Disulfide dealkylation

R = Et) yields, by the familiar Hugershoff cyclization,114 the substituted benzthiazole 128 and not the thiadiazolidine 129. In 1,5-dialkyl-aryl group suitable for benzthiazole formation, oxidation by iodine or bromine causes mainly S-dealkylation and subsequent formation of cyclic disulfides (126)137 in two cases, however, the formation of thiadiazolines (129 R = PhCH2, R = Me, R" = Me or Et and R = CH2=CHCH2, R=p-C6H4Me, R" = Me)137-138 as additional products in undisclosed yields, has been observed. 

Epoxidation and hydroxylation A-Dealkylation O-Dealkylation -Dealkylation -Oxidation A-Oxidation P-Oxidation Desulfuration Dehalogenation Nitro reduction Azo reduction Cytochrome P450 (CYP) Aflatoxin, aldrin, benzo[a]pyrene, bromobenzene, naphthalene Ethylmorphine, atrazine, dimethylnitrocarbamate, dimethylaniline p-Nitroanisole, chlorfenvinphos, codeine Methylmercaptan Thiobenzamide, phorate, endosulfan, methiocarb, chlorpromazine 2-Acetylaminofluorene Diethylphenylphosphine Parathion, fonofos, carbon disulfide CCLt, CllCb Nitrobenzene O-Aminoazotoluene Flavin-Containing Monooxygenase (FMO)... 

This benzophenone can be obtained by total dealkylation of its tetramethyl ether by the usual methods. This one (m.p. 109°) was prepared by reaction of dimeth-ylgentisic acid chloride (2,5-dimethoxybenzoyl chloride) with hydroquinone dimethyl ether (2,5-dimethoxybenzene) in the presence of aluminium chloride in carbon disulfide [409],... 

Preparation by dealkylation of 3,4-dichloro-4 -ethoxybenzophenone with aluminium chloride in refluxing carbon disulfide [903]. 

Preparation by dealkylation of 3-bromo-4 -ethoxy-benzophenone (SM) with hydrobromic acid (d = 1.49) in boiling acetic acid for 2 days. SM was obtained by action of m-bromobenzoyl chloride with phenetole in carbon disulfide in the presence of aluminium chloride at 55° (80%, m.p. 79°5). -Refer to Chem. Abstr., 17, 3497 (1923) . m.p. 171° Spectra (NA). 

Preparation by acylation of phenetole with m-nitrobenzoyl chloride in ethyl ether in the presence of alumininm chloride, then dealkylation of the 4-ethoxy-3 -nitrobenzophenone so formed with the same catalyst [141], in boiling carbon disulfide (60-70°) for 8 h [619] according to [139]. Preparation by Fries rearrangement of phenyl m-nitrobenzoate with alumininm chloride [897] without solvent at 120° or at 160° for 2 h (32%) [958]. 

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