Synthesis of medium-sized lactones by the copper(I)chloride/2,2′-bipyridine-catalyzed cyclization of di- and trichloroacetates
作者:Frank O.H. Pirrung、Henk Hiemstra、W. Nico Speckamp、Bernard Kaptein、Hans E. Schoemaker
DOI:10.1016/s0040-4020(01)89549-1
日期:1994.1
Medium-sized lactones (eight- to eleven-membered rings) are efficiently formed by Cu(bpy)Cl catalyzed cyclization of various alkenyl di- and trichloroacetates at temperatures between 80 and 190°C in 1,2-dichloroethane or benzene as solvents. The mechanism of the alkene addition reaction is best understood as a chlorine atom transfer process through radical type intermediates. Exclusive endo-cyclization
New and improved catalysts for transition metal catalysed radical reactions
作者:Floryan de Campo、Dominique Lastécouères、Jean-Baptiste Verlhac
DOI:10.1039/a804915g
日期:——
New CuI and FeII complexes displayed considerable improvements in atom transfer radical addition reactions.
新的 CuI 和 FeII 复合物在原子转移自由基加成反应中表现出相当大的改进。
GAS-BARRIER RESIN COMPOSITION AND USE THEREOF
申请人:Showa Denko K.K.
公开号:EP3660105A1
公开(公告)日:2020-06-03
The present invention relates to a gas-barrier resin composition, including: a gas-barrier resin (A) having an oxygen permeability coefficient of 1.0×10-14 (cm3·cm/cm2·s·Pa) or less; and a copolymer (B) containing monomer structural units represented by the formula (1), the formula (2), and the formula (3):
where: R1 represents a hydrogen atom or a methyl group; R2 represents a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with a halogen atom, a hydroxy group, an alkoxy group, or an amino group; l, m, and n represent numerical values representing molar proportions of the respective monomer structural units, and n may represent 0; and p represents an integer of from 1 to 4, wherein a ratio of a mass of the copolymer (B) to a total mass of the gas-barrier resin (A) and the copolymer (B) is from 1 mass% to 40 mass%. Preferred as the gas-barrier resin (A) are a vinyl alcohol-based resin (A1), a polyamide-based resin (A2), and a polyester-based resin (A3). The present invention can provide a resin composition ameliorated in low flexibility and low impact resistance, which are drawbacks of a gas-barrier resin, without impairing excellent gas barrier properties of the gas-barrier resin.
New copper(I) and iron(II) complexes for atom transfer radical macrocyclisation reactions
作者:Floryan De Campo、Dominique Lastécouères、Jean-Baptiste Verlhac
DOI:10.1039/a908245j
日期:——
New Cu(I) and Fe(II) complexes have been synthesized and proved to be efficient catalysts for atom transfer radical addition (ATRA) reactions. The catalytic activity was found to be greater than existing atom transfer systems based upon CuCl(bipyridine) or RuCl2(PPh3)3, for example. The addition of a reducing agent considerably improved the efficiency of the usual procedures.