Reductive coupling reaction of aldehydes using indium(III) triflate as the catalyst
摘要:
A reductive coupling reaction was effectively developed to convert an aldehyde to its symmetrical ether. The successful reactions required Et3SiH and CH2Cl2 as the suitable solvent in the presence of a catalytic amount of In(OTf)(3). Various aldehydes were subjected to the method, and each afforded the expected ethers in good to excellent yields. (C) 2014 Elsevier Ltd. All rights reserved.
Salicylic acid copolymers and their metal salts, production process thereof, color-developing agents comprising metal salts of the copolymers and color-developing sheets employing the agents
申请人:MITSUI TOATSU CHEMICALS, Inc.
公开号:EP0268878A2
公开(公告)日:1988-06-01
Disclosed herein are salicylic acid copolymers having a weight average molecular weight of 500 10,000 and obtained (a) by condensing salicylic acid (i) with a benzyl alcohol (ii) and/or benzyl ether (iii) or a benzyl halide (iv) in the presence of an acid catalyst or (b) by reacting a co-condensation resin of (i) and (ii) and/or (iii) with (iv) or (c) by reacting a co-condensation resin of (i) and (ii) and/or (iii) or (iv) with a styrene derivative in the presence of an acid catalyst; multivalent metal salts of the salicylic acid copolymers; color-developing agents comprising the multivalent metal salts; and color-developing sheets suited for pressure-sensitive copying paper and comprising the color-developing agents. Their production processes are also disclosed.
A color-developing composition comprises a multivalent-metal-modified salicylic acid resin (Resin A) and a polycondensation resin (resin B) at a weight ratio of 90-30 to 10-70. Resin A is composed of 5-35 mole% of a structural unit (I) and 65-95 mole% of at least one structural unit (II) or 65-95 mole% of a coupled structural unit of at least one unit (II) and at least one unit (III) and has a weight-average molecular weight of 350-5,000. Resin B is composed of the unit (II) and/or the unit (III) and has a weight-average molecular weight of 350-5,000.
wherein Z represents M/m, M being a metal ion of m valence and m being an integer; R₁ and R₂ represent H or a C₁₋₁₂ alkyl, aralkyl, aryl or cycloalkyl group; R₃ and R₆ represent H or a C₁₋₄ alkyl group; and R₄ and R₅ represent H or CH₃.
一种显色组合物包括一种多价金属改性水杨酸树脂(树脂 A)和一种缩聚树脂(树脂 B),两者的重量比为 90-30 比 10-70。树脂 A 由 5-35 摩尔%的结构单元(I)和 65-95 摩尔%的至少一个结构单元(II)或 65-95 摩尔%的至少一个单元(II)和至少一个单元(III)的耦合结构单元组成,其重量平均分子量为 350-5000。树脂 B 由单元(II)和/或单元(III)组成,重量平均分子量为 350-5000。
其中 Z 代表 M/m,M 为 m 价金属离子,m 为整数;R₁ 和 R₂ 代表 H 或 C₁₋₁₂ 烷基、芳基、芳烷基或环烷基;R₃ 和 R₆ 代表 H 或 C₁₋₄ 烷基;以及 R₄ 和 R₅ 代表 H 或 CH₃。
10.1021/jacs.4c06090
作者:Choi, Shinyoung、Yoon, Ki-Young、Dong, Guangbin
DOI:10.1021/jacs.4c06090
日期:——
practical applications. Here, we have revisited this long-standing challenge and devised a modular and convergent platform to synthesize multifunctional dendrons with all-carbon backbones up to four generations via an in situ functionalization strategy. Enabled by the palladium/norbornenecooperativecatalysis, different functional groups can be introduced to each generation of dendrons during the dendron