Ortho-phenylene diamines

Interesting examples of intramolecular oxidative amination have recently been reported. Permanganate oxidation of the arylhydra-zones of 3-formyl-1-methylquinoxalinium salts leads to pyrazoloquinox-alinium salts (Scheme 24) (02MC68). The reactive a-position in the quinoxalium ring makes the addition of the hydrazone nitrogen easily possible. Oxidation of a DMSO solution of the condensation product of 2-formylquinoxaline with ortho-phenylene diamine... 

One route is by reaction between ortho phenylene diamine and a carboxylic group (or a carbonyl group in oxidising media)... 

Treatment of aryl(aroyl)pyruvic acid ester metal chelates with ortho-phenylene-diamine and ethylenediamine is accompanied by an attack at the a-ketoester fragment, forming quinoxalones and piperazinones, respectively (95ZOR266, 99JFC(96)87) (Scheme 60). 

The reactions of butoxy(trifluoromethyl)enone 111 with 1,2-diamines (ortho-phenylene diamine and 1,2-ethylenediamine) lead to 1,5-diazepines 112 and 113 with ort/zo-aminophenol or ortho-aminothiophenol, the products are 1,5-oxazepines or... 

Normal day vernalized Optical density Ortho-dinitrobenzene Ortho-phenylene diamine High energy phosphate bond p- Chloromercurihenzolc acid Phosphoglyceric acid Phenazine methosulphate Parts per million rad... 

In our initial studies ( ), we examined several series of cured resins using ortho and meta isomers of phenylene diamine. p-Phenylenediamlne weis not considered for stu< due to its known ceurclnog lc nature. As shown in Table I, o-phenylenediamine (OPD) used edone was found to impart inferior properties to the crosslinked epoxy resin. We subject the poor performance of OPD is attributable to intramolecular hydrogai bonding, as shown below ... 

Abbreviations ODA = ortho dispersant index, BAPP = butyl acetate poly propylene, PDMA = poly dimethyl acrylate, and PDA = phenylene diamine. 

Following the same rationale, the Cl sequence can also be applied to the synthesis of seven-membered heteroazepines. Thus, upon CIR of electron-deficient (hetero) aryl halides 11 and (hetero)aryl propargyl alcohols 12, and subsequent addition of orf/io-phenylene diamines 50 or ortho-zmmo thiophenols 52, 2,4-di(hetero)aryl substituted 2,3-dihydro benzo[b][l,4]diazepines 90 or di(hetero)aryl substituted 2,3-dihydro benzo[h][l,4]thiazepines 91 can be obtained in a consecutive three-component reaction in moderate to good yields (Scheme 49) [242, 243]. 

Certain nuclear substituents ortho to a newly formed diazonium group may interact to form a cyclic structure with or without retention of the nitrogen atoms. Such is the case in the diazotization of o-phenylene-diamine in aqueous solution, the product being 1,2,3-benzotriazole (81%). If the ortho substituent is an activated methyl group, an indazole is formed. Hydroxyl groups ortho or para to the diazonium group may interact to form internal condensation products called diazo oxides. These compounds may also form in the reaction of halo- and nitro-substituted aminophenols. 

Tainter ML, James M, Vandeventer W. Comparative edemic actions of ortho meta and para-phenylene diamines in different species. Arch int Pharmacodyn 1929 36 152-162. 

A number of wholly aromatic polyamides based on substituted m and - phenylene diamines and isophthaloyl and terephthaloyl chloride were prepared and evaluated for 01 and char. The effect of having chlorine substituents ortho to the amine function was unusual in that large increases in 01 were obtained for the aramids with retention of high levels of char comparable to that of the unsubstituted aramids. Since all the chlorine was removed upon heating, a decrease in char yield was expected. An increased char yield indicated unexpected condensed phase reactions at high temperature. 

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