Dehydrogenative Synthesis of Carbamates from Formamides and Alcohols Using a Pincer-Supported Iron Catalyst
作者:Tanya M. Townsend、Wesley H. Bernskoetter、Nilay Hazari、Brandon Q. Mercado
DOI:10.1021/acscatal.1c02718
日期:2021.8.20
already been demonstrated that the transient isocyanate generated from dehydrogenation of the formamide can be trapped with amines to form ureas and, in principle, the isocyanate could also be trapped with thiols to form thiocarbamates. Competition experiments indicate that trapping of the transient isocyanate with amines to produce ureas is faster than trapping with an alcohol to produce carbamates
Cyclic tetramers of a five-membered palladacycle based on a head-to-tail-linked isocyanate dimer and their reactivity in cyclotrimerization of isocyanates
作者:Seon Gye Lee、Keun-Young Choi、Yong-Joo Kim、SuJin Park、Soon W. Lee
DOI:10.1039/c5dt00534e
日期:——
Reactions of [Pd(styrene)(PR3)2], generated from trans-[PdEt2(PR3)2] and styrene, with 2 equiv. of benzyl isocyanate in THF at room-temperature afforded unusual cyclic Pd-tetramers of five-membered rings consisting of organic isocyanatedimers and palladium, [Pd(PR3)–C(O)N(R)C(O)N(R)–}]4 (PR3 = PMe3, 1; PR3 = PMe2Ph, 2). Additionally, a cyclic trimer, (RNCO)3, 3 (R = benzyl) was produced as a catalytic
Reactivities of zero-valent group 10 complexes toward organic isocyanates: synthesis of metallacycles containing dimeric isocyanate units, isocyanate cyclotrimerization, and computational chemistry
作者:Young-Sung Han、Kang-Yeoun Jung、Yong-Joo Kim、Kyoung Koo Baeck、Gang Min Lee、Soon W. Lee
DOI:10.1039/c9nj03332g
日期:——
4-methoxybenzyl), depending on the alkyl substituent on R-NCO. Interestingly, these reactions afford cyclic trimers as catalytic products when two equivalents or excess amounts of benzyl isocyanate are used. In contrast, reactions of [Pt(olefin)(PR3)2] with two equivalents of an alkyl or aryl isocyanate afford only the five-membered platinacycle, namely cis-[Pt–N(R)C(O)N(R)C(O)–}(PMe3)2] (R = 3-methylbenzyl
Macrocyclic complexes containing a platinacycle or palladacycle composed of an isocyanate dimer unit: Reactivity towards isocyanides and cyclotrimerization of isocyanates
作者:Jun-Hwan Choi、Kang-Yeoun Jung、Yong-Joo Kim、Hye Jin Im、Soon W. Lee
DOI:10.1016/j.poly.2016.05.061
日期:2016.10
cyclic products as an assembly of four platinacycles or palladacycles, [M(PR3)–N(R)C(O)N(R)C(O)–}]4, were readily obtained. These cyclic tetramers were cleaved using tert-butyl isocyanide (CN–tbutyl, 4 equiv.), affording the corresponding monomeric complexes, [M(PR3)(CN–tbutyl)–N(R)C(O)N(R)C(O)–}] (M = Pt, Pd). An unusual cyclotrimerization of organic isocyanates catalyzed by zerovalent Pt complexes
Process for the preparation of organic isocyanate compounds
申请人:Kao Soap Co., Ltd.
公开号:US04056547A1
公开(公告)日:1977-11-01
A process for preparing organic isocyanate compounds characterized by reacting a chloromethyl group-containing compound having the formula: (X).sub.n RCH.sub.2 Cl wherein X, which can be the same or different, is chlorine, alkyl, cycloalkyl, alkenyl, phenyl, chloromethylphenyl or chloromethyl, n is 0 or an integer of 1 to 3, and R is an aromatic hydrocarbon radical or an olefin radical, With an alkali cyanate, in the presence of a catalyst composition comprising (a) a cuprous salt in an amount of 0.1 to 20% by weight, based on said chloromethyl group-containing compound, and (b) a tertiary amine compound or quaternary ammonium compound in an amount equivalent to 0.05 to 1.25 gram atoms of nitrogen per gram mole of said cuprous salt, in a high-boiling-point solvent having a dieelectric constant (.epsilon.) not higher than 20, at a reaction temperature of 150.degree. to 250.degree. C, for 0.1 to 10 hours.