The alkylation of aromatic compounds with aldehydes and ketones in
the presence of a variety of metal cation-exchanged montmorillonites
(Mn+-mont;
Mn+ = Zr4+,
Al3+, Fe3+, Zn2+, H+,
Na+) has been investigated. Al3+- and
Zr4+-Monts are revealed to be effective as catalysts, while
no reaction takes place with Na+-mont.
Al3+-Mont-catalysed alkylation of phenol with several
aldehydes produces mainly or almost solely the corresponding
gem-bis(hydroxyphenyl)alkanes (bisphenols) in good yields, while that
with several ketones affords selectively the corresponding alkylphenols
in moderate to good yields. The alkylation always occurs at the carbonyl
carbon without any skeletal rearrangement and the kind of products
depends much on the steric hindrance of an electrophilic intermediary
carbocation. The alkylation of anisole, veratrole and p-cresol
proceeds well, while that of toluene, benzene, chlorobenzene and
nitrobenzene scarcely occurs.
Synthesis of the 9-mesityl-10-phenyl-9-boraanthracene anion
作者:R. van Veen、F. Bickelhaupt
DOI:10.1016/s0022-328x(00)81597-1
日期:1972.10
Derivatives of 10-phenyl-9,10-dihydro-9-boraanthracene were synthesized from tris(2-benzhydrylphenyl)boroxin by pyrolysis with lithiumaluminumhydride and tributyl borate. 10-Phenyl-9-boraanthracene could not be obtained from a chemical reaction or on electron impact. The isolation of lithium 9-mesityl-10-phenyl-9-boraanthracene as a crystalline non-solvated salt is described.
Additive for heat-sensitive recording material, the recording material, and method for production of the recording material
申请人:SHOWA DENKO KABUSHIKI KAISHA
公开号:EP0373251A1
公开(公告)日:1990-06-20
A hydantoin compound of the formula:
(wherein R stands for an alkyl group of 8 to 20 carbon atoms) increases the sensitivity of a color developing reaction of a heat-sensitive recording material and enhances the high-speed recording property of the recording material without sacrifice of the whiteness thereof. The heat-sensitive recording material containing the hydantoin compound is novel to the art.
式中的一种海因化合物:
(其中 R 代表 8 至 20 个碳原子的烷基)可提高热敏记录材料显色反应的灵敏度,并增强记录材料的高速记录性能,同时不影响其白度。含有海因化合物的热敏记录材料是本领域的新技术。
Polyimides, process for producting the same and photosensitive composition containing the same
申请人:Nippon Mektron, Limited
公开号:EP0953590A1
公开(公告)日:1999-11-03
Polyimide is produced by reacting two kinds of diamine compounds consisting of diaminopolysiloxane and a hydroxyl group-containing diamine or three kinds of diamine compounds consisting of diaminopolysiloxane, a hydroxyl group-containing diamine and an aromatic or alicyclic diamine with a dicarboxylic acid anhydride having a 2,5-dioxotetrahydrofuryl group as one acid anhydride group, thereby once forming a polyamic acid, and subjecting the polyamic acid to polyimidization reaction. The resulting polyimide itself is soluble in low boiling organic solvents for general purpose use, typically methyl ethyl ketone. A photosensitive composition comprising the polyimide, a photo crosslinking agent and a photo acid-generating agent forms a negative type polyimide pattern upon development with an aqueous alkali solution.
A novel copolymer, graft copolymer, copolymer particles, flame retardant, and resin composition are provided. A copolymer including a polymer (A) segment having a glass transition temperature not more than -10°C, and a polymer (C) segment having at least a unit derived from a monomer (B) which has two or more of aromatic rings and one or more radical reactive groups in one molecule; a graft copolymer having the component (B) grafted onto the component (A); and copolymer particles thereof are obtained. A flame retardant resin composition is obtained by using the copolymer as a flame retardant and blending the flame retardant with the resin.