872-50-4Relevant articles and documents
Rapid and Mild Lactamization Using Highly Electrophilic Triphosgene in a Microflow Reactor
Fuse, Shinichiro,Komuro, Keiji,Otake, Yuma,Masui, Hisashi,Nakamura, Hiroyuki
supporting information, p. 7525 - 7532 (2021/03/17)
Lactams are cyclic amides that are indispensable as drugs and as drug candidates. Conventional lactamization includes acid-mediated and coupling-agent-mediated approaches that suffer from narrow substrate scope, much waste, and/or high cost. Inexpensive, less-wasteful approaches mediated by highly electrophilic reagents are attractive, but there is an imminent risk of side reactions. Herein, a methods using highly electrophilic triphosgene in a microflow reactor that accomplishes rapid (0.5–10 s), mild, inexpensive, and less-wasteful lactamization are described. Methods A and B, which use N-methylmorpholine and N-methylimidazole, respectively, were developed. Various lactams and a cyclic peptide containing acid- and/or heat-labile functional groups were synthesized in good to high yields without the need for tedious purification. Undesired reactions were successfully suppressed, and the risk of handling triphosgene was minimized by the use of microflow technology.
Preparation of alkylated compounds using the trialkylphosphate
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Paragraph 0184-0185; 0210, (2021/11/02)
[Problem] trialkylphosphate strong base used reaction agent, a carboxylic acid, a ketone, an aldehyde, amine, amide, thiol, ester or Grignard reagent to a variety of substrates, and/or high efficiency to generate a highly stereoselective alkylation reaction, the alkylated compounds capable of producing new means. [Solution] was used as the alkylating agent in the alkylation of compound trialkylphosphate, strongly basic reaction production use. [Drawing] no
Regio- And Stereoselective (S N2) N -, O -, C - And S -Alkylation Using Trialkyl Phosphates
Banerjee, Amit,Hattori, Tomohiro,Yamamoto, Hisashi
, (2021/06/16)
Bimolecular nucleophilic substitution (S N 2) is one of the most well-known fundamental reactions in organic chemistry to generate new molecules from two molecules. In principle, a nucleophile attacks from the back side of an alkylating agent having a suitable leaving group, most commonly a halide. However, alkyl halides are expensive, very harmful, toxic and not so stable, which makes them problematic for laboratory use. In contrast, trialkyl phosphates are inexpensive, readily accessible and stable at room temperature, under air, and are easy to handle, but rarely used as alkylating agents in organic synthesis. Here, we describe a mild, straightforward and powerful method for nucleophilic alkylation of various N -, O -, C - and S -nucleophiles using readily available trialkyl phosphates. The reaction proceeds smoothly in excellent yield, and quantitative yield in many cases, and covers a wide range of substrates. Further, the rare stereoselective transfer of secondary alkyl groups has been achieved with inversion of configuration of chiral centers (up to 98% ee).
Triazinetriamine-derived porous organic polymer-supported copper nanoparticles (Cu-NPs@TzTa-POP): an efficient catalyst for the synthesis of: N -methylated products via CO2fixation and primary carbamates from alcohols and urea
Haque, Najirul,Biswas, Surajit,Basu, Priyanka,Haque Biswas, Imdadul,Khatun, Resmin,Khan, Aslam,Islam, Sk Manirul
supporting information, p. 15446 - 15458 (2020/10/22)
In recent times, carbon dioxide fixation has received much attention for its potential application as an abundant C1 source and a range of important fine chemicals can be manufactured via this fixation. Here, a copper nanoparticle-decorated porous organic polymer-based (Cu-NPs@TzTa-POP) material was prepared by a simple in situ process. The catalyst was characterized by various techniques such as UV-vis spectra, FTIR spectra, HR-TEM, PXRD, N2 adsorption-desorption, TG-DTA, XPS, and AAS analysis. The synthesized heterogeneous catalyst showed excellent activity in an atmospheric carbon dioxide fixation reaction to produce N-methylated products from aromatic/heterocyclic amines in the presence of polymethyl-hydrosiloxane (PMHS) as the reducing agent at 80 °C within 12 h of the reaction. Through this catalytic N-methylation reaction, we obtained 98% yield of the product with turnover frequency ranging from 18 to 42 h-1. The catalyst is also very stable for the formation of primary carbamates from alcohols using the eco-friendly carbonylating agent, urea. Diverse alcohols (such as benzylic alcohols, phenols, heterocyclic alcohols, as well as aliphatic alcohols) showed much acceptance to this catalytic reaction and produced moderate to excellent yields of the respective carbamate products under ambient reaction conditions. Moreover, Cu-NPs@TzTa-POP is effortlessly recyclable and reusable without the extensive loss of active copper metal centres for many catalytic rounds (up to six catalytic rounds were examined).
Lignin-fueled photoelectrochemical platform for light-driven redox biotransformation
Boonmongkolras, Passarut,Choi, Eun-Gyu,Han, Seunghyun,Kim, Jinhyun,Kim, Kayoung,Kim, Yong Hwan,Lee, Sahng Ha,Lee, Yang Woo,Park, Chan Beum,Shin, Byungha,Trang, Nguyen Vu Thien,Wang, Ding
supporting information, p. 5151 - 5160 (2020/08/25)
The valorization of lignin has significant potential in producing commodity chemicals and fuels from renewable resources. However, the catalytic degradation of lignin is kinetically challenging and often requires noble metal catalysts to be used under harsh and toxic conditions. Here, we report the bias-free, solar reformation of lignin coupled with redox biotransformation in a tandem structure of a BiVO4 photoanode and perovskite photovoltaic. The tandem structure compensates for the potential gap between lignin oxidation and biocatalytic reduction through artificial Z-schematic absorption. We found that the BiVO4-catalyzed photoelectrochemical oxidation of lignin facilitated the fragmentation of higher molecular weight lignin into smaller carboxylated aliphatic and aromatic acids. Lignin oxidation induced photocurrent generation at the photoanode, which enabled efficient electroenzymatic reactions at the cathode. This study successfully demonstrates the oxidative valorization of lignin as well as biocatalytic reductions (e.g., CO2-to-formate and α-ketoglutarate-to-l-glutamate) in an unbiased biocatalytic PEC platform, which provides a new strategic approach for photo-biocatalysis using naturally abundant renewable resources.
N-Alkylation of N-trimethylsilyl derivatives of lactams, amides, and imides with alkyl sulfonates
Baukov, Yu. I.,Kramarova, E. P.,Negrebetsky, Vad. V.,Shagina, A. D.,Shipov, A. G.,Tarasenko, D. V.
, p. 398 - 400 (2020/04/15)
The reaction of N-trimethylsilyl derivatives of amides and imides with alkyl sulfonates on heating affords the corresponding N-alkyl derivatives and trimethylsilyl sulfonates.
One-pot synthesis of: N -methylpyrrolidine (NMPD) using Cu- and Ni-modified ZSM-5 as an efficient catalyst
Long, Yan,Wang, Peixue,Fei, Yuqing,Zhou, Dawei,Liu, Shimin,Deng, Youquan
, p. 141 - 148 (2019/01/11)
In this study, a green, efficient and low-cost process for the synthesis of N-methylpyrrolidine (NMPD) from 1,4-butanediol (BDO) and methylamine (MA) via a one-pot method was developed. Under the optimized reaction conditions, more than 90% yield of NMPD was achieved over a Cu and Ni modified ZSM-5 catalyst. The catalyst could be reused for several runs retaining a satisfactory catalytic performance, and the scale-up operation showed the potential of industrial application. Characterizations of BET, XPS, XRD, TEM, SEM, H2-TPR and NH3-TPD were conducted for the developed composite catalyst, which suggested that Cu2O and NiO were the main species on the support. Meanwhile, it was found that the H2 atmosphere, the high dispersion of metal oxides and the synergic effect between Cu and Ni species on ZSM-5 contributed to the excellent catalytic performance. Furthermore, a possible mechanism based on a borrowing-hydrogen process was also proposed.
Facile Preparation of N -Alkyl-2-pyrrolidones in a Continuous-Flow Microreactor
Zhou, Feng,Zhang, Boyu,Liu, Hongchen,Wen, Zhenghui,Wang, Kejun,Chen, Guangwen
, p. 504 - 511 (2018/04/27)
N-Alkyl-2-pyrrolidones have been widely used in the petrochemical industry, the agricultural chemical industry, electronic materials, etc. The distinct advantages of using N-alkyl-2-pyrrolidones as solvents or reaction media make them particularly important. A continuous-flow microreactor was exploited for the preparation of N-methyl-2-pyrrolidone (NMP) and N-ethyl-2-pyrrolidone (NEP) in a highly controlled and safe manner; thus, its use improved the efficiency of the process. Various conditions (temperature, residence time, molar ratio of amine to γ-butyrolactone (GBL), GBL concentration, water content, and presence of H3BO3 catalyst) were investigated to improve the synthesis of NMP/NEP. A microreactor was employed for the conversion of GBL to NMP and NEP, and the yields reached 94.7% for NMP and 93.9% for NEP under the optimized conditions. Furthermore, a kinetic model based on the reaction mechanism was proposed to guide the design and optimization of the synthesis of NMP/NEP.
AN IMPROVED PROCESS FOR THE SELECTIVE PRODUCTION OF N-METHYL-2-PYRROLIDONE (NMP)
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Page/Page column 10-11, (2017/02/28)
This invention relates to an improved process for the selective production of N-methyl pyrrolidone (NMP) from gamma-butyrolactone and monomethyl amine preferably in aqueous form in the presence of a catalyst under comparatively milder conditions than the processes well known in the prior art of literature. The process is economically viable as it provides higher yield and selectivity for NMP which reduces the cost of separation of NMP from GBL. The catalyst shows good recyclability without significant loss in catalytic activity and no frequent regeneration is required.
A N - methyl pyrrolidone continuous preparation method (by machine translation)
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Paragraph 0019; 0020; 0021, (2017/06/19)
The invention relates to a N - methyl pyrrolidone continuous preparation method, the method includes the steps of: (1) the pre-reaction and dehydration unit: γ - butyrolactone with methylamine aqueous solution mixed at room temperature after the pre-reaction, off part of the water does not participate in the reaction, thereby obtaining a reaction intermediate product; (2) high-temperature reaction unit: in the middle of the reaction product is added to the aqueous solution of methylamine, by heating, the boost to enter in a high-pressure reactor, a condensation reaction, condensation reaction to obtain the NMP; (3) product separation unit: reaction to obtain the high temperature and high pressure condensation reaction solution, after cooling, after dropping into the separation device, to get rid of moisture and residual methylamine, then, refining, NMP products obtained. The invention pre-removing methylamine aqueous solution with most of the water, preventing the large amount of water involved in the follow-up reaction, reduces the energy consumption of the NMP preparation process, reduces the volume of the use of the reactor, the reactor amplifying technique solves the difficult. (by machine translation)
