Nickel-catalyzed allylic defluorinative alkylation of trifluoromethyl alkenes with reductive decarboxylation of redox-active esters
作者:Xi Lu、Xiao-Xu Wang、Tian-Jun Gong、Jing-Jing Pi、Shi-Jiang He、Yao Fu
DOI:10.1039/c8sc04335c
日期:——
Herein, we report a nickel-catalyzed allylic defluorinative alkylation of trifluoromethyl alkenes throughreductive decarboxylation of redox-active esters. The present reaction enables the preparation of functionalized gem-difluoroalkenes with the formation of sterically hindered C(sp3)–C(sp3) bonds under very mild reaction conditions, while tolerating many sensitive functional groups and requiring
Construction of fully substituted carbon centers containing a heteroatom and a CF<sub>3</sub> group <i>via in situ</i> generated <i>p</i>-quinone methides
p-quinone methides have been achieved with a variety of heteronucleophiles undermildconditions, which led to facile and practical construction of fully substituted carbon centers including a heteroatom and a CF3 group. In particular, it was revealed that some amines themselves worked for efficient cleavage of the TBS protective group, and addition of a catalytic amount of an appropriate Brønsted acid was
construction of quaternary centers with a trifluoromethyl group was realized by way of 1,6-addition of various nucleophiles including active methylene compounds to highly reactive δ-trifluoromethylated p-quinone methides generated in situ from the corresponding tertiary carbonates with a catalytic amount of an appropriate base.
A Chiral Pentafluorinated Isopropyl Group via Iodine(I)/(III) Catalysis
作者:Stephanie Meyer、Joel Häfliger、Michael Schäfer、John J. Molloy、Constantin G. Daniliuc、Ryan Gilmour
DOI:10.1002/anie.202015946
日期:2021.3.15
catalysis strategy to construct an enantioenriched fluorinated isostere of the iPr group is reported. The difluorination of readily accessible α‐CF3‐styrenes is enabled by the in situ generation of a chiral ArIF2 species to forge a stereocentre with the substituents F, CH2F and CF3 (up to 95 %, >20:1 vicinal:geminal difluorination). The replacement of the metabolically labile benzylic proton results
报道了构建 Pr 基团的对映体富集氟化等排体的 I(I)/(III) 催化策略。通过原位生成手性 ArIF 2物质,可实现易于接近的 α-CF 3 -苯乙烯的二氟化,从而与取代基 F、CH 2 F 和 CF 3形成立构中心(高达 95 %,>20:1邻位) :偕二氟化)。通过X射线晶体学(π→σ*和立体电子gauche σ→σ*相互作用)确定,代谢不稳定的苄基质子的替代产生了高度预组织的支架。公开了一种催化剂编辑方法,其中对映选择性的初步验证是建立在结构基础上的。
Defluorinative C–C Bond-Forming Reaction of Trifluoromethyl Alkenes with <i>gem</i>-(Diborylalkyl)lithiums
作者:Haeun Kim、Yujin Jung、Seung Hwan Cho
DOI:10.1021/acs.orglett.2c00809
日期:2022.4.15
We report the transition-metal-free defluorinative C–C bond-forming reaction of trifluoromethyl alkenes with gem-(diborylalkyl)lithiums. This synthetic strategy provides access to a variety of 4,4-difluoro homoallylic diboronate esters, which serve as versatileintermediates in the efficient preparation of valuable gem-difluoroalkene derivatives. Further synthetic modifications are conducted to demonstrate