(Tosylimino)phenyl-λ<sup>3</sup>-iodane as a Reagent for the Synthesis of Methyl Carbamates via Hofmann Rearrangement of Aromatic and Aliphatic Carboxamides
作者:Akira Yoshimura、Matthew W. Luedtke、Viktor V. Zhdankin
DOI:10.1021/jo300007c
日期:2012.2.17
A new, mild procedure for the Hofmann rearrangement of aromatic and aliphatic carboxamides using (tosylimino)phenyl-λ3-iodane, PhINTs, as a reagent is reported. Because of the mild reaction conditions, this method is particularly useful for the Hofmann rearrangement of substituted benzamides, which usually afford complex reaction mixtures with other hypervalent iodine oxidants. The mild reaction conditions
Hofmann Rearrangement of Carboxamides Mediated by Hypervalent Iodine Species Generated in Situ from Iodobenzene and Oxone: Reaction Scope and Limitations
作者:Aleksandra A. Zagulyaeva、Christopher T. Banek、Mekhman S. Yusubov、Viktor V. Zhdankin
DOI:10.1021/ol101993q
日期:2010.10.15
Alkylcarboxamides can be converted to the respective amines by Hofmann rearrangement using hypervalent iodine species generated in situ from PhI and Oxone in aqueous acetonitrile. On the basis of this reaction, a convenient experimental procedure for the preparation of alkylcarbamates using Oxone as the oxidant in the presence of iodobenzene in methanol has been developed. An efficient method for direct
The synthesis of alkyl carbamates from primary aliphatic amines and dialkyl carbonates in supercritical carbon dioxide
作者:Maurizio Selva、Pietro Tundo、Alvise Perosa
DOI:10.1016/s0040-4039(01)02390-5
日期:2002.2
130°C and in the presence of compressed CO2, primary aliphatic amines [RNH2, R=C10H21, C8H17, cHex, 1-(C10H7)CH2] react with organic carbonates (R′OCO2R; R′=Me, Et) to give alkyl carbamates (RNHCO2R′, 1). Although CO2 promotes the reaction also at a low pressure, good yields (∼80%) of 1 are achievable only with supercritical carbondioxide (scCO2) at 90 bar, which inhibits the formation of N-methylated
在130°C且存在压缩CO 2的情况下,伯脂肪族胺[RNH 2,R = C 10 H 21,C 8 H 17,cHex,1-(C 10 H 7)CH 2 ]与有机碳酸酯( R′OCO 2 R; R′= Me,Et)得到氨基甲酸烷基酯(RNHCO 2 R′,1)。尽管CO 2在低压下也能促进反应,但仅在90 bar的超临界二氧化碳(scCO 2)的情况下,才能达到1的良好收率(〜80%),这会抑制N-甲基化副产物的形成。
Process for producing isocyanates
申请人:MITSUBISHI GAS CHEMICAL COMPANY, INC.
公开号:EP0672653A1
公开(公告)日:1995-09-20
Provided is a process for producing isocyanates from carbamic acid esters which comprises thermally decomposing carbamic acid esters in the presence of a catalyst containing at least one compound selected from the group consisting of organic sulfonic acids and alkaline metal salts of organic sulfonic acids. Thereby, a high thermal decomposition rate can be provided and isocyanate can be obtained in a high yield.
Disclosed is a flame retarding resin composition comprising (A) one or more epoxy resins; (B) a hardener; and (C) a hardening accelerator, wherein the hardener of the component B is a phosphorus-containing compound represented by the following formula (I):
1
wherein each symbol is as defined below. The flame retarding resin composition of the present invention without adding halogen or other flame retardants has high flame retardancy and excellent heat resistance. The flame retarding resin composition of the present invention is suitably useful in the application of thermosetting resins, thermoplastic resins, bonding sheets, composite materials, laminated plates, printed circuit boards, copper foil adhesives, inks used for build-up process, semiconductor molding materials and the like.
本发明公开了一种阻燃树脂组合物,该组合物包含(A)一种或多种环氧树脂;(B)一种固化剂;以及(C)一种硬化促进剂,其中成分 B 的固化剂是由下式(I)表示的含磷化合物:
1
其中各符号定义如下。本发明的阻燃树脂组合物不添加卤素或其他阻燃剂,具有高阻燃性和优异的耐热性。本发明的阻燃树脂组合物适用于热固性树脂、热塑性树脂、粘合片、复合材料、层压板、印刷电路板、铜箔粘合剂、用于堆积工艺的油墨、半导体成型材料等。