A series of 3-(alkoxycarbonyloxy)-2-methylenealkanoate (1), a sulfonate (5), and an N,N-dimethylamide (6) were carbonylated using Pd(0) complexes as catalyst to give alkylidenesuccinate (2), and analogues in moderate to good yields. The stereoselectivity for E and Z isomers of carbonylation products was found to differ remarkably, depending on the three types of substrates which always include an electron-withdrawing group. The results are explained in terms of the plausible MM2 simulation through the model compounds.
Development of n-Type Semiconductor Based on Cyclopentene- or Cyclohexene-Fused [C<sub>60</sub>]-Fullerene Derivatives
Properties of cydopentene- or cyclohexene-fused [C-60]-fullerene derivatives as the acceptor in photovoltaic cells have been investigated by use of poly(3-hexylthiophene) (P3HT) as the model donor polymer. Several cyclopentene- or cyclohexene-fused [C-60]-fullerene derivatives show high power conversion efficiency (PCB). The highest PCE was obtained for 3',6'-dihydro-4'-phenoxycarbonyl-6'-methylbenzo[1,9][5,6] (C-60-I-h)fullerene (3.2%); this is superior to that of [C-60]-PCBM with the P3HT polymer under the same experimental conditions. PCE of the OPV devices with alkyl-substituted cydohexene-fused [C-60],fullerenes depended on the alkyl substituent on the cyclohexene ring; compounds with substituents of odd-number alkyl groups showed better PCE than those compounds possessing even-number alkyl groups.
Lewis Acid-Enhanced Reactivity of .alpha.,.beta.-Unsaturated Esters and Amides toward Radical Addition
作者:Hirokazu Urabe、Koki Yamashita、Ken Suzuki、Katsushige Kobayashi、Fumie Sato
DOI:10.1021/jo00117a003
日期:1995.6
Unprecedented <i>E</i>-stereoselectivity on the sigmatropic Hurd–Claisen rearrangement of Morita–Baylis–Hillman adducts: a joint experimental–theoretical study
作者:Vinicius Sobral Silva、Terezinha Alves Tolentino、Tiago Costa Alves Fontoura Rodrigues、Fernanda Ferrari Martins Santos、Daniel Francisco Scalabrini Machado、Wender Alves Silva、Heibbe Cristhian Benedito de Oliveira、Angelo Henrique Lira Machado
DOI:10.1039/c9ob00533a
日期:——
first systematic investigation of the tandem mercury(II) catalysed transvinylation/Hurd–Claisen rearrangement of MBH adducts derived from alkyl acrylates. This is the first report of E-selectivity for MBH adducts with alkyl side chains and is complementary to the previously reported Johnson–Claisen and Eschenmoser–Claisen rearrangements. The rearrangement products were obtained in good yields and could