Synthesis of unsaturated diketones and δ2-pyrazoline derivatives from terephthalaldehyde

,-Unsaturated diketones were obtained by the condensation of terephthalaldehyde with aromatic and heterocyclic methyl ketones. The reaction of the diketones with phenyl-hydrazine gave 1,4-bis(1-phenyl-3-aryl-²-pyrazolin-5-yl)benzenes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1094–1096, August, 1971.     

Synthesis of unsaturated diketones and derivatives of Δ 2-pyrazoline based on 1, 4-diacetylbenzene

By means of the crotonic condensation of 1,4-diacetylbenzene with various aromatic and heterocyclic aldehydes, thirteen , -unsaturated diketones (diarylidene-1,4-diacetylbenzenes) were synthesized. The majority of these compounds are characterized by means of their bis(2,4-dinitrophenylhydrazones), the absorption maxima of which were determined in a solution of chloroform. By means of the interaction between diarylidene-1,4-diacetylbenzenes and phenylhydrazine hydrochloride, ten 1,4-bis(1-phenyl-5-R- ²-pyrazolinyl-3) benzenes were obtained which possess a bright green or blue luminescence.     

Synthesis of some acylated 2-pyrazoline and chalcone derivatives

α-Haloesters containing the chalcone structure and α-haloamides containing the pyrazoline ring have been synthesized by reaction of substituted hydroxy chalcones and pyrazoline derivatives (prepared as reported elsewhere; J Chem 8(4):1574–1581, 2011) with chloroacetyl chloride in dry THF in the presence of Et₃N. The structures of the synthesized compounds were confirmed by IR, ¹H NMR, and (for some compounds) ¹³C NMR spectroscopy.     

Synthesis of unsaturated δ-amino ketones containing a macrocyclic fragment

Conclusions A number of dienic mono--dimethylamino ketones, containing a macrocylic fragment, was synthesized by the condensation of 1,1,3-trimethoxy-3-dimethylaminopropane and-dimethylaminoacrolein acetal aminal with macrocylic ketones. We were unable to obtain polyenic bis-,-dimethylamino ketones, containing a macrocyclic fragment, by this route.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1373–1376, June, 1980.The authors express their gratitude to S. Z. Taits and E. S. Balenkova for supplying the macroeyclic ketones.     

Synthesis of pyrazolidine, 1-pyrazoline, 2-pyrazoline derivatives by selenium-induced cyclization of homoallylhydrazines

The PhSeBr-induced cyclization of N′-but-3-en-1-yl ethoxycarbonylhydrazines 1, phenylhydrazines 2 and dimethylhydrazines 3 has been studied. A 5-exo-trig ring closure occurred in each case and phenylselanylmethyl-pyrazolidines 4, 2-pyrazolines 5 and 10, 1-pyrazolines 8 and pyrazolidinium bromides 11 were synthesized. Radical deselenenylation has allowed the preparation of 5-methylpyrazolidines 12 and 5-methyl-2-pyrazolines 13 and 14. Decomposition of the dibromoselenuranes derived from 2-pyrazolines 5 and 10 afforded bromomethyl derivatives. With 1-phenyl-2-pyrazolines 10, an electrophilic p-halogenation of the phenyl nucleus was observed.     

Synthesis of chalcone analogs and derivatives of 2-pyrazoline from 3-formylindole

By the crotonic condensation in an alkaline medium of 3-formylindole with various aromatic and heterocyclic methyl ketones, and also with cyclopentanone, cyclohexanone, and 1,4-diacetylbenzene, we have synthesized nineteen ,-unsaturated ketones. The majority of them were characterized as the 2,4-dinitrophenylhydrazones, the absorption maxima of which in chloroform are given. Some considerations are expressed concerning the reactivity of 3-formyl- and 3-acetylindoles. Ten 3-aryl-1-phenyl-5-(indol-3-yl)-2-pyrazolines and their analogs with a 3-heterocyclic residue have been synthesized by the reaction of 3-aryl-1-(indol-3-yl)propen-3-ones and the corresponding analogs with phenylhydrazine. Some of the compounds synthesized possess a bright luminescence.     

Synthesis of unsaturated ω-dimethylamino ketones

Conclusions We have examined the condensation of 1,1,3-trimethoxy-3-dimethylaminopropane with cyclic and heterocyclic ketones and with enaminoketones; we have synthesized a series of unsaturated-dimethylamino and,-bis(dimethylamino) ketones, which the PMR spectra indicate as having the trans configuration of the methine protons and to exist as the S-trans conformers about the, -bond.Translated from Izvestiya Akademii Nauk SSSR, No. 1, pp. 116–122, January, 1978.     

One-pot syntheses of 2-pyrazoline derivatives

Hydrazinediium dithiocyanate and α,β-unsaturated ketones give in one-pot reactions 1-thiocarbamoyl-2-pyrazolines and 1-formyl-2-pyrazolines. The syntheses of pyridine-2-thiones, pyrimidine-2-thiones and bicyclo[2.2.2]octan-2-ones from ammonium thiocyanates and ketones by analogous procedures are reviewed. The mechanisms of the ring formations are discussed. Crystal structure analyses of a 1-thiocarbamoyl- and a 1-formyl-2-pyrazoline are given.     

Synthetic studies on teleocidin II. Synthesis of indole derivatives containing the same substituent to teleocidin bat 6- and 7-positions of indole nucleus.

The same substituent to teleocidin B at 6- and 7-positions of indole nucleus was introduced via intramolecular cyclization and oxidative cleavage of CN bond at 1-position starting from simple indole.     

Synthesis of substituted hydroxymethylene diphosphonic acids and their derivatives containing unsaturated fragments

Russian Journal of General Chemistry -     

Synthesis of alkyl indole derivatives

Condensation of arylamines with α-halogenoketone afforded the intermediate anilino-ketones which on direct cyclization furnished the corresponding alkylindoles. Synthesis of 2,3,5-trimethyl-4,7-dimethoxyindole (5a) and 2,3,6-trimethyl-7-methoxyindole (5b) is described. Earlier (1) synthesis of 2,3-dimethyl-4,7-dimethoxyindole and 1,2,3-trimethyl-4,7-dimethoxy-indole is reported.     

Synthesis of fused-tricyclic indole derivatives through an acid-promoted skeletal rearrangement

We developed a novel method for synthesizing fused-tricyclic indole derivatives with a 3-aminomethyl indole motif through a reaction cascade involving ipso-Friedel–Crafts alkylation of phenols, rearomatization of the spirocyclohexadienone unit, and iso-Pictet–Spengler reaction. Using TFA as an acid promoter, six-, seven-, and eight-membered ring-fused indoles were obtained in 31–99% yield.     

Synthesis of unsaturated ketones of the thiophene series

A number of unsaturated ketones containing a thiophene ring were obtained by the crotonic condensation of 2-thienyl-substituted carbonyl compounds with acetylenic ketones and aldehydes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1345–1347, October, 1971.     

Synthesis of indole derivatives via isocyanides

Fast and convenient approaches to the indole nucleus from isocyanides are reviewed as a means for the tailored preparation of conveniently functionalized indoles by using the unique reactivity of isocyanides in one-pot multicomponent and cascade reactions.     

Synthesis of α, β-unsaturated diketones and derivatives of 2-pyrazoline from 2, 5-diformylthiophene

The crotonic condensation of 2, 5-diformylthiophene with various aromatic and heterocyclic methyl ketones has given 15 , -unsaturated diketones. By the reaction of the latter with phenylhydrazine, ten 2, 5-di(1-phenyl-3-R-²-pyrazolin-5-yl)thiophenes possessing a bright blue-violet or green luminescence have been synthesized.     

Synthesis of an optically active unsaturated silicohydrocarbon containing an asymmetric silicon atom

Summary Starting with vinyltriethoxysilane, we were the first to obtain optically active dextrorotatory and levorotatory isomers of an unsaturated silicohydrocarbon, namely, of vinylphenyl--naphthylsilane.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 387–389, February, 1965