Π-deficient Compounds Research Articles

Oxidation–reduction and heterocyclization of the reactions of alkanedithiols with π-deficient compounds

ABSTRACTThe reaction of 1,2-ethanedithiol and 1,3-propanedithiol with π-deficient compounds afforded various oxidation–reduction and cyclized products under mild conditions. Heterocycles containing one sulfur atom (e.g. analogues of seriniquinone) were also obtained. The structures of the products were elucidated by NMR, IR, mass spectral data, and elemental analyses. The mechanisms were also discussed.

Carbamothioates in the synthesis of diaroyl sulfides; selectivity of diaroyl sulfides and their addition to acetylenic and ethylenic deficient compounds

Diaroyl sulfides were prepared in one-pot reaction from ethylenediamine and carbon disulfide, via reaction of in situ generated ethylene-bis-carbamodithioates with aroyl chlorides. The reaction of diaroyl sulfides with acetylenic and ethylenic π-deficient compounds such as dimethyl acetylenedicarboxylate, ethyl propiolate, (E)-1,4-diphenylbut-2-ene-1,4-dione and 1,4diphenylbut-2-yne-1,4-dione afforded the corresponding thionylated products. NMR spectroscopic data of the isolated products were discussed.

2-Aminothiophenol as building blocks for novel heterocycles

Herein, the chemistry of 2-aminothiophenol has been utilized in the synthesis of several interesting products such as oxidation and reaction with π-deficient compounds. On oxidizing 2-aminothiophenol by sodium hypochlorite furnishes 2-[(2-aminophenyl)-dithio]aniline. Treatment of the obtained product with acetyl chloride affords N-(2-[2-(acetylamino)-phenyl-disulphanyl)-phenyl]acetamide. Reaction of the former acetamide with POCl3 yields 2-methyl-1,3-benzothiazole. Moreover, (3,4,8,9)-dibenzo-2,7-dithia-5,10-diaza444propellane is formed on reacting the target 2-aminothiophenol with cyclohexane-1,2-dione, whereas its reactions with electron π-acceptors such as 2,3-dichloro-1,4-naphthoquinone (DCHNQ), 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), tetra-cyanoethylene (TCNE), and 1-(dicyanomethylen)acenaphthen-2-one yield various heterocycles.

Rhodanine in Fused-Heterocycles Syntheses

The reaction of 3-aminothiazolidine-2-thione-4-one (3-aminorhodanine, 1) with some π-deficient compounds afforded three types of products: bicyclic noncondensed derivatives such as bis(3-aminothiazole-2-thione-4-one), the condensation product 2-(3-amino-2-thioxothiazolo)-1,3-indanedione, as well as the fused heterocyclic compounds thioxothiazolo[3,4-c]oxadiazine, furo[2,3-b]thiazole, thiazolo[3,4-c]benzoxadiazine, and naphthoquinothiazolo[3,4-c]oxadiazine.

Base‐Catalyzed Synthesis of Novel Fused‐Imidazoles from N‐Vinyl‐1H‐imidazole.

Syntheses of various classes of fused-imidazoles are reported. The key to their successful synthesis depends on the reaction of N-vinyl-1H-imidazole with the π-deficient compounds under basic conditions. Reaction of the target imidazole with 1,1,2,2-tetracyanoethylene and dimethyl acetylenedicarboxylate afforded pyrrolo[1,2-a]imidazoles. On the other site, reaction of the target imidazole with 2-dicyanomethyleneindane-1,3-dione, 2,3-dicyano-1,4-naphthoquinone gave indanylimidazolo-[1,2-a]azepine and imidazolo[2,1-a]phenanthridine derivatives, respectively. Under basic reaction condition, various classes of imidazolo[2,l-a]isoquinolines were obtained by the reaction of N-vinyl-1H-imidazole with 2,3,5,6-tetrachloro-1,4-benzoquinone, 2,3-dichloro-1,4-naphthoquinone, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and 3,4,5,6-tetrachloro-1,2-benzoquinone.

Base Catalyzed Synthesis of Novel Fused-Imidazoles from N-Vinyl-1H-imidazole

Syntheses of various classes of fused-imidazoles are reported. The key to their successful synthesis depends on the reaction of N-vinyl-1H-imidazole with the π-deficient compounds under basic conditions. Reaction of the target imidazole with 1,1,2,2-tetracyanoethylene and dimethyl acetylenedicarboxylate afforded pyrrolo[1,2-a]imidazoles. On the other site, reaction of the target imidazole with 2-dicyanomethyleneindane-1,3-dione, 2,3-dicyano-1,4-naphthoquinone gave indanylimidazolo- [1,2-a]azepine and imidazolo[2,1-a]phenanthridine derivatives, respectively. Under basic reaction condition, various classes of imidazolo[2,1-a]isoquinolines were obtained by the reaction of N-vinyl- 1H-imidazole with 2,3,5,6-tetrachloro-1,4-benzoquinone, 2,3-dichloro-1,4-naphthoquinone, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and 3,4,5,6-tetrachloro-1,2-benzoquinone.

Synthesis of Some Functionalized 3-(4-Thioxo-3,4-dihydroquinazolin-2-YL) Acrylic Acid of Pharmaceutical Interest

3-(4-Thioxo-3,4-dihydroquinazolin-2-yl)acrylic acid 1 proved to be a convenient precursor for the synthesis of novel polyfunctional quinazoline derivatives of pharmaceutical interest via its treatment with some π-deficient compounds such as phenyl isocyanate and phenyl isothiocyanate. Also, S- and N-glucosidation of quinazoline has been achieved by treatment of 1 with glucopyranosyl bromide in alkaline medium. The behavior of 1 toward acrylonitrile (under Michael reaction condition), paraformaldehyde in the presence of secondary amines (under Mannich reaction condition) and sodium azide were investigated. Moreover, the peptidyl derivatives of quinazoline have been synthesized by condensation of 1 with α-amino acids via different routes. Some of the newly synthesized products were tested for their antimicrobial activities. The structure assignments are based on the analytical and spectroscopic results.

ChemInform Abstract: Chemistry of Alkylheterocyclic Aromatic π‐Deficient Compounds: A Novel Synthesis of Cinnolines.

ChemInformVolume 21, Issue 27 Heterocyclic Compounds ChemInform Abstract: Chemistry of Alkylheterocyclic Aromatic π-Deficient Compounds: A Novel Synthesis of Cinnolines. M. H. ELNAGDI, M. H. ELNAGDI Dep. Chem., Cairo Univ., Giza, EgyptSearch for more papers by this authorF. A. M. ABDUL-AAL, F. A. M. ABDUL-AAL Dep. Chem., Cairo Univ., Giza, EgyptSearch for more papers by this authorN. M. TAHA, N. M. TAHA Dep. Chem., Cairo Univ., Giza, EgyptSearch for more papers by this authorY. M. YASSIN, Y. M. YASSIN Dep. Chem., Cairo Univ., Giza, EgyptSearch for more papers by this author M. H. ELNAGDI, M. H. ELNAGDI Dep. Chem., Cairo Univ., Giza, EgyptSearch for more papers by this authorF. A. M. ABDUL-AAL, F. A. M. ABDUL-AAL Dep. Chem., Cairo Univ., Giza, EgyptSearch for more papers by this authorN. M. TAHA, N. M. TAHA Dep. Chem., Cairo Univ., Giza, EgyptSearch for more papers by this authorY. M. YASSIN, Y. M. YASSIN Dep. Chem., Cairo Univ., Giza, EgyptSearch for more papers by this author First published: July 3, 1990 https://doi.org/10.1002/chin.199027229Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume21, Issue27July 3, 1990 RelatedInformation

?,? Complexing capacities of heteroaromatic compounds (review)

The results of experimental studies and quantum-chemical calculations of pyrrole, methylpyridines, and azoles obtained in recent years make it possible to formulate the conditions for the manifestation of π-complexing capacities by π-deficient compounds and compounds of a similar nature, viz., blocking of the σ-donor center in the case of ortho substitution by alkyl groups and primary H or v bonding.