Di-p-tolyl disulfide

The enantiomorphs of a nonplanar disulfide sometimes become separated in crystals. Thus, diphenyl disulfide (43) and probably also di-p-tolyl disulfide (43) crystallize in enantiomorphous space groups with only one enantiomorph per unit cell, and so do barium tetrasulfide monohydrate (1) and sodium tetrathionate dihydrate (101). The same applies, of course, to L-cystine and other optically active disulfides. 

A mixture of di-p-tolyl disulfide, 3 moles diethyl malonate, and a soln. of 3 equivalents Na in abs. ethanol stirred 1 hr. at room temp. diethyl p-tolyl-thiomalonate. Y 96% conversion 76%. F. e. s. T. Fujisawa, K. Hata, and T. Kojima, Chem. Lett. 1973, 287. 

The first report of the photochemistry of a conjugated aromatic sulfoxide appears to be that of Kharasch and Khodair [32]. In a study more principally aimed at the sulfones, they showed that photolysis of diphenyl sulfoxide 5-H in benzene led to biphenyl 41 (53%), diphenyl sulfide (7%), and trace diphenyl-disulfide 45. Biphenyl was also the major product of diphenyl sulfone photolysis, and it was shown to arise from attack of the photochemically generated phenyl radical on solvent (benzene). The same mechanism was clearly implied for the sulfoxide. The disulfide presumably comes from secondary photolysis of the unobserved phenyl benzenesulfenate 42. (The formation of the sulfide is addressed below in the section of deoxygenation.) Later workers showed that pyridine could be tolylated by photolysis of di-p-tolyl sulfoxide 5-Me with a product distribution quite consistent with other radical phenylations [33]. 

In 1998, that company found that disulhdes such as diphenyl disulfide (87) and di-p-tolyl disnlfide (88) can be nsed as additives in small qnantities [107]. 

Measurements have been made by Koch (152, 153) on disulfides and diethyl, diphenyl, and di-2-benzthiazyl tetrasulfide and dicyclohexyl hexasulfide, and by the following authors on complete series R2S with n = 1 through 4 Baer and Carmack (12) for R = n-hexadecyl, Minoura for R = benzyl (176) and p-tolyl (177), and Haszeldine and Kidd (142) for R = trifluoromethyl. Harris (140) has recorded the spectra of the di-o-nitrophenyl mono- through pentasulfide series, Gorin and Dougherty (135) those of the di-n-alkyl disulfides from methyl through butyl, and dimethyl... 

Dibutyl xanthogen disulfide p,p -Dichlorobenzoyl peroxide Dicumyl peroxide Diisopropyl xanthogen polysulfide N,N-Dimethylcyclohexylamine dibutyidithiocarbamate Dipentamethylene thiuram hexasulfide Diphenylguanidine Diphenylguanidine phthalate N,N -Diphenylthiourea 4,4 -Dithiodimorpholine Di-o-tolyl guanidine Ethylenediamine carbamate Hexahydro-1,3,5-triethyl-s-triazine 2-Mercaptobenzothiazole 2-Mercaptothiazoline... 

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