O-3-Xylidine

Physical Form. Liquid, except o-4-xylidine is a solid... 

All except o-4 -xylidine are Liquids above 20. d 0.97-0.99, and bp between 213° and 226. They are sparingly sol in water, sol in alcohol and form more or Less sol salts with the strong mineral acids. 

Auwors, Ercklentz, Ann., 1898, 302,113. 5>Bromo-o-4-xylidine 5-Bromo-4-amino-o-xylene)... 

If either the o- or -position is occupied, only one isomer is obtained transformation to the mefo-position does not occur. This is a standard method of preparation of acyl-amino-ketones, or by a further hydrolysis of amino-ketones. The tendency, illustrated in this reaction, of groups to wander from the amino group to the nucleus, is also shown in previous reactions and in the preparation of aminoazobenzene from diazoamino-benzene (Preparation 456), of sulphanilic acid from aniline sulphate (Preparation 292), of o- and p-chloroacetanilides from acetochloranilide (Preparation 328), of o- and p-toluidine from methylaniline hydrochloride, and of 1 2 4-aminodimethylbenzene (2 4-xylidine) from dimethylaniline hydrochloride. 

Nitroxylenes are especially important because 4-amino-o-xylene (xylidine), formed from 4-nitro-o-xylene (4-o-NX) upon reduction, is used as a starting material for the production of riboflavin. Nitration of o-xylene by the conventional mixed acid method gives a mixture of 4-o-NX 31-55% and 3-o-NX 45-69 %. 

L = o-toluidine, o-anisidine, o-phenetidine, 3,4-xylidine L = o-phenylenediamine, 4Me-L L = thiazole L = N-n-butyl-imidazole... 

SYNS 1-AMINO-2.4-DIMETHYLBENZENE 4-AJMINO-l,3-DIMETHYLBENZENE 4-AMINO-3-METHYLTOLUENE 4-AMINO-l,3-XYLENE 2,4-DIMETHYLANILINE 2,4-DIMETHYLBENZENAMINE 2,4-DIMETHYLPHEiNYLAMINE 2-METHYL-p-TOLUIDINE 4-METHYL-o-TOLUIDINE 2,4-XYLIDENE (MAK) m-XYLIDINE m-4-XYLIDINE... 

Riboflavin or vitamin B, is obtained entirely by synthesis and its usage and role is predominantly as a vitamin rather than as a permitted colourant. The synthesis by Karrer was later improved by Tischler and proceeds from 3,4-xylidine (available through the nitration of o-xylene and reduction of the product), the Schiff s base of which with D-ribose is catalytically reduced. Benzenediazonium chloride is coupled with the hydrogenation product and the resultant azo compound is then condensed with barbituric acid in acetic acid (with loss of aniline) to give the final product. The process is illustrated in Scheme 28. 

Amino-o-toluene. See 3,4-Xylidine a-Aminotoluene. See N-Benzylamine m-Aminotoluene. See m-Toluidine o-Aminotoluene. See o-Toluidine p-Aminotoluene. See p-Toluidine 2-Aminotoluene hydrochloride. See o-Toluidine... 

The nitration of o-xylene at around 30 °C and separation of the product isomers by distillation and crystallization yields 3,4-dimethylnitrobenzene, which is transformed into 3,4-xylidine by catalytic reduction. 

S-Ethyl perhydroazepine-l-thiocarboxylate, see Molinate Ethyl 3-phertylcarbamoyloxyphertylcarbamate, see Desmedipham 0-Ethyl S -pheryl ethyldithiophosphonate, see Fonofos 0-Ethyl S -pheryl ethylphosphonodithioate, see Fonofos 0-Ethyl phenyl / -nitrophenyl pherylphosphorothioate, see EPN 0-Ethyl phenyl / -nitrophenyl thiophosphonate, see EPN Ethylphosphonodithioic acid O-ethyl S -pher rl ester, see Fonofos A-(l-Ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine, see Pendimethalin A-(l-Ethylpropyl)-2,6-dinitro-3,4-xylidine, see Pendimethalin Ethyl pyrophosphate, see Tetraethyl pyrophosphate... 

Xylidine Ethylaniline o-Phenetidine p-Phenetidine Ethyl fumarate Ethyl maleate Methyl heptenone Ethyl succinate... 

Xylidine o-Phenetidine Ethyl fumarate Ethyl succinate Propyl oxalate Caprylic acid Octyl alcohol... 

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