Simple Method for the Preparation of 1,3-Dithiol-2-one and 1,3-Dithiol-2-thione

Abstract

The reaction of diisopropyl xanthogen and thio-diisopropyl xanthogen disulfide with alkynes furnished 1,3-dithiol-2-one and 1,3-dithiol-2-thione.     

7-Bromo-5-phenyl-1,2-dihydro-3H-1,3,5-benztriazepin-2-one

7-Bromo-5-phenyl-1,2-dihydro-3H-1,4-benztriazepin-2-one was obtained by thermolysis of the syn-4-phenylsemicarbazone of 2-aminobenzophenone. Its molecular and crystal structure were established by X-ray crystallography. The nature of the hydrogen bonds between molecules of the compound in solution and in the crystalline state was determined by IR spectroscopy and X-ray crystallography.     

Molecular-crystal structure of 5-methyl-1,2-dihydro-3H-1,4-benzodiazepin-2-one

5-Methyl-1,2-dihydro-3H-1,4-benzodiazepin-2-one, which is an antagonist of 5-aryl-1,2-dihydro-3H-1,4-benzodiazepin-2-ones, was subjected to a complete x-ray diffraction study. The crystals have monoclinic syngony witha = 11.456(5), b = 8.195(3), c = 9.257(4) Å, = 93.10(3) °, and space group P2₁/b. The nonplanar molecules (with a boat conformation) form cyclic dimers by means of NH...O hydrogen bonds (2.937 Å) in the vicinity of the center of symmetry (0, 0, 1/2). Replacement of the phenyl ring in the 5 position by a less bulky methyl group does not lead to appreciable changes in the geometry and conformation of the heteroring. It is assumed that the substituent in the 5 position plays a role in determining the character of the pharmacological action of 1,4-benzodiazepines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 985–988, July, 1982.     

Alkylation of 3-Trifluoromethyl-1,2-dihydroquinoxalin-2-one

Russian Journal of Organic Chemistry - O and N centers of 3-trifluoromethyl-1,2-dihydroquinoxalin-2-one anion shows in reactions with haloalkanes an ambident nucleophilic character. The...     

Hydrolysis of 2-ethyl-1,2-oxaphospholan-5-one 2-oxide

Conclusions Hydrolysis of 2-ethyl-1,2-oxaphospholan-5-one 2-oxide proceeds via attack of water at both reactive centers, the phosphorus atom and the carbonyl carbon.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2314–2315, October, 1969.     

N-Substituted 4,5-dihydro-1,2-benzothiazepin-3-one 1,1-dioxide

The reaction of 2-carboethoxyethyl-4,5-dimethoxybenzene sulfochloride with substituted pyridines leads to the corresponding sulfonamides. The latter were hydrolysed to the acids, on which a general method for preparing a new ring system was based.     

Ozonolysis of 3-Caren-5-one

Cleavage by ozonolysis of a cyclic unsaturated ketone, 3-caren-5-one, was investigated under different conditions. The main reaction product is ketocaronic acid. A scheme of ketocaronic acid formation was suggested basing on kinetics of ozone reaction with 3-caren-5-one and thermal decomposition of peroxides.     

Synthesis of 2,2-Dimethyl-1,2-Dihydro-3H-pyrrol-3-one Preliminary Communication

The title compound 3g is obtained via two different routes, either in a multistep synthesis starting from 2-amino-2-methylpropionic acid (methylalanine) or by light-induced, oxidative dealkylation of the corresponding N-isopropyl derivative 3c .     

Preparation of 1,3-Dithiol-2-ones from 1,2-Bis-triisopropylsilanylsulfanyl Alkenes Under Mild Acidic Conditions

1,2-Bis-triisopropylsilanylsulfanyl alkenes are readily converted to 1,3-dithiol-2-ones with phosgene under very mild acidic conditions at room temperature.     

Synthesis of indazole derivatives from a N,N-disubstituted 2-halobenzoic hydrazide. Crystal structure of 1,2-pentamethylene-5-nitro-1,2-dihydro-3H-indazol-3-one

Thermal cyclization of the N,N-disubstituted 2-chlorobenzoic hydrazide 1 yields the 1,2-pentamethylene indazolone 5 , which structure is confirmed by X-ray crystallography. We suggest that the reaction proceeds through an N,N-alkyl shift in an initially formed indazolinium salt 2 . An intermediate 1-(5-chloropentyl)indazolol 4 has been isolated.     

Cycloaddition of 4,5-Dihydrooxazol-5-one Derivatives to 4-Methylbenzene-1,2-dithiol

Reactions of 4,5-dihydrooxazol-5-one derivatives with 4-methylbenzene-1,2-dithiol in the presence of triethylamine includes nucleophilic attack by the thiol group on the carbonyl carbon atom in the oxazole ring, followed by opening of the latter and recyclization to 1,4-benzodithiine derivatives.__________From Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1067–1070.Original English Text Copyright © 2005 by Tikdari, Fozooni, Vazee, Hamidian.The original article was submitted in English.     

Thermal decomposition study of 2-methyl-1,2-oxaphospholan-5-one 2-oxide

2-Methyl-1,2-oxaphospholan-5-one 2-oxide (OP) is useful in a wide range of flame-retarded compositions. It is a thermally stable substance which, in inert atmosphere, looses weight at 200 °C on dynamic heating, leaving a solid residue, the amount of which is sensitive to the presence of moisture. Due to the reactive PO bond, the thermal stability of OP can be increased by reaction with amines or alcohols and it can be introduced into a variety of plastics. Upon pyrolysis at 450 °C, OP volatilizes and decomposes, producing CO₂, low-chain hydrogencarbons, aliphatic and aliphatic-aromatic phosphine oxides and a black deposit, where polymeric phosphine oxides and phosphorus acid anhydrides were detected. Mechanism to explain the occurrence of the different products is proposed. Based on these data the condensed- and vapor-phase fire retardant mode of action of OP appear to be feasible.