](/Databaselist/images/loading.webp)
1609-86-5Relevant academic research and scientific papers
Isocyanates from Alkyl and Aralkyl Halides
Boyer, Joseph H.,Manimaran, Thanikavelu
, p. 907 (1987)
Alkyl and aralkyl halides were converted to isocyanates (63percent-89percent) by treatment with the silver salt of nitrocyanamide.This new reaction offers the first direct conversion of an organic halide to an isocyanate that is general, efficient, and facile.
Mechanistic Basis for Efficient, Site-Selective, Aerobic Catalytic Turnover in Pd-Catalyzed C-H Imidoylation of Heterocycle-Containing Molecules
Tereniak, Stephen J.,Stahl, Shannon S.
, p. 14533 - 14541 (2017)
A recently reported Pd-catalyzed method for oxidative imidoylation of C-H bonds exhibits unique features that have important implications for Pd-catalyzed aerobic oxidation catalysis: (1) The reaction tolerates heterocycles that commonly poison Pd catalysts. (2) The site selectivity of C-H activation is controlled by an N-methoxyamide group rather than a suitably positioned heterocycle. (3) A Pd0 source, Pd2(dba)3 (dba = dibenzylideneacetone), is superior to Pd(OAc)2 as a precatalyst, and other PdII sources are ineffective. (4) The reaction performs better with air, rather than pure O2. The present study elucidates the origin of these features. Kinetic, mechanistic, and in situ spectroscopic studies establish that PdII-mediated C-H activation is the turnover-limiting step. The tBuNC substrate is shown to coordinate more strongly to PdII than pyridine, thereby contributing to the lack of heterocycle catalyst poisoning. A well-defined PdII-peroxo complex is a competent intermediate that promotes substrate coordination via proton-coupled ligand exchange. The effectiveness of this substrate coordination step correlates with the basicity of the anionic ligands coordinated to PdII, and Pd0 catalyst precursors are most effective because they selectively afford the PdII-peroxo in situ. Finally, elevated O2 pressures are shown to contribute to background oxidation of the isonitrile, thereby explaining the improved performance of reactions conducted with air rather than 1 atm O2. These collective results explain the unique features of the aerobic C-H imidoylation of N-methoxybenzamides and have important implications for other Pd-catalyzed aerobic C-H oxidation reactions.
N-DIFLUORPHOSPHORYL-N',N''-BIS(T-BUTYL)-SCWEFELTRIIMID
Tesky, F. M.,Mews, R.
, p. 399 - 404 (1988)
(t-BuN=)2S=NPOF2 (5) is prepared in 55 percent yield from (t-BuNH=)3S and OPF2NCO.In moist ether water is added to 5 forming (t-Bu-N-)2S(O)NPOF2 (6) almost quantitatively.
Monomeric (Pentamethylcyclopentadienyl)iridium Imido Compounds: Synthesis, Structure, and Reactivity
Glueck, David S.,Wu, Jianxin,Hollander, Frederick J.,Bergman, Robert G.
, p. 2041 - 2054 (1991)
The monomeric terminal imido complexes Cp*IrNR (Cp* = η5-C5Me5; 1a, R = t-Bu; 1b, R = SiMe2t-Bu; 1c, R = 2,6-Me2C6H3; 1d, R = 2,6-i-Pr2C6H3) were prepared from [Cp*IrCl2]2 (2) and 4 equiv of the corresponding lithium amide LiNHR in THF. In addition, the complexes Cp*Ir(RNH2)Cl2 (3a, R = t-Bu; 3d, R = 2,6-i-Pr2C6H3) were made from an amine and [Cp*IrCl2]2 (2) and dehydrochlorinated with KN(SiMe3)2 to provide an alternate route to 1a,d. Efficient exchange occurred between 1a and arylamines, leading to 1c,d and tert-butylamine. tert-Butylimido complex 1a, a weak nucleophile, reacted with MeI to form [Cp*IrI2]2 and Me3Nt-Bu+I-. Coupling of the imido ligand in 1a with CNt-Bu and CO gave Cp*Ir(t-BuNCNt-Bu)(CNt-Bu) (4) and Cp*Ir(t-BuNCO)(CO) (5a), respectively. Cp*IrPPh3(t-BuNCO) (5b) was formed from 1a, PPh3, and CO. The bridging imido complex Cp*IrNt-Bu(dppePt) (6, dppe = 1,2-bis(diphenylphosphino)ethane) was prepared from 1a and dppePt(C2H4). Complex 1a and CO2 gave the cycloadduct Cp*Ir(Nt-BuOCO) (7a), which added PPh3 to form Cp*IrPPh3(Nt-BuOCO) (7b). Two equivalents of dimethylacetylenedicarboxylate reacted with 1a to yield the pyrrole complex Cp(Ir(η4-RCCRNt-BuRCCR) (8, R = CO2Me). Maleic anhydride was added to 1a to give Cp*Ir[Nt-BuC(O)CH=CHCO2] (9a), which reacted with CO to yield Cp*Ir(CO)[Nt-BuC(O)CH=CHCO2] (9b). Compounds 1a-d, 7a, and 8 were structurally characterized by X-ray diffraction; imido complexes 1a-d have short Ir-N distances and nearly linear Ir-N-C(Si) angles, consistent with the presence of a metal-nitrogen triple bond.
Phosphazenes: Efficient organocatalysts for the catalytic hydrosilylation of carbon dioxide
Courtemanche, Marc-André,Légaré, Marc-André,Rochette, étienne,Fontaine, Frédéric-Georges
, p. 6858 - 6861 (2015)
Phosphazene superbases are efficient organocatalysts for the metal-free catalytic hydrosilylation of carbon dioxide. They react with CO2 to form the respective phosphine oxides, but in the presence of hydrosilanes, CO2 can be selectively reduced to silyl formates, which can in turn be reduced to methoxysilanes by addition of an extra loading of silanes. Activities reach a TOF of 32 h-1 with a TON of 759. It is also shown that unexpectedly, N,N-dimethylformamide can reduce CO2 to a mixture of silyl formates, acetals and methoxides in the absence of any catalyst.
2-(aryl (azacycloalkane-1-yl) methyl) phenol derivatives and uses thereof
-
Paragraph 0293-0295, (2021/07/24)
The invention discloses 2-(aryl (azacycloalkane-1-yl) methyl) phenol derivatives and application thereof, and belongs to the technical field of medicines. The invention provides a compound shown in a formula I or pharmaceutically acceptable salt thereof. The series of compounds have good inhibitory activity on the histone demethylase KDM4 family in vitro, the median inhibitory concentration (IC50) of most molecules on KDM4D is less than 500 nM, and the compounds have good inhibitory effect on proliferation of various human tumor cell strains in vitro, so that the series of compounds provide a new effective choice for developing targeted histone demethylase KDM4D drugs and preparing drugs for treating and/or preventing cancers and reproductive system diseases, and have good application prospects.
Reversible CO2 fixation by N-heterocyclic imines forming water-stable zwitterionic nitrogen-base-CO2 adducts
Wilm, Lukas F. B.,Eder, Tobias,Mück-Lichtenfeld, Christian,Mehlmann, Paul,Wünsche, Marius,Bu?, Florenz,Dielmann, Fabian
supporting information, p. 640 - 648 (2019/02/14)
Zwitterionic Lewis base adducts between nitrogen bases and CO2 play a pivotal role as transient intermediates in many projects aiming at CO2 capture, storage and utilization. Yet, fundamental questions about the required parameters for the formation of isolable adducts remain and only a single adduct (TBD-CO2) has been characterized unequivocally. Using a combination of NMR spectroscopy, single-crystal X-ray diffraction, IR spectroscopy and quantum chemistry, we systematically explore the formation and properties of the CO2 adducts with amidines (DBN), guanidines (MTBD) and N-heterocyclic imines. Spectroscopic and theoretical results show that the stability of the NHI-CO2 adducts is largely governed by the nature of the N-heterocycle and the substituent at the exocyclic nitrogen atom. The surprising stability of some NHI-CO2 adducts towards hydrolysis can be ascribed to the hydrophobic CO2 binding site of the nitrogen bases and offers new opportunities in the field of CO2 capture and utilization.
Synthesis method of tert-butyl isocyanate
-
Paragraph 0008; 0023-0028, (2018/11/04)
The invention relates to a synthesis method of tert-butyl isocyanate. The synthesis method comprises following steps: (1) evenly mixing a proper amount of catalyst and a solvent (90% of the theoretical amount) at a temperature of 90-180 DEG C to obtain a premixed solution, gradually dropwise adding a fed-batch solution into the premixed solution, after addition, maintaining the temperature of reaction solution in a range of 90-180 DEG C, keeping a reflux state, and carrying out reactions for 15 to 25 hours under stirring; and (2) after the reactions (1), delivering the mixed solution to a rotary evaporator, carrying out rotary evaporation, washing, and drying to obtain a tert-butyl isocyanate product. According to the synthesis method, tert-butyl amino formyl chloride directly carries outreactions in an inert solvent to prepare tert-butyl isocyanate; the safety hazard is radically inhibited from the source of the technology, and the preparation method has the advantages of reasonabletechnology, safety, high yield, and low production cost, and does not generate any wastewater, waste gas, or waste solid.
Synthesis method of tertiary butyl isocyanate
-
Paragraph 0053-0088, (2018/09/08)
The invention relates to a synthesis method of tertiary butyl isocyanate. The method comprises the following steps of mixing an inert solvent and para toluene sulfonamide, introducing phosgene at 100DEG C to 120 DEG C, feeding an inert gas for driving gas after reaction, and thus obtaining a first reaction solution; at 0 DEG C to 20 DEG C, dropwise adding tert-butylamine into the first reaction solution, heating and refluxing for 4h or more, and thus obtaining a second reaction solution; separating and purifying the second reaction solution to obtain tertiary butyl isocyanate. According to the synthesis method of tertiary butyl isocyanate, the stability and the yield of the process can be improved, and the purity of the obtained tertiary butyl isocyanate product is higher.
Reaction of N-alkyl-N′-(trimethylsilyl)carbodiimides with nitrating agents. The synthesis of N-(tert-butyl)-N′-nitrocarbodiimide
Churakov,Ioffe,Voronin,Tartakovsky
, p. 56 - 60 (2018/04/27)
Reaction of N-Alk-N′-(trimethylsilyl)carbodiimides (Alk = Me, But) with nitrating agents (N2O5, (NO2)2SiF6) affords alkyl(nitro)cyanamides and N-alkyl-N′-nitrocarbodiimides. The product ratio depends on the reaction conditions. N-(tert-butyl)-N′-nitrocarbodiimide can be obtained in almost pure form. This compound is stable at temperatures below 10 °C. Its structure was confirmed by 1Н, 13C, and 14N NMR. The reaction of N-(tert-butyl)-N′-nitrocarbodiimide with amines provides a new route to N-alkyl(aryl)-substituted N′-(tert-butyl)-N″-nitroguanidines.
