2-Aminobenzenethiol, reaction with

Aminobenzenethiol undergoes a Michael reaction with methyl 5,5-dimethyl-2-oxo-2,5-dihyd-rofuran-3-carboXylate (4) to give the adduct 5, which cyclizes to the tricyclic benzothiazepinone 6 under the influence of triethylamine hydrochloride.426... 

The pyrilium salt 30a was obtained from benzo-9-crown-3 in 29% yield in two steps by formylation with hexamine in the presence of CF3CO2H, followed by reaction with 2 equiv of acetophenone in the presence of POCI3 <2002JOC2065>. In the same manner, the Vilsmeier formylation of the /V-phenyl dithiazonine and the subsequent condensation reaction with 2-aminobenzenethiol resulted in substituted benzothiazole 43 in 38% yield < 1999J(P2)1273>. Benzo-9-crown-3 ether trimerizes in the presence of fed and aqueous sulfuric acid to produce tris-(9-crown-3)-triphenylene 28 in 25% yield <2001CJC195>. 

Aminobenzenethiol reacts with acetylenes and olefins to give 1,4-benzothiazines. Reaction with acetylene dicarboxylic acid and esters gives the 2-alkylidene derivates (35).79,80... 

Reactions of 2-aminobenzenethiol with a variety of other compounds provide the 1,4-benzothiazine ring system. An early report by Langlet claimed that the reaction with ethylene dibromide gave dihydro-1,4-benzothiazine (51).102 However, more recent work by Santacroce indicates the product is 2-methylbenzothiazole (52).94 However, 1,2-dichloroalkenes have been employed successfully by Kaul in the preparation of heterocyclic dye 53 having the l,4-benzothiazin-3-one ring.33... 

Dichloroquinoxaline has been converted into a number of polycyclic derivatives by reaction with o-disubstituted benzenes. Thus reaction with o-phenylenediamines gives tetraazanaphthacenes (17), and the corresponding reaction with 2,3-diaminoquinoxaline gives fluorubin derivatives (18). Quinoxalino[2,3-h]benzothiazine derivatives (19) result from the reaction of dichloroquinoxaline and o-aminobenzenethiol and... 

The increased resonance effect due to the presence of two nitro groups at both ortho positions and combined resonance and inductive effects enforced by one nitro and one halogen atom activate the Smiles rearrangement as well as the ring closure to such an extent that both processes take place instantaneously. However, the resonance elfect in 2,4-dinitrochlorobenzene is not so pronounced and its reaction with 2-aminobenzenethiol does not go in one step (88MI1). 

Aminobenzenethiol 80 undergoes a condensation reaction with cyclohexane-1, 3-diones 101 in DMSO yielding 2,3-dihydro-lH-phenothiazin-4(10H)-ones 103 (75JCS(CC)760) (Scheme 47), via intermediate 102 produced by the oxidation of 2-aminobenzenethiol to i is(o-aminophenyl) disulfide under the reaction conditions, followed by condensation with diones 101 to afford 2,3-dihydro-IH-phenothiazin-4(10H)-ones. 

Reaction of 2-aminobenzenethiol 22 with acetyl chloride 23 in water or without any solvent provides an environment-friendly route to benzo[[Pg.282]

The reaction of diketene with 2-aminobenzenethiol was reported to yield 4-methyl-l,5-benzo-thiazepin-2(3//)-one (1A),52 which exists in tautomeric equilibrium with the hydroxy form IB.53... 

The condensation of o-aminobenzenethiol with pyridine-2,6-dicarbaldehyde does not form the corresponding Schiff base but a polyheterocyclic compound which behaves as a tridentate ligand towards nickel(II).2365 In contrast the reaction of 2-(2-pyridyl)benzothiazoline with nickel(II) results in the opening of the heterocyclic ring and in the formation of a Schiff base ligand which coordinates to nickel(II) as a mononegative tridentate ligand.2366,2367... 

Reaction of the reduced ruthenium blue solution with thiols such as 2-aminobenzenethiol and 4-toluenethiol (LH) gives highly insoluble compounds of stoichiometry [Ru(L)2] which are prob-... 

A series of 2-trifluoromethyl and 2-difluoromethyl substituted benzothiazoles 30 has been synthesized by a one-pot reaction of trifluoroacetic acid and difluoroacetic acid, respectively, with 2-aminobenzenethiol <07TL3251 >. The reaction pathway presumably involves the imidolyl chloride intermediate 29, which undergoes intramolecular nucleophilic substitution by neighbouring thiol under basic conditions to give benzothiazole 30. 

The pyrolysis of a number of benzothiazolines, which were prepared by the reaction of o-aminobenzenethiols with ketones, have been investigated by Elderfield and McClenachan . The first-order rate coefficients were estimated by measure-... 

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