An efficient copper-catalyzed radical ring-opening halogenation with HX (aq) is described. This protocol features redox-neutral conditions, green halogen sources, and a broad substrate scope, providing practical access to distally chlorinated, brominated and iodinated alkyl ketones and alkyl nitriles with moderate to good yields.
Visible light-promoted ring-opening functionalization of unstrained cycloalkanols<i>via</i>inert C–C bond scission
作者:Dongping Wang、Jincheng Mao、Chen Zhu
DOI:10.1039/c8sc01763h
日期:——
light-promoted ring-opening functionalization of unstrained cycloalkanols. Upon scission of an inert cyclic C–C σ-bond, a set of medium- and large-sizedrings are readily brominated under mild reaction conditions to afford the corresponding distal bromo-substituted alkyl ketones that are hard to synthesize otherwise. The products are versatile building blocks, which are easily converted to other valuable
Iron-Catalyzed Decarboxylative Olefination of Unstrained Carbon–Carbon Bonds Relying on Alkoxyl Radical Induced Cascade
作者:Pin Gao、Hao Wu、Jun-Cheng Yang、Li−Na Guo
DOI:10.1021/acs.orglett.9b02675
日期:2019.9.6
An iron-catalyzed decarboxylative olefination of unstrained carbon-carbon bonds via alkoxylradical induced C-C bond cleavage is presented. This protocol features mild conditions (room temperature, redox-neutral), good substrate scope and functional group compatibility, as well as excellent stereoselectivity, thus providing a facile access to the distal alkenyl ketones.
Stereochemistry of the thermal isomerizations of (1R,2R)-1-[(E)-styryl]-2-methylcyclopropane to 3-phenyl-4-methylcyclopentenes
作者:John E. Baldwin、Samuel Bonacorsi
DOI:10.1021/ja00076a021
日期:1993.11
(1R,2R)-1-((E)-Styryl)-2-methylcyclopropane at 250 o C racemizes and isomerizes to 6-phenylhexa-1,4-(Z)-diene and to the four isomers of 3-phenyl-4-methylcyclopentene. From the measured rate constants for racemization and for structural isomerizations, and from information on the relative amounts of the four 3-phenyl-4-methylcyclopentenes as a function of time, the relative contributions of the four
(1R,2R)-1-((E)-Styryl)-2-methylcyclopropane 在 250 o C 外消旋并异构化为 6-苯基六-1,4-(Z)-二烯和 3-苯基-的四种异构体4-甲基环戊烯。从外消旋化和结构异构化的测量速率常数,以及四种 3-苯基-4-甲基环戊烯的相对量随时间变化的信息,四种立体化学不同路径对这种乙烯基环丙烷重排的相对贡献是发现为 60% si、10% ar、19% sr 和 11% ai
Reaction of 1-chloro-2-alkylcycloalkenes with organolithium reagents. A novel cyclopropanation reaction involving the generation of carbenes from vinyl halides
作者:Paul G. Gassman、Joseph J. Valcho、Gary S. Proehl、Charles F. Cooper