2621-78-5Relevant articles and documents
Synthesis of (alkoxycarbonyloxy)methyl, (acyloxy)methyl and (oxodioxolenyl)methyl carbamates as bioreversible prodrug moieties for amines
Li, Zhong,Bitha, Panayota,Lang Jr., Stanley A.,Lin, Yang-I
, p. 2909 - 2912 (1997)
Synthesis of (alkoxycarbonyloxy)methyl carbamates of secondary amines was developed, and it was extended to (acyloxy)methylation of benzylmethylamine and (oxodioxolenyl)methylation of benzylamine, benzylmethylamine, and L-phenylalanine.
Remarkably Efficient Iridium Catalysts for Directed C(sp2)-H and C(sp3)-H Borylation of Diverse Classes of Substrates
Chattopadhyay, Buddhadeb,Hassan, Mirja Md Mahamudul,Hoque, Md Emdadul
supporting information, p. 5022 - 5037 (2021/05/04)
Here we describe the discovery of a new class of C-H borylation catalysts and their use for regioselective C-H borylation of aromatic, heteroaromatic, and aliphatic systems. The new catalysts have Ir-C(thienyl) or Ir-C(furyl) anionic ligands instead of the diamine-type neutral chelating ligands used in the standard C-H borylation conditions. It is reported that the employment of these newly discovered catalysts show excellent reactivity and ortho-selectivity for diverse classes of aromatic substrates with high isolated yields. Moreover, the catalysts proved to be efficient for a wide number of aliphatic substrates for selective C(sp3)-H bond borylations. Heterocyclic molecules are selectively borylated using the inherently elevated reactivity of the C-H bonds. A number of late-stage C-H functionalization have been described using the same catalysts. Furthermore, we show that one of the catalysts could be used even in open air for the C(sp2)-H and C(sp3)-H borylations enabling the method more general. Preliminary mechanistic studies suggest that the active catalytic intermediate is the Ir(bis)boryl complex, and the attached ligand acts as bidentate ligand. Collectively, this study underlines the discovery of new class of C-H borylation catalysts that should find wide application in the context of C-H functionalization chemistry.
Application of Ag/TFPG-DMB COF in carbamates synthesis via CO2 fixation reaction and one-pot reductive N-formylation of nitroarenes under sunlight
Biswas, Surajit,Hazra Chowdhury, Arpita,Hazra Chowdhury, Ipsita,Islam, Sk. Manirul
, (2020/06/25)
We have designed mesoporous AgNPs decorated COF (Ag/TFPG-DMB COF) nanomaterial which has been formed by an easy ex-situ synthetic method. The synthesized material is characterized by FTIR, PXRD, UV–vis, N2 adsorption–desorption studies, TEM, FESEM and XPS. The material showed the generation of identical mesopore at 3.9 nm. It is observed that the material can perform as both thermally and photochemically active catalyst for carbamate synthesis and one-pot reduction and N-formylation of nitroarenes respectively. The catalytic activity of the Ag/ TFPG-DMB COF nanomaterial is checked for green synthesis of carbamates from different amines and alcohols under 1 atmospheric pressure of CO2 with excellent yield (upto 95 %) as well as with high TOF value (182 h?1) and high selectivity. Additionally, the Ag/ TFPG-DMB COF nanomaterial is also applied as a potentially active photocatalyst for one-pot nitroarene reduction along with N-formylation reaction under sunlight irradiation in green reaction conditions with exceptionally high yield of formylated products upto 99 % as well as with high TOF value (762 h ?1). The catalyst efficiently reduced and formylated para-nitrophenol, a potential water pollutant, which elaborates its scope as an efficient catalyst for water purification also. The catalyst recyclability is also checked for five reaction cycles for both the reactions and the Ag/TFPG-DMB COF material showed outstanding recycling ability without any noticeable leaching of active metal or catalyst degradation.
Evaluation of ethyl: N -(2-phenethyl) carbamate analogues as biofilm inhibitors of methicillin resistant Staphylococcus aureus
Stephens, Matthew D.,Yodsanit, Nisakorn,Melander, Christian
, p. 6853 - 6856 (2016/07/21)
A small molecule library consisting of 45 compounds was synthesized based on the bacterial metabolite ethyl N-(2-phenethyl) carbamate. Screening of the compounds revealed a potent analogue capabale of inhibiting several strains of Methicillin Resistant S. aureus biofilms with low to moderate micromolar IC50 values.
BMIm HCO3: an ionic liquid with carboxylating properties. Synthesis of carbamate esters from amines
Di Nicola,Arcadi,Rossi
supporting information, p. 9895 - 9898 (2016/12/07)
1-Butyl-3-methylimidazolium hydrogen carbonate (BMIm HCO3) was used as an ionic liquid with carboxylating properties able to convert, in the presence of an alkyl halide, amines into the corresponding carbamate esters. Moderate to good yields of
An efficient one-pot synthesis of: N, N ′-disubstituted ureas and carbamates from N -acylbenzotriazoles
Singh, Anoop S.,Kumar, Dhananjay,Mishra, Nidhi,Tiwari, Vinod K.
, p. 84512 - 84522 (2016/10/12)
A facile and high-yielding one-pot synthesis of carbamates and N,N′-disubstituted symmetrical ureas from N-acylbenzotriazoles has been devised. It is believed that, the intermediate acyl-azide undergo Curtius rearrangement and in different solvents gives different products i.e. carbamates in alcohols and N,N′-disubstituted symmetrical urea in THF.
Heterobimetallic dinuclear lanthanide alkoxide complexes as acid-base bifunctional catalysts for synthesis of carbamates under solvent-free conditions
Zeng, Ruijie,Bao, Linquan,Sheng, Hongting,Sun, Lili,Chen, Man,Feng, Yan,Zhu, Manzhou
, p. 78576 - 78584 (2016/09/09)
Heterobimetallic dinuclear lanthanide alkoxide complexes Ln2Na8(OCH2CH2NMe2)12(OH)2 [Ln: I (Nd), II (Sm), III (Yb) and IV (Y)] were used as efficient acid-base bifunctional catalysts for the synthesis of carbamates from dialkyl carbonates and amines as well as the N-Boc protection of amines. The cooperative catalysts showed high catalytic activity and a wide scope of substrates with good to excellent yields under solvent-free conditions. The systems have shown higher catalytic activities due to the noteworthy synergistic interactions of Lewis acid center-Br?nsted basic center. The comparison of catalytic efficiency between mono- and dinuclear heterobimetallic lanthanide alkoxide analogues was also investigated.
N-Substituted carbamate synthesis using urea as carbonyl source over TiO2-Cr2O3/SiO2 catalyst
Wang, Peixue,Ma, Yubo,Liu, Shimin,Zhou, Feng,Yang, Benqun,Deng, Youquan
, p. 3964 - 3971 (2015/07/15)
The use of urea as an active form of carbon dioxide is a feasible way to substitute phosgene in the chemical industry. This paper reports an effective route for the synthesis of N-substituted carbamates from amines, urea and alcohols. Under the optimized reaction conditions, several important N-substituted carbamates were successfully synthesized in 95-98% yields over a TiO2-Cr2O3/SiO2 catalyst. The catalyst could be reused for several runs without deactivation. The catalysts were characterized by BET, XPS, XRD, and TPD, which suggested that the strength and amount of the acidic and basic sites might be the major reason for the high catalytic activity of TiO2-Cr2O3/SiO2.
Amide synthesis from alcohols and amines catalyzed by a RuII-N-heterocyclic carbene (NHC)-carbonyl complex
Saha, Biswajit,Sengupta, Gargi,Sarbajna, Abir,Dutta, Indranil,Bera, Jitendra K.
, p. 124 - 130 (2014/12/11)
Treatment of [Ru2(CO)4(CH3CN)6](BF4)2 with 3-methyl-1-(pyridin-2-yl)-imidazolium bromide in the presence of tetrabutylammonium bromide at room temperature in dichloromethane affords a RuII-N-heterocyclic carbene-carbonyl complex [Ru(py-NHC)(CO)2Br2] (1). Catalyst 1 displays diverse substrate scope for phosphine-free acceptorless coupling between alcohols and amines to amides at low catalyst loading. A RuII-dihydride/Ru0 sequence is proposed in the catalytic cycle.
Direct reductive amination using triethylsilane and catalytic bismuth(III) chloride
Matsumura, Takehiko,Nakada, Masahisa
, p. 1829 - 1834 (2014/03/21)
Direct reductive amination (DRA) using triethylsilane (TESH) and catalytic bismuth(III) chloride (BiCl3) is described for the first time. The use of TESH and BiCl3 provides easy handling, low cost, non-toxicity, and a mild Lewis acid activity, thereby meeting the demand for green and sustainable chemistry. The developed DRA is highly chemoselective and applicable to less-basic amines. The experimental results of this study revealed that the developed DRA could be catalyzed by BiCl3, which was gradually reduced to Bi(0) or bismuth with a low valency by TESH, but TESCl, Bi(0), and Bi(0) with TESCl catalyzed the DRA to some extent.
