Application of the "Fries Like" Rearrangement Using ZnCl 2 for the Synthesis of 6-Acyl-2(3H)-benzothiazolones

In this work we report another method of acylation on the 6-position of the 2(3H)-benzothiazolone ring with Fries-like rearrangement catalyzed by zinc chloride instead of aluminium chloride and 3-acyl-2(3H)-benzothiazolones derivatives as starting materials. This method is advantagous in regard to other acylation methods as it requires only three equivalents of ZnCl 2 to produce 6-acyl-derivatives with yields of 82-94%.     

Study of the Acylation Reaction of 2(3H)-Benzothiazolones in the Mixture of ZnCl 2 -DMF

The use of polyphosphoric acid and the complex AlCl 3 -DMF in 6-acylation of 2(3H)-benzothiazolones previously have been reported. Instead of the frequently used AlCl 3 as a catalyst in the Friedl-Crafts reactions, we conducted the acylation of 2(3H)-benzothiazones using zinc chloride as a catalyst in DMF as solvent and acid chlorides or anhydrides as acylating agents.     

New Method of Synthesis of 2-Amino-4(5H)-oxothiophenes

A new method is proposed for the synthesis of 2-amino-4(5H)-oxothiophenes with aryl and hetaryl substituents in position 3 of the molecule by the acylation of aryl- and 2-azahetarylacetonitriles with mercaptoacetic acid ethyl ester.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 202–205, February, 2005.     

Selective amination of the mucohalic acid derivatives

An efficient synthesis of 4,5-diamino-3-halofuran-2(5H)-ones has been developed based on a sequential acylation and bisamination of mucohalic acids. The β-and γ-amination products have also been prepared with high regioselectivity. This reaction shows some advantages in terms of its simple operation and readily available but highly functionalized starting material. All products gave satisfactory IR, 1H NMR, 13C NMR and HRMS.     

Novel synthesis of 2-amino-3-hetaryl-4(5H)-oxothiophenes

3-Cyano-3-hetaryl-2-oxopropyl thioacetates were obtained by the acylation of hetarylacetonitriles with acetylmercaptoacetyl chloride. Their reaction with amines led to the formation of 2-amino-3-hetaryl-4(H)-oxothiophenes. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 680–685, May, 2006.     

Acylation of 2-azahetarylacetonitriles with (acetylthio)acetyl and α-(acetylthio)-propionyl chlorides. Production of 5-amino-4-hetarylthiophen-3(2H)-ones

3-Cyano-3-hetaryl-2-oxopropyl-and 3-cyano-3-hetaryl-1-methyl-2-oxopropyl ethanethioates were obtained by the acylation of 2-azahetarylacetonitriles with (acetylthio)acetyl and α-(acetylthio)propionyl chlorides respectively. They are deacetylated by the action of amines and undergo cyclization with the formation of 5-amino-4-hetarylthiophen-2(2H)-ones. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1314–1319, September, 2006.     

(S)-(4-溴-2-甲苯)(3-甲基吗啉)甲酮的合成

以(S)-2-氨基丙醇和氯乙酰氯为起始原料,经酰化和环合反应制得(S)-5-甲基吗啉-3-酮（4）; 4经还原制得(S)-3-甲基吗啉(5); 5与4-溴-2-甲基苯甲酸酰化缩合合成了(S)-(4-溴2-甲基苯基)(3-甲基吗啉)-甲酮,总收率57%,其结构经¹H NMR 和 ¹³C NMR确证。     

N-3-Oxoalkylamides and -Thioamides in the Synthesis of Heterocyclic Compounds. 7. Study of the Cyclization of N-(3-Oxoalkyl)amides of Tosylacetic Acid

Alkyl-substituted N-(3-oxoalkyl)amides of tosylacetic acid are cyclized under the action of bases with the formation of 3-tosyl-3,6-dihydropyridin-2(1H)-ones. In the presence of a phenyl substituent at position C₍₁₎ of the 3-oxoalkyl chain the reaction proceeds with the formation of 2-pyridones. The principles influencing the regiodirection of cyclization are explained.     

A facile synthesis of novel unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl)acetamidines

<正>A series of novel unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl) acetamidines was synthesized by reacting ethyl(1H)-N-(4-oxo-2-phenylquinazolin-3(4H)-y1)ethanimidoate(2) and suitable reactive aromatic amines.Structures' determination of the synthesized compounds was carried out using spectroscopic techniques including IR,~1H NMR,and mass spectrometry. Structural effects on reactivity were also studied.     

Recent advances and perspectives on the synthesis and C–H bond functionalization of quinoxalin-2(1H)-one

Abstract

Over the past few decades, quinoxalin-2(1H)-one derivatives are serving as active components in diverse families of drugs such as antimicrobial, anticancer, antithrombotic agents and protein kinase inhibitor. Previously, significant attention has been marked for its synthesis and recent years have also observed an upsurge in the modification of this scaffold as well as its functionalization. This review (2008–2020) focused on selective C–H bond functionalization namely arylation, amination, acylation, amidation, alkylation, benzylation, alkoxycarbonylation, cyanoalkylation and phosphorylation etc. at C-3 position of quinoxalin-2(1H)-one. Additionally, alternative complimentary route (radical cyclization protocol) for its synthesis part is well elaborated herein. We also briefly summarized the mechanistic pathway of the C–H bond functionalization approach.     

The Reactions of 6-(tert-Butyl)-3-hydrazino-1,2,4-triazin-5(2H)-one with Carbonyl Compounds

The reaction of 6-(tert-butyl)-3-hydrazino-1,2,4-triazin-5(2H)-one with acetone and benzaldehyde yields the corresponding hydrazones. In the presence of thionyl chloride the benzaldehyde hydrazone is converted to 3-(tert-butyl)-6-phenyl-1,2,4-triazolo[4,3-b]-1,2,4-triazin-2(1H)-one and this can also be formed via the acylation of the starting hydrazinotriazinone using benzoyl chloride.     

水合乙酸锌脱水反应的动力学

用等温热重法和非等温热重法研究了Zn(CH3COO)2 *2H2O的脱水反应.在61.1、 62.8、 66.2、 69.9℃下的等温热重数据,由等转化率下的lnt=E/RT+ln[g(α)/A]进行拟合,确定了活化能的大小;升温速率为10℃/min的非等温热重曲线显示, Zn(CH3COO)2 *2H2O的脱水反应发生在71～102℃间,其数据通过Doyle-Zsako法进行拟合,以线性相关系数为判据,并结合等温热分析拟合结果,得到该脱水反应的积分动力学模式函数g(α)=[-ln(1-α)]2/3、活化能E=100.8 kJ/mol、指前因子ln(A/s-1)=36.09、动力学补偿效应方程为lnA=0.3339E+2.010.     

Synthesis and Properties of 7-Acetyl-8-aryl-9-cyano-3-hydroxy-6-methyl-3,4-dihydro-2H,8H-pyrido[2,1-<Emphasis Type="Italic">b</Emphasis>][1,3]thiazines

7-Acetyl-8-aryl-2-(1-chloro-2-hydroxy-3-propyl)thio-9-cyano-6-methyl-1,4-dihydropyridines were obtained by treatment of 1,4-dihydropyridine-2(3H)-thiones with epichlorohydrin in the presence of sodium bicarbonate. When treated with NaOMe, these compounds are readily intramolecularly alkylated with formation of 7-acetyl-8-aryl-3-hydroxy-9-cyano-6-methyl-3,4-dihydro-2H,8H-pyrido[2,1-b]-[1,3]thiazines. We have studied amination of 2-(1-chloro-2-hydroxy-3-propyl)thio-1,4-dihydropyridines and acylation of 3-hydroxy-3,4-dihydro-2H,8H-pyrido[2,1-b][1,3]thiazines. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1394–1399, September, 2005.     

The Synthesis of 3-(2'-Hydroxybutyl) isobenzofuran-1 (3H)-one

l（3H】．Isobenzoturans（Dhthalldes】werereDortedtoexhibitawiderangeofbiologicalactivities．Forexample,3－n－butylphthallde（NB）exhibitsantlasthmatlc’,antlconvuls－ant“actlvltles．PenEandZhouhavestudiedonthemetabolismofNBPInrats‘．Theyfoundthat...     

Isomers and [2,3]-Sila-wittig Rearrangement of [（Allyloxy）silyl]lithium Silylenoid in the Gas Phase and THF Solvent

Theoretical calculations of the [2,3]-sila-wittig rearrangement of isomers of [（allyloxy）silyl]lithium （C3H5O）HzSiLi have been performed in the gas phase and THF solvent using the G3MP2B3 method. Seven isomers of silylenoid （C3H5O）H2SiLi, 1-7, are found. The [2,3]-silawittig rearrangement paths are followed using two isomers, 2 and 4, to yield the transition states as well as the products. In the transition state, the silicon center functions as a nucleophile and the aUyl as an electrophile. The interaction between the silicon and allylic sites leads to the formation of SiC（3） bond and the break of O-C（1） bond. Finally, the （allylsilyl）oxylithium （C3H5）H2SiOLi is obtained. The rearrangement paths are confirmed by the intrinsic reaction coordinate （IRC） calculations. The rearrangement mechanisms of reactions of 2 and 4 are similar, and the latter reaction is more favored in the gas phase and THF solvent. Also, the solvent effects are analyzed in this work.     

Isomers and [2,3]-Sila-wittig Rearrangement of [(Allyloxy)sily]lithium Silylenoid in the Gas Phase and THF Solvent

Theoretical calculations of the [2,3]-sila-wittig rearrangement of isomers of [(allyl-oxy)silyl]lithium (C3H50)H2SiLi have been performed in the gas phase and THF solvent using theG3MP2B3 method.Seven isomers of silylenoid (C3H5O)H2SiLi, 1～7, are found.The [2,3]-sila-wittig rearrangement paths are followed using two isomers, 2 and 4, to yield the transition states as well as the products.In the transition state, the silicon center functions as a nucleophile and the allyl as an electrophile.The interaction between the silicon and allylic sites leads to the formation of Si-C[3] bond and the break of O-C[1] bond.Finally, the (allylsilyl)oxylithium (C3H5)H2SiOLi is obtained.The rearrangement paths are confirmed by the intrinsic reaction coordinate (IRC)calculations.The rearrangement mechanisms of reactions of 2 and 4 are similar, and the latter reaction is more favored in the gas phase and THF solvent.Also, the solvent effects are analyzed in this work.     

Synthesis of 2-(ethylsulfanyl)aniline derivatives through the unexpected ring opening of N-substituted-2(3H)-benzothiazolones

The decarbalkoxylations of disubstituted geminal diesters by water–DMSO with added salts (KCN or NaCN) is a convenient preparative route leading to the corresponding monoesters. Herein, we described an efficient and very simple methodology for the preparation of 2-(ethylsulfanyl)aniline derivatives through the unexpected ring opening of the corresponding N-substituted-2(3H)-benzothiazolones in the presence of disubstituted geminal diester, KCN, and water–DMSO.     

Low-temperature heat capacities and thermodynamic properties of rare-earth triisothiocyanate hydrates (Ⅲ)——Sm(NCS)_3·6H_2O,Gd(NCS)_3·6H_2O,Yb(NCS)_3·6H_2O and Y(NCS)_3·6H_2O

The heat capacities of four RE isothiocyanate hydrates,Sm( NCS)3 6H2O,Gd( NCS)3 6H2O,Yb(NCS)3 6H2O and Y( NCS)3 6H2O,have been measured from 13 to 300 K with a fully-automated adiabatic calorimeter No obvious thermal anomaly was observed for the above-mentioned compounds in the experimental tem-peiatnre ranges.The polynomial equations for calculating the heat capacities of the four compounds in the range of 13-300K were obtained by the least-squares fitting based on the experimental Cp data.The Cp values below 13 K were estimated by using the Debye-Einstem heat capacity functions.The standard molar thermodynamic functions were calculated from 0 to 300 K.Gibbs energies of formation were also calculated.     

固相配位化学反应研究——ⅩⅩⅩⅩⅠ.[Co(NH_3)_5(H_2O)]Br_3,[Cr(NH_3)_5(H_2O)](NO_3)_3与无机盐KY(Y=Cl,Br,Ⅰ)的固相反应动力学研究

本文主要用气相色谱逸出气体分析方法,借助于红外、紫外可见漫反射谱等手段研究了[Co(NH_3)_5(H_2O)]Br_3、[Cr(NH_3)_5(H_2O)](NO_3)_3与无机盐KY(Y=Cl,Br,Ⅰ)的固相反应,计算了失水与失氨的动力学参数,发现第一步反应失水生成一取代中间产物,其活化能与外加阴离子无关,为S_N1过程。第二步失氨反应活化能与中心离子M以及取代基Y有关,当M=Co(Ⅲ)时,反应体系的失氨活化能大小有下列顺序:Cl>Br>Ⅰ(E值分别为187、155、98kJ·mol~(-1)),M=Cr(Ⅲ)时则正好相反:Ⅰ>Br>Cl(E值分别为213、146、79 kJ·mol~(-1))。     

Syntheses of Benzoxepinoquinolinone and Benzothiepinoquinolinone

l-Benzoxepino(3, 4-b)quinolin-l3(6H)-one and its halogen,alkyl, alkoxy derivatives Va'-d' and 1-benzothiepino(3,4-b}-quinolin- 13 ( 6H)-one Vf, and its alkyl derivatives Vg, weresynthesized through cyclization of 2-(substituted phenoxymethyl)-3-quinolinecarboxylic acids Va-d and 2-[ (un)substituted phen-ylthiomethyll-3-quinolinecarboxylic acids IVf-g in the presence ofpolyphosphoric acid.The acids IV were obtained from the corresponding ethyl-esters @ whcih were prepared through refluxing ethyl 2-bromo-methyl-3-quinolinecarboxylate(1) with substituted phenol or (un)substituted thiophenol in the presence of NaOEt.The compound Vg, was allowed to react with NBS, KaBH4, NH2OH-HCl to give compounds VII , VIII, and IX, respectively.The structures of 24 new compounds have been confirmed by elemental analysis, IR and 1H NMR.