Synthesis and electronic effect of the substituents on anionic ring-opening polymerization of para-substituted phenyl cyclopropanes
作者:Jin-Bong Kim、Iwhan Cho
DOI:10.1016/s0040-4020(97)00954-x
日期:1997.11
resulting polymers. The rate constants of polymerization(kp) in DMSO by 2 mole% cyanide ion at 35°C were p-MeO=0.45, p-Me=0.14, p-H=0.07, p-Cl=0.06 and p-NO2=0.011 liter/mole.sec, and the rate constants of polymerization in DMSO by 5 mole% pyridine at 35°C were p-Me0=0.048, p-Cl=7.6 × 10−3 and , respectively. The electronic effect exerted by substituents were well consistent with the Hammett relationship(log
Ring Opening of Donor-Acceptor Cyclopropanes with the Azide Ion: A Tool for Construction of N-Heterocycles
作者:Konstantin L. Ivanov、Elena V. Villemson、Ekaterina M. Budynina、Olga A. Ivanova、Igor V. Trushkov、Mikhail Ya. Melnikov
DOI:10.1002/chem.201405551
日期:2015.3.23
general method for ringopening of various donor–acceptor cyclopropanes with the azide ion through an SN2‐like reaction has been developed. This highly regioselective and stereospecific process proceeds through nucleophilic attack on the more‐substituted C2 atom of a cyclopropane with complete inversion of configuration at this center. Results of DFT calculations support the SN2 mechanism and demonstrate
已经开发出一种通用的方法,可通过类似S N 2的反应,将叠氮离子与各种供体-受体环丙烷开环。这种高度区域选择性和立体选择性的过程是通过亲核攻击环丙烷的更取代的C2原子进行的,该中心的构型完全反转。DFT计算结果支持S N2机理,证明环丙烷的相对实验反应性与计算出的能垒之间具有良好的定性相关性。该反应为多种多官能叠氮化物提供了一种简单的方法,产率高达91%。这些叠氮化物具有很高的合成效用,并参与了面向多样性的合成,这是通过已开发的将其转变为五元,六元和七元N杂环以及复杂的环状化合物的多径策略证明的。包括天然产物和药物,如(-)-尼古丁和阿托伐他汀。
Ring-Opening 1,3-Dichlorination of Donor–Acceptor Cyclopropanes by Iodobenzene Dichloride
作者:Lennart K. B. Garve、Philip Barkawitz、Peter G. Jones、Daniel B. Werz
DOI:10.1021/ol5029139
日期:2014.11.7
Donor–acceptor cyclopropanes are reacted with iodobenzenedichloride to afford ring-opened products bearing chlorine atoms in the 1- and 3-positions, adjacent to the donor and acceptor groups. A variety of different donors (e.g., alkyl, aryl, N, and O) and acceptor moieties (e.g., ketones, diesters, and dinitriles) are used.
dioxygenation and diamination of alkenes have been previously developed. In this study, the potential application of hypervalent iodine(III) reagent was successfully extended to the dialkylation and cyclopropa(e)nation of unsaturated alkenes and alkynes. The reactions of alkenes with malononitrile and other active methylene compounds as the carbon nucleophiles give access to multisubstituted cyclopropane
作者:Akira Yoshimura、Steven R. Koski、Brent J. Kastern、Jonathan M. Fuchs、T. Nicholas Jones、Roza Y. Yusubova、Victor N. Nemykin、Viktor V. Zhdankin
DOI:10.1002/chem.201402372
日期:2014.5.12
An efficient, transition metal‐free procedure for the cyclopropanation of alkenes using malononitrile and the LiI‐tBuOCl combination under mild reaction conditions is described. The reaction mechanism most likely involves tBuOI generated in situ from LiI and tBuOCl. The utility of this new methodology has been demonstrated by the synthesis of a potential HIV‐1 RT inhibitor.