Furoxan, synthesis

The classical Wieland furoxan synthesis has been reinvestigated and this procedure applied to the preparation of 4-aryl-l,2,5-°xadiazole-3-yl derivatives 295 (Equation 61) <1996BML1993>. 

C NMR, 6, 398 molecular dimensions, 6, 397 tautomerism, 6, 404 Furoxan-3-carbohydra2ide intramolecular hydrogen bonding, 6, 396 Furoxan-3-carboxamide intramolecular hydrogen bonding, 6, 396 Furoxancarboxylic acids reactions, 6, 413 with nucleophiles, 6, 406 Furoxan-3,4-dicarbaldoxime synthesis, 6, 409 Furoxanoaaines fused... 

Furoxans, aroylamino-synthesis, 6, 414 Furoxans, aryl-reactions, 6, 412 Furoxans, arylamino-synthesis, 6, 414 Furoxans, arylaminobutyl-synthesis, 6, 423... 

Furoxans, bis[(acetoxyalkyl)carbonyl]-synthesis, 6, 421 Furoxans, bisarylsulfonyl-synthesis, 6, 423 Furoxans, bis(dialkylamino)-synthesis, 6, 414 Furoxans, butylhexynyl-synthesis, 6, 423 Furoxans, decamethylenering cleavage, 6, 405 Furoxans, diacyl-thermolysis, 6, 81 synthesis, 6, 442 Furoxans, diadamant-1-yl-ring cleavage, 6, 404 Furoxans, dialkoxycarbonyl-synthesis, 6, 423 Furoxans, dialkyl-synthesis, 6, 423 Furoxans, diaryl-ozonolysis, 6, 405 Furoxans, diaroyl-isoxazoles from, 6, 82 Furoxans, dibenzoyl-synthesis, 6, 423 Furoxans, diethoxycarbonyl-synthesis, 6, 423... 

Furoxans, diethyl-synthesis, 6, 423 Furoxans, dihalo-synthesis, 6, 423 Furoxans, dimethyl-NMR, 6, 397 O NMR, 6, 398 Furoxans, diphenylring cleavage, 6, 404 synthesis, 6, 423 Furoxans, hydroxy-reactions, 6, 414 Furoxans, mercapto-reaotions, 6, 414 Furoxans, nitro-as explosives, 6, 426 reactions, 6, 413-414 reduction, 6, 423 Furoxans, phenyl-reactions... 

Naphtho[l, 2-c]furazans electrophilic reactions, 6, 410 synthesis, 6, 418 Naphtho[l, 2-c]furoxans eleetrophilic reactions, 6, 410 3-Naphthoic acid, 2-hydroxy-l-(2-thiazolylazo)-analytical uses, 6, 328 Naphtho[ 1,2-h]imidazoles oxidation, 5, 405... 

A new general synthesis of 3-substituted derivatives has been reported (99MC13) (Scheme 9). Thus, the nitro group of furoxan 27 underwent a facile hydride replacement on treatment with NaBH4 in EtOH to give 3-monosubstituted furoxans 23. The result of this reaction is independent of the nature of R. 

Utilizing a common strategy for benzofuroxan synthesis, the related annulated furoxan 88 has been obtained from azidonitro compound 87 by heating in ethanol (83LA1901) (Scheme 38). 

A modihed Hantzsch synthesis has been utilized for the preparation of 1,4-dihydropyridines (Scheme 66). Thus, condensation of formylfurazans 116 with an acetoacetic ester and aminocrotonic acid ester in isopropanol at reflux led to 1,4-dihydropyridine derivatives 117 in about 70% yield (92AE921). Both isomeric furoxan aldehydes reacted in a similar way. 

Cavaleiro JAS, Tome Ja PC, Faustino MAP (2007) Synthesis of Glycoporphyrins. 7 179-248 Cerecetto H, Gonzalez M (2007) Benzofuroxan and Furoxan. Chemistry and Biology. 10 265-308... 

In the following chapter, Cerecetto and Gonzalez review the classical and most modern methods of the synthesis of benzofuroxan and furoxan deriva-... 

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