Intermediate stages of the sulfohaloform reaction. Preparation of α-halosulfoxides and sulfinyl chlorides. Oxygen-transfer reactions

1977 ◽  
Vol 55 (3) ◽  
pp. 421-426 ◽  
Author(s):  
J. Stuart Grossert ◽  
William R. Hardstaff ◽  
Richard F. Langler

Details are provided of synthetic routes from dialkyl sulfides to both α-halosulfoxides and sulfinyl chlorides. In the case of the former, oxidation of α-halosulfides to the sulfoxide stage is achieved by chlorine in acetic acid containing controlled amounts of water. Sulfinyl chlorides are prepared by chlorination of α-polyhalosulfoxides in methylene chloride. During investigations into the details of the sulfohaloform reaction, a number of novel redox reactions involving oxygen transfer between sulfur species have been observed and these are presented. They include a reduction of a sulfoxide with thionyl chloride.

1964 ◽  
Vol 47 (5) ◽  
pp. 801-803 ◽  
Author(s):  
Peter John Andrellos ◽  
George R Reid

Abstract Three confirmatory tests have been devised to identify aflatoxin B±. Portions of the isolated toxin are treated with formic acid-thionyl chloride, acetic acid-thionyl chloride, and trifluoroacetic acid, respectively, and aliquots of the three fluorescent reaction products are spotted on thin-layer chromatography plates. Standards treated with each of the three reagents, plus an untreated standard, are spotted on the same plate, and after development the spots are compared under ultraviolet light.


ChemInform ◽  
2010 ◽  
Vol 22 (6) ◽  
pp. no-no
Author(s):  
F. A. DAVIS ◽  
M. S. HAQUE

1987 ◽  
Vol 40 (10) ◽  
pp. 1663 ◽  
Author(s):  
J Rosevear ◽  
JFK Wilshire

The reaction of several substituted o- nitronitrosobenzenes with O- and p- anisidine , and 2,4- dimethoxyaniline in acetic acid gives in good yield the corresponding enitroazobenzenes which are readily reduced with thiourea dioxide ( formamidinesulfinic acid) to the corresponding 2-(methoxypheny1)-2H-benzotriazoles, demethylation of which furnished the corresponding 2- (hydroxypheny1)-2H-benzotriazoles. Demethylation of the dimethoxy derivatives was best accomplished with boron tribromide in methylene chloride, the methoxy group located ortho to the benzotriazole ring being demethylated more readily than is the para-methoxy group. The reaction of enitroazobenzenes containing a methoxy group with hydrobromic acid in acetic acid results in cleavage of the azo bond and also partial bromination to give o- nitroaniline and some of its brominated derivatives.


2020 ◽  
Vol 66 (1) ◽  
pp. 23-29
Author(s):  
Octavia-Laura Moldovan ◽  
Diana-Nicoleta Brihan ◽  
Nicoleta Todoran ◽  
Aura Rusu

AbstractObjective: The compatibility of four binary active substances combinations adapalene – levofloxacin (ADP-LFX), adapalene – miconazole nitrate (ADP-MCZ), levofloxacin – meloxicam (LFX-MLX) and levofloxacin – miconazole nitrate (LFX-MCZ) was analysed to be comprised in new transdermal therapeutic systems. Also, the compatibility of selected active substances and four polymeric excipients (hydroxypropyl methyl-cellulose - HPMC 15000, hydroxypropyl methylcellulose - HPMC E5, ethyl cellulose - EC 10, and hydroxyethyl cellulose – HEC) was studied.Methods: Thin layer chromatographic method (TLC) and four selected mobile phases were used. On the plate (in situ) were obtained the binary combinations (active substances and active substance-polymer).Results: A good compatibility of ADP-LFX was found using ammonia : methanol : acetonitrile : methylene chloride 2:4:1:4 mobile phase. Using chloroform : acetone : glacial acetic acid 34:4:3 on the chromatogram of ADP-MCZ, only ADP spots appeared but without changes in the shape of the spots and Rf values. Any modifications of LFX and MLX spots (from LFX-MLX mixture) had been observed using toluene : glacial acetic acid : methanol 11:1:0.5 mobile phase, although LFX spots have remained on the baseline. Only LFX spots were visible from LFX-MLX and LFX-MCZ mixtures (ammonia : methanol : acetonitrile : methylene chloride 2:4:1:4 mobile phase). Distinctive spots were observed for ADP, LFX and MLX with variable results from no chemical interactions to limited chemical interactions when the compatibility with polymers was verified.Conclusions: ADP-LFX and LFX-MLX mixtures were found to be compatible. ADP with HPMC polymers and LFX with HPMC E5 and HEC had presented excellent compatibility; for the other binary combinations, different analytical methods will be necessary.


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