51-36-5Relevant academic research and scientific papers
Reactions of bisdiazonium salts derived from monosubstituted m-phenylenediamines with amides and nitriles of unsaturated acids under anionarylation conditions
Baranovskii,Yatsyuk,Vasilenko,Grishchuk
, p. 1821 - 1825 (2015)
Reactions of 5-carboxy and 4-methylphenylene-1,3-bisdiazonium tetrafluoroborates with amides and nitriles of acrylic and methacrylic acids in the presence of chloride, bromide, and thiocyanate anions proceed as anionarylation at one of the diazo groups and nucleophilic substitution at another one. With 4-methylphenylene- 1,3-bisdiazonium tetrafluoroborate as the arylating agent, the anionarylation and the Sandmeyer reaction occur involving para- and ortho-positioned diazo groups, respectively.
The lid domain of the MCP hydrolase DxnB2 contributes to the reactivity toward recalcitrant PCB metabolites
Ruzzini, Antonio C.,Bhowmik, Shiva,Yam, Katherine C.,Ghosh, Subhangi,Bolin, Jeffrey T.,Eltis, Lindsay D.
, p. 5685 - 5695 (2013)
DxnB2 and BphD are meta-cleavage product (MCP) hydrolases that catalyze C-C bond hydrolysis of the biphenyl metabolite 2-hydroxy-6-oxo-6-phenylhexa-2,4- dienoic acid (HOPDA). BphD is a bottleneck in the bacterial degradation of polychlorinated biphenyls (PCBs) by the Bph catabolic pathway due in part to inhibition by 3-Cl HOPDAs. By contrast, DxnB2 from Sphingomonas wittichii RW1 catalyzes the hydrolysis of 3-Cl HOPDAs more efficiently. X-ray crystallographic studies of the catalytically inactive S105A variant of DxnB2 complexed with 3-Cl HOPDA revealed a binding mode in which C1 through C6 of the dienoate are coplanar. The chlorine substituent is accommodated by a hydrophobic pocket that is larger than the homologous site in BphDLB400 from Burkholderia xenovorans LB400. The planar binding mode observed in the crystalline complex was consistent with the hyper- and hypsochromically shifted absorption spectra of 3-Cl and 3,9,11-triCl HOPDA, respectively, bound to S105A in solution. Moreover, ESred, an intermediate possessing a bathochromically shifted spectrum observed in the turnover of HOPDA, was not detected, suggesting that substrate destabilization was rate-limiting in the turnover of these PCB metabolites. Interestingly, electron density for the first α-helix of the lid domain was poorly defined in the dimeric DxnB2 structures, unlike in the tetrameric BphDLB400. Structural comparison of MCP hydrolases identified the NC-loop, connecting the lid to the α/β-hydrolase core domain, as a determinant in the oligomeric state and suggests its involvement in catalysis. Finally, an increased mobility of the DxnB2 lid may contribute to the enzyme's ability to hydrolyze PCB metabolites, highlighting how lid architecture contributes to substrate specificity in α/β-hydrolases.
Photo-induced deep aerobic oxidation of alkyl aromatics
Wang, Chang-Cheng,Zhang, Guo-Xiang,Zuo, Zhi-Wei,Zeng, Rong,Zhai, Dan-Dan,Liu, Feng,Shi, Zhang-Jie
, p. 1487 - 1492 (2021/07/10)
Oxidation is a major chemical process to produce oxygenated chemicals in both nature and the chemical industry. Presently, the industrial manufacture of benzoic acids and benzene polycarboxylic acids (BPCAs) is mainly based on the deep oxidation of polyalkyl benzene, which is somewhat suffering from environmental and economical disadvantage due to the formation of ozone-depleting MeBr and corrosion hazards of production equipment. In this report, photo-induced deep aerobic oxidation of (poly)alkyl benzene to benzene (poly)carboxylic acids was developed. CeCl3 was proved to be an efficient HAT (hydrogen atom transfer) catalyst in the presence of alcohol as both hydrogen and electron shuttle. Dioxygen (O2) was found as a sole terminal oxidant. In most cases, pure products were easily isolated by simple filtration, implying large-scale implementation advantages. The reaction provides an ideal protocol to produce valuable fine chemicals from naturally abundant petroleum feedstocks. [Figure not available: see fulltext.].
Synthesis of Dichlorobenzamide Derivatives: Crystal Structures of 3,5-Dichloro-N-(2-chlorophenyl)benzamide and 3,5-Dichloro-N-(4-chlorophenyl)benzamide
Zhang, Jun,Li, Yue,Wang, Bei,Jia, Ai-Quan,Zhang, Qian-Feng
, p. 108 - 115 (2020/02/18)
Abstract: Reactions of 3,5-dichlorobenzoyl chloride and arylamine compounds in N,N′-dimethylformamidesolution at 60 °C afforded a series of dichlorobenzamidederivatives 4–14 in good yields. These new compounds and accompanyingintermediates were characterized and confirmed by nuclear magneticresonance and infrared spectroscopy, of which structures of compounds 4and 6 were established by X-ray crystallography. Compound 4 crystallizesin triclinic space group Pī, with a = 5.047 (18), b = 10.28 (4), c = 13.36 (5) ?, α =107.59 (5)°, β = 93.55 (5)°, γ = 98.34 (5)°, and Z = 2. The unit cell of 6 has a monoclinic Pn symmetry with the cell parameters a = 9.581 (3), b = 12.217 (4), c = 11.072 (3) ?, β = 92.584 (4)°, and Z = 4. Graphic Abstract: A series of 3,5-dichlorobenzamide compounds were synthesized from reactions of arylamine compounds with 3,5-dichlorobenzoyl chloride, which was prepared from 3,5-dichlorobenzonitrile.[Figure not available: see fulltext.]
Milled Dry Ice as a C1 Source for the Carboxylation of Aryl Halides
O'Brien, Connor J.,Nicewicz, David A.
supporting information, p. 814 - 816 (2021/03/01)
The use of carbon dioxide as a C1 chemical feedstock remains an active field of research. Here we showcase the use of milled dry ice as a method to promote the availability of CO 2in a reaction solution, permitting practical synthesis of arylcarboxylic acids. Notably, the use of milled dry ice produces marked increases in yields relative to those obtained with gaseous CO 2, as previously reported in the literature.
Dimethyl sulfoxide-accelerated reductive deamination of aromatic amines with t-BuONO in tetrahydrofuran
Fang, Lu,Qi, Liang,Ye, Longfei,Pan, Zhentao,Luo, Wenjun,Ling, Fei,Zhong, Weihui
, p. 579 - 583 (2018/11/27)
An efficient method for the conversion of aryl amines into arenes by a one-pot reductive deamination has been achieved. It was found the reductive deamination using t-BuONO in tetrahydrofuran could be accelerated by dimethyl sulfoxide and provided the deamination products with good yields under mild conditions. A plausible mechanism is discussed.
Synthesis method of 2-amino-5-chloro-N,3-dimethylbenzamide
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, (2017/07/19)
The invention discloses a synthesis method of 2-amino-5-chloro-N,3-dimethylbenzamide, belonging to the technical field of organic chemical synthesis. The method comprises the following steps: carrying out oxidation under the catalytic actions of N-hydroxyphthalimide and cobalt acetylacetonate to generate benzoic acid, carrying out substitution reaction with chlorine gas to generate 3,5-dichlorobenzoic acid, shielding off 5- chlorine by using a shielding reagent, carrying out methyl substitution on the 5- chlorine by using a Grignard reagent to generate 3-methyl-5-chlorobenzoic acid, carrying out nitro-substitution on the 3-methyl-5-chlorobenzoic acid and nitric acid under the catalytic action of concentrated sulfuric acid to generate 2-nitro-3-methyl-5-chlorobenzoic acid, carrying out catalytic hydrogenation to reduce the nitro group into amino group, carrying out reaction under the actions of N,N'-diisopropylcarbodiimide and 1-hydroxybenztriazole to obtain an intermediate, and carrying out reaction on the intermediate and methylamine to obtain the 2-amino-5-chloro-N,3-dimethylbenzamide. The method is simple to operate, and obviously enhances the synthesis yield to 92% or above.
Method for estimating SN1 rate constants: Solvolytic reactivity of benzoates
Matic, Mirela,Denegri, Bernard,Kronja, Olga
supporting information, p. 8986 - 8998,13 (2012/12/12)
Nucleofugalities of pentafluorobenzoate (PFB) and 2,4,6-trifluorobenzoate (TFB) leaving groups have been derived from the solvolysis rate constants of X,Y-substituted benzhydryl PFBs and TFBs measured in a series of aqueous solvents, by applying the LFER equation: log k = sf(Ef + Nf). The heterolysis rate constants of dianisylmethyl PFB and TFB, and those determined for 10 more dianisylmethyl benzoates in aqueous ethanol, constitute a set of reference benzoates whose experimental ΔG ? have been correlated with the ΔH? (calculated by PCM quantum-chemical method) of the model epoxy ring formation. Because of the excellent correlation (r = 0.997), the method for calculating the nucleofugalities of substituted benzoate LGs have been established, ultimately providing a method for determination of the SN1 reactivity for any benzoate in a given solvent. Using the ΔG? vs ΔH? correlation, and taking sf based on similarity, the nucleofugality parameters for about 70 benzoates have been determined in 90%, 80%, and 70% aqueous ethanol. The calculated intrinsic barriers for substituted benzoate leaving groups show that substrates producing more stabilized LGs proceed over lower intrinsic barriers. Substituents on the phenyl ring affect the solvolysis rate of benzhydryl benzoates by both field and inductive effects.
SPIRO ISOXAZOLINE COMPOUNDS AS SSTR5 ANTAGONISTS
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Page/Page column 73; 74, (2011/12/04)
Substituted spirocyclic amines of structural formula (I) are selective antagonists of the somatostatin subtype receptor 5 (SSTR5) and are useful for the treatment, control or prevention of disorders responsive to antagonism of SSTR5, such as Type 2 diabetes, insulin resistance, lipid disorders, obesity, atherosclerosis, Metabolic Syndrome, depression, and anxiety.
Selective Mg insertion into substituted mono- and dichloro arenes in the presence of LiCl: A new preparation of boscalid
Dunst, Cora,Knochel, Paul
experimental part, p. 2064 - 2068 (2011/10/09)
The LiCl-mediated Mg insertion into polysubstituted aryl chlorides bearing up to three chloro substituents in ortho or meta position selectively leads to Grignard reagents which readily react with various electrophiles. As an application, we have developed a new formal synthesis of boscalid. Georg Thieme Verlag Stuttgart - New York.
