81534-96-5

Upstream product

• 636-32-8 1,2,4,5-benzenetetrol 
• 81534-95-4 2,5-dibromo-3,6-dipropionamidohydroquinone 
• 81534-84-1 4,8-dibromo-2,6-diethylbenzo[1,2-d:4,5-d']bis(oxazole) 
• 81534-88-5 bromomethylbenzobis(ethyloxazole) 
• 81534-82-9 3,6-diamino-2,5-dibromo-1,4-hydroquinone 
• 27344-26-9 3,6-diamino-2,5-dibromo-1,4-benzoquinone 
• 488-48-2 tetrabromobenzoquinone 
• 98332-12-8 1-allyl-4-methyl-2,3:5,6-bis(cyclohexylidenedioxy)benzene 
• 98332-11-7 1,2:4,5-bis(cyclohexylidenedioxy)-3-methylbenzene 
• 182-86-5 dispirobis<1,3>dioxole-6',1''-cyclohexane> 
• 81534-90-9 allylmethylbenzobis(ethyloxazole) 
• 615-94-1 2,5-dihydroxy-1,4-benzoquinone 
• 81534-92-1 6-allyl-2,5-dihydroxy-3-methyl-1,4-benzoquinone 
• 77-78-1 dimethyl sulfate 

Downstream Products

• 98332-10-6 1-Benzyl-5-benzylamino-2,6-dimethyl-1H-indole-4,7-dione 
• 98332-09-3 6-allyl-2,5-bis(benzylamino)-3-methyl-1,4-benzoquinone 
• 98332-13-9 6-allyl-3,6-bis(allylamino)-3-methyl-1,4-benzoquinone 
• 81534-93-2 6-allyl-2,5-diamino-3-methyl-1,4-benzoquinone 

Relevant academic research and scientific papers

Oxidative Cyclization of Unsaturated Aminoquinones. Synthesis of Quinolinoquinones. Palladium-Catalyzed Synthesis of Pyrroloindoloquinones

2-Allyl-3,6-diamino-5-methyl-1,4-benzoquinone (1) underwent a facile oxidative cyclization to produce quinolinoquinone 3 in the presence of a variety of oxidizing agents, including palladium(II) salts.Chloranil was the most efficient oxidizing agent and produced 3 in high yield.Under hydrolysis conditions, (hydroxyethyl)benzobis(oxazole) 4 underwent a retroaldol reaction, followed by an aldehyde amine condensation and an electrocyclic cyclization to form quinolinoquinones.In contrast, 2-allyl-3,6-bis(benzylamino)-5-methyl-1,4-benzoquinone (13) underwent smooth, palladium(II)-catalyzed cyclization to form the corresponding indoloquinone.The corresponding bis(allylamino)benzoquinone 17 underwent a similar cyclization, followed by an olefin insertion reaction to form pyrroloindoloquinones 20 and 21.

Synthesis of 2,5-Disubstituted 3,6-Diamino-1,4-benzoquinones

A general synthetic approach to a wide variety of 2,5-disubstituted 3,6-diamino-1,4-benzoquinones was developed.Bromanil was diaminated with ammonia, and adjacent NH2 and OH groups were protected as benzoxazoles by treatment with a carboxylic acid chloride followed by a polyphosphate ester cyclization-dehydration.The resulting 2,5-dibromobenzobis(oxazoles) were monolithiated by halogen-metal exchange with n-butyllithium and then reacted with a variety of electrophiles.The remaining bromide was replaced in a similar fashion.Alternatively the second bromide was replaced by reaction with ? allylnickel halide complexes.The benzoxazole protecting group could be hydrolyzed with zinc(II) chloride/HCl-aqueous ethanol under an inert atmostphere.Air oxidation of the resulting hydroquinone under neutral conditions gave the desired 2,5-disubstituted 3,6-diamino-1,4-benzoquinone in good to excellent overall yield.This method was used to synthesize precursors to the basic ring system of the mitomycin antineoplastic antibiotics.Acid hydrolysis of the benzoxazole protecting group under oxidizing conditions resulted in the production of 2,5-disubstituted 3,6-dihydroxy-1,4-benzoquinone.Methylation followed by reaction with ammonia gave the desired diaminoquinone.