A NEW AND SHORT SYNTHESIS OF 7 H-BENZO[a]CYCLOHEPTEN-7-ONE AND SOME DERIVATIVES: OXIDATION OF 7-BROMO-5H-BENZO[a]CYCLOHEPTENE

Oxidation of 7-bromo-5H-benzo[a]cycloheptene with some oxidation reagents has been studied. Several 2,3- and 4,5-benzotropone derivatives has been obtained. The structures of the products were determined by ¹H-, ¹³C NMR data and chemical transformation.     

Catalyst free synthesis of 2-Aryl-2H-benzo[b][1,4]oxazines and 3-Aryl-2H-benzo[b][1,4]thiazin-2-ones: An ultrasonication-assisted strategy

An ultrasonication-assisted synthesis of 2-Aryl-2H-benzo[b][1,4]oxazines and 3-aryl-2H-benzo[b][1,4]thiazin-2-ones has been established by reacting phenacyl bromides with 2-aminophenol and 2-aminothiophenol, respectively. This approach fosters flexibility in generating a diverse range of 1,4-benzoxazines and 1,4-benzothiazinones under catalyst-free reaction conditions. Further scope toward the synthesis of rarely occurring bis-benzoxazine adduct has also been explored, which enabled us to propose the reaction mechanism.     

4-烯丙氧基吡啶-1-氧化物的合成及其重排反应的研究

在烯丙醇中用4-氯吡啶-1-氧化物与烯丙醇钠于温和的条件下作用,以很好的收率合成出4-烯丙氧基吡啶-1-氧化物,并在真空中研究了它的热重排。我们发现:除生成正常的克莱森重排产物3-烯丙基-4-羟基吡啶-1-氧化物外,另一重排产物是N-烯丙基-4-吡啶酮。     

2,4-Diaryl-2,3-dihydrobenzo[b][1,4]thiazepines

2,4-Diaryl-2,3-dihydrobenzo[b][1,4]thiazepines are obtained in a single stage from chalcones and ortho-aminothiophenol in the presence of triethylamine. The nature of the electronic transitions in their UV absorption spectra is discussed with the use of quantum-chemical methods. It was shown that the seven-membered ring does not invert in the range of temperatures between –80 and +140 °C and is in the boat form. The main initial event in the fragmentation of the molecules of the obtained compounds under electron impact is the formation of benzothiazole-containing radicalions. In an acidic medium 2,4-diphenyl-2,3-dihydrobenzo[b][1,4]thiazepine is hydrolyzed to 3-(2-aminophenylthio)-1,3-diphenyl-1-propanone, and in its reaction with 2,4-dinitrophenylhydrazine chalcone hydrazone and o-aminothiophenol are formed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1638–1642, December, 1983.     

SYNTHESIS AND CRYSTAL STRUCTURE OF[Li.4THF][GdCl_4·2THF]

GdCl_3 reacts with CH_3C_6H_4Li at a molar ratio of 2:1 in tetra-hydyofuran(THF)to yield an interesting compound [Li·4THF][GdCl_4·2THF];its X-ray crystal structure shows the molecule to be an ion-pair.     

Triphenylantimony(V) Catecholates Based on o-Quinones,Derivatives of Benzo[b][1,4]-Dioxines and Benzo[b][1,4]-Dioxepines

Russian Journal of Coordination Chemistry - New catecholate complexes of triphenylantimony(V), (Etgly-3,6-DBCat)SbPh3 (I), (Propgly-3,6-DBCat)SbPh3 (II), and (Cat-3,6-DBCat)SbPh3 (III), based on...     

SYNTHESIS OF NEW 2,3-UNSATURATED O-GLYCOSIDES THROUGH FERRIER REARRANGEMENT[1]

The synthesis of five new 2,3-unsaturated O-glycosides (3a—e) employing Ferrier's rearrangement with different catalysts, is reported.     

11-Substituted polyfluorodibenz[b,f][1,4]oxazepines

Tetrafluorodibenz[b,f][1,4]oxazepin-11-(10H)-ones have been synthesized and converted to 11-chloro and 11-piperidino substituted polyfluorodibenz[b,f][1,4]oxazepines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 539–542, April, 1989.     

2-烷基-1,3-丙二醇β-溴丙醛缩醛的合成及表征

2-烷基-1,3-丙二醇β-溴丙醛缩醛又名5-烷基-2-溴乙基-1,3-二氧六环(3),是合成含1,3-二氧六环的可断裂表面活性剂的中间体[1],这种表面活性剂在中性和碱性条件下很稳定,在酸性条件下易断环变成非表面活性剂,这样可克服在有机合成、分析化学以及研究胶束中的反应等使用普通表面活性剂时因存在令人讨厌的乳浊液而使产物难以分离的缺陷.因此,研究和开发这类表面活性剂,无论在理论上,还是在应用中都具有十分重要的意义.     

Furo[3,2-e]pyrrolo[1,2-α][1,4]diazepine and derivatives

The 5,10-dihydro-4H-furo[3,2-e]pyrrolo[1,2-α][1,4]diazepin-5-one ( 7 ) and furo[3,2-e]pyrrolo[1,2-α][1,4]diaze-pine ( 10 ) are synthesized from suitable isocyanates 3a,b in acetic acid. The reactivity of 10 (C- and N-alkyla-tion) is investigated.     

SYNTHESIS,NMR AND MOLECULAR MODELING STUDY OF 4,9a-DIARYL-9,9a-DIHYDRO 1H-[1,4]THIAZINO[4,3-a][1,3]BENZIMIDAZOLES

A series of substituted 4,9a-diaryl-9,9a-dihydro-1H-[1,4]thiazino[4,3-a][1,3]benzimidazoles was prepared in good yields from the reaction of bis(aroylmethyl) sulfides with ortho-phenylenediamine in glacial acetic acid under reflux and under microwave irradiation. Microwave irradiation is found to accelerate the reaction, besides giving better yield in the case of the thiazinobenzimidazoles with electron-withdrawing groups in the aryl rings than the thermal reaction.     

A NOVEL SYNTHESIS OF 2-SUBSTITUTED-4H-THIENO [2,3-d][1,3] OXAZIN-4-ONE AND 2,3-DISUBSTITUTED THIENO [2,3-d]PYRIMIDIN-4(3H)-ONE DERIVATIVES

Abstract

The synthesis of acetic 2-{[1-methyl-2-(4-oxo-5,6,7,8-tetrahydro-4H-benzo [4,5]-thieno [2,3-d] [1,3-oxazin-2-yl)ethylidene]amino}-4,5,6,7-tetrahydrohenzo[b]thiophene ?3-carboxylic acid anhydride 5 and 2-(oxopropyl)-5,6,7,8-tetrahydro-4H-benzo-[4,5] thieno[2,3-d][1,3]oxazin-4-one 7, has been achieved in three steps from ethyl 2-amino-4,5,6,7-tetrahydrobenzo(b]thiophene-3-carboxlate 1 via the reaction with ethyl acetoacetate followed by hydrolysis and acetic anhydride-induced cyclization. The 2-substituent in compound 5 has two functional groups i.e. active methylene and acid anhydride which are suitably located for intramolecular transformation. Thermal and/or base catalyzed intramolecular cyclization of 5 afforded 2-(4-acetoxy-(hydroxyl)-2-methyl-5,6,7,8-tetrahydrobenzo[4,5] thieno[2,3-b]pyridin-3-yl)-5,6,7,8- tetrahydro-4H-benzo[4,5]thieno[2,3-d] [1,3]oxazin-4-one 10 and 9 respectively. Treatment of 5 with hydrazine hydrate, aromatic and/or heterocyclic amines induced the same intramolecular cyclization with a concomitant oxazine-pyrimidine interconversion to give 3-amino(aryl or heteryl)-2-(4-hydroxy-5,6,7,8-tetrdhydrobenzo-[4,5]thieno[2,3-b]pyridin-3-yl)-3,4,5,6,7,8-hexahydrobenzo[4,5] thieno[2,3-d] pyrimid in-4-one 11–14 respectively.     

Darstellung und Kristallstruktur von β-[SeCl3][MoOCl4]

Preparation and Crystal Structure of β-[SeCl₃][MoOCl₄] The reaction of Se₄[MoOCl₄] and Te₄[MoOCl₄] with SOCl₂ as solvent at 150 °C and 80 °C yields [SeCl₃][MoOCl₄] and [TeCl₃][MoOCl₄] respectively within 3 to 6 days as yellow-brown, moisture-sensitive crystals. [TeCl₃][MoOCl₄] was obtained in the already known monoclinic form, while β-[SeCl₃][MoOCl₄] crystallizes in a new polymorphic triclinic form (P1¯, Z = 2, a = 752.7(2), b = 812.8(2), c = 956.9(3) pm, α = 92.55(3)°, β = 111.63(2)°, γ = 107.39(3)°). The structure contains centrosymmetric tetranuclear units ([SeCl₃]₂[Mo₂O₂Cl₈]) which are analogous to the entities found in the structure of [SCl₃][MoOCl₄]. The packing of the molecules in β-[SeCl₃][MoOCl₄] and [SCl₃][MoOCl₄] is distinctely different.     

Novel synthesis of spirocyclic-3,4-dihydro-2H-benzo[b][1,4]oxazine derivatives

A two-step procedure involving acid catalyzed ring opening of spirocyclic epoxides with 2-haloanilines and subsequent palladium-catalyzed intramolecular C–O bond formation to provide spirocyclic-3,4-dihydro-2H-benzo[b][1,4]oxazine derivatives is described.     

SYNTHESIS AND REACTIONS OF HALO DERIVATIVES OF 4-ISOPROPYL-2H-1,4-THIAZIN-3-ONE

Abstract

Reaction of 4-isopropyl-2H-1,4-thiazin-3-one 1 (R [dbnd] i-Pr) with N-chloro- and N-bromosuccinimide occurred exclusively at the 6-position to give 6-chloro and 6-bromo derivatives of 1 (R [dbnd] i-Pr), respectively, in high yield, in sharp contrast to the 2-aroyloxylation by benzoyl peroxide or m-chloroperbenzoic acid reported earlier.² Reaction of 1 (R [dbnd] i-Pr) with methanesulfonyl chloride in the presence of aluminum chloride afforded an addition compound, 4-isopropyl-5,6-dichloro-1,4-tetrahydrothiazin-3-one. The 2-chloro derivative 6 of 1 (R [dbnd] i-Pr) was successfully prepared by hydrolysis of the 2-m-chloroben-zoyloxy derivative of 1 (R [dbnd] i-Pr) followed by treatment with thionyl chloride. Derivative 6 reacted readily under mild conditions with water, alcohols, thiols, ammonia and amines to give various 2-substituted compounds of 1 (R [dbnd] i-Pr). With phenol as a nucleophile, 1 (R [dbnd] i-Pr) reacted exclusively at the para position. Reaction at carbon atoms also occurred with N,N-dimethylaniline and 2,6-xylidine.     

[4 + 2]-cycloaddition of alkyl vinyl ethers to 3-aroylpyrrolo-[2,1-c][1,4]benzoxazine-1,2,4-triones

Russian Journal of Organic Chemistry -