Carboxylate Assistance for Catalyzed Hydroarylations of Methylenecyclopropanes
摘要:
Carboxylate assistance enabled efficient and chemoselective ruthenium(II)-catalyzed hydroarylations and hydroalkenylations of highly strained methylenecyclopropanes via C-H bond activation occurring with ring conservation of the cyclopropane moieties.
We report here a C–H homoallylation reaction of aromaticketones with methylenecyclopropanes (MCPs) only using a catalytic amount of Fe(PMe3)4. A variety of aromaticketones and MCPs are applicable to the reaction to form ortho-homoallylated aromaticketones selectively via regioselective scission of the three-membered rings. The homoallylated products are amenable to further elaborations, providing
Cyclopropenylcarbinol Derivatives as New Versatile Intermediates in Organic Synthesis: Application to the Formation of Enantiomerically Pure Alkylidenecyclopropane Derivatives
作者:Samah Simaan、Ahmad Masarwa、Elinor Zohar、Amnon Stanger、Philippe Bertus、Ilan Marek
DOI:10.1002/chem.200901074
日期:2009.8.24
The copper‐catalyzed carbomagnesiation (or hydrometalation) reaction of chiralcyclopropenylcarbinolderivatives, obtained by means of a kinetic resolution of secondary allylic alcohols, leads to an easy and straightforward preparation of enantiomericallypurealkylidenecyclopropanederivatives. The reaction mechanism is composed of a syn‐carbometalation followed by a syn‐elimination reaction. To gain
Partial asymmetric synthesis of methylenecyclopropanes and spiropentanes
作者:R. Noyori、H. Takaya、Y. Nakanisi、H. Nozaki
DOI:10.1139/v69-202
日期:1969.4.1
Reaction of substituted allenes and diazomethane gives rise to optically active methylenecyclopropane and spiropentane derivatives in the presence of dissymmetric copper chelates, bis[N-(R and S)-α-phenethylsalicylaldiminato]copper(II).
NHC/Nickel(II)‐Catalyzed [3+2] Cross‐Dimerization of Unactivated Olefins and Methylenecyclopropanes
作者:Jian‐Qiang Huang、Chun‐Yu Ho
DOI:10.1002/anie.201914542
日期:2020.3.23
typical hydroalkenylation reactivity was observed for the first time by using a [NHC-Ni(allyl)]BArF catalyst (NHC=N-heterocyclic carbene). Results show that the C-C cleavage of 1 did not involve a Ni0 oxidative addition, which was crucial in former systems. Thus the method reported here emerges as a complementary method for attaining highly chemo- and regioselectivesynthesis of methylenecyclopentanes
the silyl compounds with a (2,2-diphenylcyclopropyl)methyl substituent in moderate to high yields without ring-opening of the substrate. PtI(2)(PPh(3))(2) is converted by the reaction into PtH(I)(PPh(3))(2), which also catalyzes the hydrosilylation of the methylenecyclopropanes. The reaction of 2-phenyl-1-methylenecyclopropane, 2-methyl-2-phenyl-1-methylenecyclopropane, 2,2-diphenethyl-1-methylenecyclopropane