distilled TFDA with sufficient Et3N to remove the acid
METHOD FOR PRODUCING DIFLUOROCYCLOPROPANE COMPOUND
申请人:Amii Hideki
公开号:US20120277458A1
公开(公告)日:2012-11-01
Provided is a method for producing a difluorocyclopropane compound under milder reaction conditions and with high selectivity and high yield. The method for producing a difluorocyclopropane compound of the present invention is characterized by using sodium bromodifluoroacetate as a difluorocyclopropanation agent. With the disclosed method, a difluorocyclopropane compound can be produced under milder reaction conditions and with a higher conversion rate and a higher yield compared to conventional art. Further, by-products can be reduced significantly, thus allowing waste to be greatly reduced. Accordingly, the production method of the present invention is easy to implement industrially (can be employed on an industrial scale) and is thus extremely practical and useful.