Fused-s-triazino heterocycles IX. 1,3,4,6,9b-pentaazaphenalenes and 1,3,6,9b-tetraazaphenalenes: Amino and alkoxy derivatives

The trichloromethyl group served as a useful leaving group in nucleophilic displacement reactions by a variety of substituted amines and alcohols (the latter under base catalysis) on 2-trichloromethyl-5-methyl-1,3,4,6,9b-pentaazaphenalene ( 1a ) and 2-trichloromethyl-4-cyano-1,3,6,9b-tetraazaphenalene ( 2a ). The reaction conditions were mild and the yields of the corresponding 2-substituted amino and alkoxy derivatives were generally good.     

Fused s-triazino heterocycles. VIII. 1,3,4,6,9b-pentaazaphenalenes. Reactions of a methyl and bromomethyl side chain

Enhanced reactivity of the methyl group of 2-t-butyl-5-methyl-1,3,4,6,9b-pentaazaphenalene allowed acetic anhydride-catalyzed condensation reactions with several aromatic aldehydes, and base-catalyzed alkylation reactions with several alkyl halides to take place, albeit in low yields. Of the many nucleophiles tried, only salts of carboxylic acids, in the presence of 18-crown-6, were able to displace bromine from 2-(bromomethyl)-5-methyl-1,3,4,6,9b-pentaazaphenalene.     

Chlorination of 1,5-dimethylpyrazole

The chlorination of 1,5-dimethylpyrazole by gaseous chlorine in acetic acid in the presence of sodium acetate affords 1-methyl-3,4-dichloro-5-(dichloromethyl)pyrazole, which is subsequently converted to the 5-(trichloromethyl) derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 352–354, March, 1990.     

Fused s-triazino heterocycles. XV. 13H-4,6,7,13a,13c-pentaazabenzo[hi]chrysene, 13H-4,7,13a,13c-tetraazabenzo[hi]chrysene,and 7H-3,7,10,10b-tetraazacyclohepta[de]naphthalene,three new ring systems

The reaction of N-cyano-N′-(6-amino-2-pyridyl)acetamidine ( 5a ) and homophthalic anhydride followed by ring closure of the 2-[2-(carboxymethyl)phenyl]-5-methyl-1,3,4,6,9b-pentaazaphenalene intermediate ( 4a ) gave 5-methyl-13-oxo-13H-4,6,7,13a,13c-pentaazabenzo[hi]chrysene ( 8a ). An analogous series starting with 3-N-(6-amino-2-pyridyl)amino-2-cyano-2-butenenitrile ( 5b ) in place of 5a gave in two steps 5-methyl-13-oxo-13-H-4,7,13a,13c-tetraazabenzo[hi]chrysene-6-carbonitrile ( 8b ). Elemental analysis, ir and pmr spectra of 8a , 8b and several new model compounds aided in confirming the structures of 8a and 8b. The synthesis of one of these model compounds for 5b and phenylacetic anhydride led surprisingly to 2-methyl-9-phenyl-7H-3,7,-10,10b-tetraazacyclohepta[de]naphthalene ( 10 ) in addition to the expected 2-benzyl-4-cyano-5-methyl-1,3,-6,9b-tetraazaphenalene ( 7b ).     

Photochromic Dihetarylethenes: XX. Synthesis and Photochromic Properties of Dithienylethenes with a Fixed Conformation

>A procedure was developed for the synthesis of bis(2,5-dimethyl-3-thienyl)ethenes with partially fixed molecular conformation, and their photochromic properties in solution were studied. The structure of photochromic 1-(2,5-dimethyl-3-thienyl)-7,9-dimethyl-5,6-dihydrothieno[3',4' : 3,4]pyrido[1,2-c][1,3]oxazol-3-one, as well as of 1-(2,5-dimethyl-3-thienyl)-7,9-dimethylthieno[3',4' : 3,4]pyrido[1,2-c][1,3]oxazol-3-one possessing no photochromic properties, was determined by X-ray analysis.     

Electrochemical reduction of 4-methyl-4-(trichloromethyl)cyclohexa-2,5-dien-1-one

The properties of 4-methyl-4-(trichloromethyl)cyclohexa-2,5-dien-1-one which contains the trichloromethyl substituent at a quaternary carbon atom have been studied by cyclic voltammetry, rotating disk electrode voltammetry, and preparative electrolysis. Reductive dehalogenation involves initial two-electron reductive elimination of one of the geminal chlorine atoms followed by consecutive addition of proton, simultaneous elimination of the two residual halogen atoms to form carbene, and rearrangement of cyclohexadienone into the corresponding 4-methylcyclohepta-2,4,6-trien-1-one.     

2-Phenyl-5-(trichloromethyl)-1,3,4-oxadiazoles,A new class of antimalarial substances

An investigation of hybrids of 2,5-dimethyl-1,3,4-oxadiazole (I) and α,α,α,α',α',α'-hexachloro-p-xylene (Hetol®) (II) as potential antimalarial agents led to the synthesis of representative 2-phenyI-5-(trichloromethyl)-1,3,4-oxadiazoles (VIa-f, VIII-X) and related trichloromethyl 1,2,4-oxadiazole, 1,3,4-oxadiazoles, and 1,3,4-thiadiazole (VII, XIII-XV). Treatment of the appropriately substituted benzoic: acid hydrazides (IVa-f) with trichloroacetic anhydride afforded the intermediate 1-benzoyl-2-(triehloroacetyl)hydrazines (Va-f) which were cyclized to the desired 5-(chlorophenyl, tolyl, or α,α,α-trifluorotolyl)-2-(trichloromethyl)-1,3,4-oxadiazoles (VIa-f) (44–66%) in situ utilizing phosphorous oxychloride. Chlorination of the 5-tolyl-2-(trichloromethyl)-1,3,4-oxadiazoles (VId-f) afforded 2-(trichloromethyl)-5-(α,α,α-trichloro-m- and p-tolyl)-1,3,4-oxadiazole (VIII and IX) and 2-(α,α,α,α',α',α'-hexachloro-3,5-xylyl)-5-(trichloromethyl)-1,3,4-oxadiazole (X) in 23–56% yield. Each of the 2-phenyl-5-(trichloromethyl)-1,3,4-oxadiazoles (VIa-f, VIII-X) was active against Plasmodium berghei in mice when administered in single 160 or 640 mg./kg. subcutaneous doses or given orally by drug-diet for 6 days at doses of 29–336 mg./kg./day. The 2-(trichloromethyl)-5-(α,α,α-trichlorotolyl)-1,3,4-oxadiazoles (VIII-X) were the most active compounds prepared and exhibited activity against P. berghei comparable with Hetol®. Structure-activity relationships are discussed.     

Polyfunctional imidazoles: II. Synthesis and reactions with nucleophilic reagents of 1-substituted 2,4-dichloro-1<Emphasis Type="Italic">H</Emphasis>-imidazole-5-carbaldehydes

1-Alkyl(aryl)imidazolidine-2,4-diones reacted with Vilsmeier-Haack reagent affording 1-alkyl(aryl)-2,4-dichloro-1H-imidazole-5-carbaldehydes whose reactions with sodium azide, sodium alkoholates, with phenols, thiols, and secondary cycloalkylamines led to the substitution of chlorine in the position 2 of the imidazole ring. The reaction with primary amines resulted in the condensation products at the aldehyde group.     

Reactions of 3,5-di(tert-butyl)-1,2-benzoquinone with terminal acetylenes in the presence of phosphorus trichloride. ipso-Substitution of the tert-butyl group

The reactions of 3,5-di(tert-butyl)-1,2-benzoquinone with aryl-and alkylacetylenes in the presence of phosphorus trichloride afford 4-aryl(alkyl)-8-tert-butyl-2,6-dichloro-2-oxo-2H-benzo[e][1,2]oxaphosphinines as the major ipso-substitution products of the tert-butyl group by the chlorine atom. 4-Aryl(alkyl)-6,8-di(tert-butyl)-2,5-dichloro-2-oxo-and 4-aryl(alkyl)-6-tert-butyl-2,8-dichloro-2-oxo-2H-benzo[e][1,2]oxaphosphinines were obtained as the minor products. The structures of the stable representatives of this series were confirmed by X-ray diffraction. Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1836–1845, September, 2007.     

Carbazoledioxazines having long alkyl groups. 2. Synthesis of carbazoledioxazines with angular type structure

Carbazoledioxazines with an angular type structure (5,15-dialkyl-7,17-dialkyloxy-9,19-dichloro-5,15-dihydrodiindolo[2,3-c:2′,3′-n]triphenodioxazines) were selectively synthesized by electrochemical oxidative ring closure of precursors (2,5-bis(9-alkyl-2-alkyloxy-3-carbazolylamino)-3,6-dichloro-1,4-benzoquinones). The structure was confirmed by ¹H-nmr and other instrumental analyses. Their thermal properties and solubilities were investigated and were compared with those of carbazoledioxazines with a linear type structure.     

Carbazoledioxazines having long alkyl groups 1. Synthesis of carbazoledioxazines with linear type structure

Carbazoledioxazines with linear type structure (5,15-dialkyl-8,18-dichloro-5,15-dihydrodiindolo[3,2-b:-3′,2′-m]triphenodioxazine) were selectively synthesized by demethanolation ring closure of 2,5-bis(2-methoxy-9-alkyl-3-carbazolylamino)-3,6-dichloro-1,4-benzoquinone in a high boiling solvent. The structure has been confirmed by ¹H-nmr and X-ray crystallography.     

Studies on pyrazines. 13 . Chlorination of 1-hydroxy-2(1H)-pyrazinones with phosphoryl chloride. Formation of 2,5-dichloro-3-phenylpyrazine from 1-hydroxy-3-phenyl-2(1H)-pyrazinone

The chlorination of 1-hydroxy-3-phenyl-2(1H)-pyrazinone with phosphoryl chloride proceeded to 5-chloro-3-phenyl-2(H)-pyrazinone or 2,5-dichloro-3-phenylpyrazine on heating to elevated temperatures. To define the mechanism of the novel formation, reactions of the parent or methyl-substituted 1-hydroxy-2(1H)-pyraz-inones with the same reagent were investigated.     

Fused s-triazino heterocycles. X. Displacement reactions of 7,9-dibromo-2-tribromomethyl-5-trichloromethyl-1,3,4,6,9b-pentaazaphenalene and 7,9-dibromo-2,5-bis(tribromomethyl)- 1,3,4,6,9b-pentaazaphenalene

The preparation of 7, 9-dibromo-2-tribromomethyl-5-trichloromethyl-1, 3, 4, 6, 9b-pentaazaphenalene ( 1c ) and 7, 9-dibromo-2, 5-bis(tribromomethyl)-1, 3, 4, 6, 9b-pentaazaphenalene ( 1d ) is described. Reaction of 1c with various nucleophiles converted it to the corresponding 7, 9-dibromo-2, 5-bis-substituted derivatives, the tri-halomethyl groups serving as leaving groups. Displacement, first of one tribromomethyl group on 1d by pyrrolidine, and then by various nucleophiles on the remaining tribromomethyl group led to several mixed 2, 5-disubstituted derivatives.     

SOME CHLOROHYDROXYBENZENESULFONYL DERIVATIVES

Abstract

2,4-; 2,6-; 2,3-; 3,4-; 2,5-; and 3,5-dichlorophenols by reaction with chlorosulfonic acid were converted to the following substituted benzenesulfonyl chlorides: 3,5-dichloro-2-hydroxy-; 3,5-dichloro-4-hydroxy-; 2,3-dichloro-4-hydroxy-; 4,5-dichloro-2-hydroxy-; 2,5-dichloro-4-hydroxy-; and 2,6-dichloro-4-hydroxy-respectively. In addition o-chlorophenol gave 5-chloro-4-hydroxybenzene-1,3-bis-sulfonyl chloride. The various sulfonyl chlorides have been condensed with nucleophilic reagents, e.g. ammonia, amines, hydrazine, phenylhydrazine, N, N-dimethylhydrazine, and sodium azide. 3,5-Dichloro-2-hydroxybenzenesulfonyl azide has been reacted with norbornene, triphenylphosphine, dimethylsulfoxide, and cyclohexene. 3,5-Dichloro-2-hydroxybenzenesulfonyl chloride with phenylisocyanate gave the 2-(N-phenyl-carbamoyloxy) derivative which on heating gave a heterocyclic compound. The chlorohydroxybenzenesulfonyl derivatives are of interest as potential herbicides and their ir and nmr spectral characteristics are briefly discussed.     

Reactions of 2,3,5-trichloro-4,4-ethylenedioxy-2-cyclopentenone with some ambident nucleophiles. Sterically loaded functionalized 6-azabicyclo[3.1.0]hex-5-enes

2,3,5-Trichloro-4,4-ethylenedioxy-2-cyclopentenone reacted with sodium azide in tetrahydrofuran to give the expected 3-azido derivative which was converted into 1,3-dichloro-4,4-ethylenedioxy-6-azabicyclo-[3.1.0]hex-5-en-2-one and 3-amino-2,5-dichloro-4,4-ethylenedioxy-2-cyclopentenone on heating in chloroform. The reaction of 2,3,5-trichloro-4,4-ethylenedioxy-2-cyclopentenone with potassium thiocyanate, depending on the conditions, afforded the corresponding 3-thiocyanato derivative or symmetric sulfide. Treatment of the title compound with hydroxylamine resulted in opening of the dioxolane ring with simultaneous formation of oxime via replacement of chlorine at the neighboring sp ²-carbon atom.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 10, 2004, pp. 1569–1573.Original Russian Text Copyright © 2004 by Shavaleeva, Ivanova, Usmanova, Akhmetvaleev, Miftakhov.     

Synthesis of 1,2-dichlorotetrafluoro- and 1,2,4-trichlorotrifluorobenzenes

1,2-Dichlorotetrafluorobenzene was obtained by reactions of chlorine with 5,6,7,8-tetrafluoro-1,4-benzodioxane and with a mixture of 3,4,5,6-tetrafluorophthaloyl chloride and 3,3-dichloro-4,5,6,7-tetrafluorophthalide at 500–550°C. Pyrolysis of pure 3,4- and 2,5-dichlorotrifluorobenzenethiols, as well as of a mixture of 3,4-, 2,4-, and 2,5-dichlorotrifluorobenzenethiols, in the presence of chlorine at 400–415°C in a flow system gave difficultly accessible 1,2,4-trichlorotrifluorobenzene.     

Synthesis of some ω- (2,5-dichloro-3-thienyl)alkanoic acids and their intramolecular ring closure

The synthesis of 1-chloro-4,5,6,7-tetrahydrobenzo[c]-4-thiophenone and 1-chloro-5,6,7,8-tetrahydro-4H-cyclohepta[c]-4-thiophenone was accomplished by the cyclization of the acid chlorides of -(2,5-dichloro-3-thienyl)butyric acid and -(2,5-dichloro-3-thienyl)valeric acid, respectively, to 1,3-dichloro-4,5,6,7-tetrahydrobenzo[c]-4-thiophenone and 1,3-dichloro-5,6,7,8-tetrahydro-4H-cyclohepta[c]-4-thiophenone and by partial dehalogenation of the latter by heating with copper metal in propionic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1358–1360, October, 1971.     

Investigation of the reaction of 1-methyl-2,5-dichloro-3,4-diformylpyrrole with amines

The reaction of 1-methyl-2,5-dichloro-3,4-diformylpyrrole with amines of the aliphatic series leads to products of replacement of one chlorine atom. With aromatic amines the reaction takes place at one of the formyl groups to give aminals. The latter in the presence of excess amine readily give bisazomethines of 1-methyl-2-chloro-5-arylamino-3, 4-diformylpyrrole, which can also be obtained directly by the reaction of dichlorodiformylpyrrole with arylamines. It is shown that in this case one of the formyl groups and the adjacent chlorine atom react initially, after which the second formyl group reacts. The chlorine atom in bisazomethines of 1-methyl-2-chloro-5-arylamino-3,4-diformylpyrrole has high nucleophilic lability and is easily replaced by a hydroxy group or a piperidine residue.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1489–1493, November, 1981.     

Fused s-triazino heterocycles. XVI. 13H-1,3,7,8,12a, 13c-hexaazabenzo[de]naphthacene and 1,3,7,8,11b, 12,14,14d-octaazadibenzo[de,hi]naphthacene,two new ring systems

The reaction of 7,9-dibromo-5-tribromomethyl-2-t-butyl-4-cyano-1,3,6,9b-tetraazaphenalene ( 1a ) with 2-amino-5-picoline is shown to give 4,6-dibromo-2-t-butyl-13-imino-11-methyl-13H-1,3,7,8,12a,13c-hexaazabenzo[de]naphthacene ( 3 ) and the isomeric 7,9-dibromo-2-t-butyl-4-cyano-5N-(5-methyl-2-pyridyl)amino-1,3,-6,9b-tetraazaphenalene ( 2a ). A related annulation reaction of 7,9-dibromo-2-t-butyl-5-chloro-4-cyano-1,3,6,9b-tetraazaphenalene ( 1g ) with 2-amino-6-trimethylacetamidopyridine leads in two steps to 4,6-dibromo-2,13-di-t-butyl-1,3,7,8,11b,12,14,14d-octaazadibenzo[de,hi]naphthacene ( 4a ). The preparation of 1g , 5-azido-7,9-dibromo-2-t-butyl-4-cyano-1,3,6,9b-tetraazaphenalene ( 1c ) and the reaction of the latter with pyrrolidine leading to 7,9-dibromo-2-t-butyl-4-cyano-5-(1-pyrrolidino)-1,3,6,9b-tetraazaphenalene ( 1e ) are also reported. Attempted displacement of the azido-group on 1c by 2,6-diaminopyridine affords surprisingly 5-amino-7,9-dibromo-2-t-butyl-4-cyano-1,3,6,9b-tetraazaphenalene ( 1d ).     

The reaction of 2-substituted-4,5-dichloro-3(2H)-pyridazinones with alkoxides and alkylthiolates

The reaction of 2-substituted-4,5-dichloro-3(2H)-pyridazinones 1a-b with alkoxides and alkylthiolates was investigated. Regiospecific displacement of either the 4 or 5 chlorine atom could be achieved in most cases by appropriate selection of the reaction solvent.