5461-49-4Relevant academic research and scientific papers
Isomorphism of chiral ammonium salts Ph(All)N+Et(Me)X-·CHCl3
Kostyanovsky, Remir G.,Lyssenko, Konstantin A.,Krutius, Oleg N.,Kostyanovsky, Vasily R.
, p. 19 - 20 (2009)
The title ammonium salts (X = Br, I) were synthesized, the identity of crystal structures for them (space groups P212121, Z = 4) was found, spontaneous resolution of Ph(All)N+Et(Me)Br-·CHCl3 was performed, and the impossibility of replacement of the solvate molecule by CHBr3 or CH2Hal2 (Hal = Cl, Br, I) was demonstrated by 1H NMR and X-ray diffraction studies.
Olefin functionalized IPr.HCl monomer as well as preparation method and application thereof
-
Paragraph 0069-0073; 0075; 0078, (2021/06/21)
The invention relates to an olefin functionalized IPr.HCl monomer, a preparation method thereof, a method for preparing an N-heterocyclic carbene functionalized organic polymer (PS-IPr-x) by using the olefin functionalized IPr.HCl monomer, and application of the N-heterocyclic carbene functionalized organic polymer as a heterogeneous catalyst for catalyzing reduction N-formylation of carbon dioxide and amine. A heterogeneous catalyst is prepared by using cheap and easily available DVB as a polymerization cross-linking agent through an AIBN-initiated olefin polymerization method, and has the advantages of low preparation cost and simple preparation method. Meanwhile, the catalytic activity of the catalyst is obviously higher than that of reported catalysts, and the catalyst has a wide practical application prospect.
Catalyst-free photoinduced selective oxidative C(sp3)-C(sp3) bond cleavage in arylamines
Duan, Wentao,Lian, Qi,Wang, Songping,Wei, Wentao,Zhou, Jingwei
supporting information, p. 3261 - 3267 (2021/05/21)
Due to the directional nature of sp3-hybridized orbitals and the absence of π-orbitals, the oxidative cleavage of the kinetically and thermodynamically stable C(sp3)-C(sp3) bond is extremely difficult and remains scarcely explored. In this work, under the double argument of quantum mechanics (QM) computations and meticulous experiments on our well-designed C-C single bond cleavage mechanism, we discovered a means of photoinduced selective oxidative C(sp3)-C(sp3) bond cleavage in arylamines, easily achieved by simple visible light irradiation using O2as a benign oxidant under very mild conditions. The utility of our methodology was demonstrated by the C(sp3)-C(sp3) bond cleavage in morpholine/piperazine arylamines with excellent functional group tolerance. Importantly, our methodology is noteworthy, not only in that it does not require any catalysts, but also in that it provides valuable possibilities for the scalable functionalization of clinical drugs and natural products.
Method for exciting C-C bond fracture acylation and application
-
Paragraph 0034-0042; 0205-0213, (2021/07/21)
The invention provides a method for exciting C-C bond breakage acylation and application; the method comprises the following steps: mixing a compound with a structural formula shown in the specification with an organic solvent, and reacting in oxygen and
Study on the mild, rapid and selective difluorocarbene-mediated triclassification of iododifluoroacetophenone with secondary amines and tree model for product classification
Chen, Xiu-Ping,Han, Jie,Hu, Yin-Jie,Li, Yun-Fang,Wang, Xiang-Cong,Ran, Jian-Xiong,Wang, Zhong-Hua,Wu, Fan-Hong
, (2020/12/14)
Difluorocarbene is a very active and widely used intermediate in organic synthesis. In this work, a room temperature difluorocarbene-mediated triclassification reaction of iododifluoroacetophenone (2) and secondary amines with mild condition, short reaction time (only 10 min) and high selectivity had been studied, which produced one of the following three substances: N-CF2H derivatives (up to 87% yield), formamides (82–89% yield) or the recycled starting secondary amines. This phenomenon was related to the structural stability of the corresponding products. If unstable, it would be hydrolyzed to formamides first, and then further hydrolyzed to starting amines. Based on the geometric structure of the raw materials, the corresponding prediction tree model was established, which provided guidance for the further application of difluoromethylation of Vemurafenib (1ee) and AZD9291 (1ff).
A substituent- And temperature-controllable NHC-derived zwitterionic catalyst enables CO2upgrading for high-efficiency construction of formamides and benzimidazoles
Li, Hu,Li, Zhengyi,Wu, Hongguo,Yang, Song,Yu, Zhaozhuo,Zhang, Lilong,Zhu, Kaixun
supporting information, p. 5759 - 5765 (2021/08/23)
Chemocatalytic upgrading of the greenhouse gas CO2 to valuable chemicals and biofuels has attracted broad attention in recent years. Among the reported approaches, N-formylation of CO2 with an amine is of great significance due to its versatility in the construction of N-containing linear and cyclic skeletons. Herein, a stable N-heterocyclic carbene-carboxyl adduct (NHC-CO2) was facilely prepared and could be used as a recyclable zwitterionic catalyst for efficient CO2 reductive upgrading via either N-formylation or further coupling with cyclization under mild conditions (25 °C, 1 atm CO2) using hydrosilane as a hydrogen source. More than 30 different alkyl and aromatic amines could be transformed into the corresponding formamides or benzimidazoles with remarkable yields (74%-98%). The electronic effect of the introduced substituent on NHC-CO2 was found to evidently affect the thermostability and nucleophilicity of the zwitterionic catalyst, which is directly correlated with its catalytic activity. Moreover, NHC-CO2 could supply CO2 by in situ decarboxylation at a specific temperature that is dependent on the introduced substituent type. Experimental and computational studies showed that the carboxyl species on NHC-CO2 was not only a nucleophilic center, but also a C1 source which rapidly captures or substitutes ambient CO2 during hydrosilylation. In addition, a simple and green conceptual process was designed for the product purification and catalyst recycling, with a good feasibility for small-scale production.
Design of Lewis base functionalized ionic liquids for the N-formylation of amines with CO2 and hydrosilane: The cation effects
Li, Xiao-Ya,Fu, Hong-Chen,Liu, Xiao-Fang,Yang, Shu-Han,Chen, Kai-Hong,He, Liang-Nian
, p. 563 - 569 (2020/02/05)
A series of functionalized ionic liquids (ILs) were developed for the reductive functionalization of CO2 with amine and hydrosilane to afford formamides under mild conditions. It was found that 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)-based IL i.e. [DBUC12]Br showed high efficiency for the N-formylation reaction of amines without using any organic solvents or additives. Furthermore, control experiments suggested the cations with active hydrogen may weaken the nucleophilicity of anions through ion pairing interactions, thereby affecting the activation of hydrosilane. The reaction mechanism was then investigated by Density Functional Theory (DFT) calculations. This protocol represents a highly efficient and environmentally friendly example for catalytic conversion of CO2 into value-added chemicals such as formamide derivatives by employing DBU functionalized ILs.
Ligand-Enabled Ni-Al Bimetallic Catalysis for Nonchelated Dual C-H Annulation of Arylformamides and Alkynes
Luan, Yu-Xin,Wang, Yin-Xia,Ye, Mengchun,Zhang, Feng-Ping
supporting information, (2020/03/19)
A bifunctional secondary phosphine oxide (SPO) ligand-controlled method was developed for Ni-Al-catalyzed nonchelated dual C-H annulation of arylformamides with alkynes, providing a series of substituted amide-containing heterocycles in ≤97% yield. The SPO-bound bimetallic catalysis proved to be critical to the reaction efficiency.
Synthesis of silyl formates, formamides, and aldehydesviasolvent-free organocatalytic hydrosilylation of CO2
Ema, Tadashi,Hasegawa, Jun-Ya,Hiyoshi, Mahoko,Murata, Takumi,Ratanasak, Manussada
supporting information, p. 5783 - 5786 (2020/06/03)
Carbon dioxide (CO2) was used as a C1 source to prepare silyl formates, formamides, and aldehydes. Tetrabutylammonium acetate (TBAA) catalyzed the solvent-freeN-formylation of amines with CO2and hydrosilane to give formamides including Weinreb formamide, Me(MeO)NCHO, which was successively converted into aldehydes by one-pot reactions with Grignard reagents.
Selective: N-formylation/N-methylation of amines and N-formylation of amides and carbamates with carbon dioxide and hydrosilanes: Promotion of the basic counter anions of the zinc catalyst
Zhang, Qiao,Lin, Xiao-Tao,Fukaya, Norihisa,Fujitani, Tadahiro,Sato, Kazuhiko,Choi, Jun-Chul
supporting information, p. 8414 - 8422 (2020/12/29)
A catalyst composed of commercially available Zn(OAc)2 and 1,10-phenanthroline (phen) was effective in the N-formylation/N-methylation of amines using CO2 as the C1 source in the presence of hydrosilanes. An equimolar reaction of N-methylaniline with PhSiH3 under a CO2 atmosphere yielded the N-formylation product in 92% yield at 25 °C. Scale-up of the reaction using 10 mmol substrate was also successful in affording the desired product in 83% yield (1.1 g). This catalyst exhibits a high thermal stability and a turnover number (TON) of 385000 at 150 °C. In addition, the reaction of N-methylaniline in the presence of excess Ph2SiH2 produced N,N-dimethylaniline. Furthermore, our catalytic protocol was developed for the N-formylation of amides and carbamates, which have smaller pKa values and lower reactivities than the corresponding amines. The present Zn(OAc)2/phen catalyst was found to show versatility in the conversion of CO2 and amines into several functionalized organic chemicals under mild conditions. We propose that the basic counter anion (i.e., the acetate) of the catalyst activates both the Si-H and N-H bonds.
