Diazepinones, rearrangement

Pyrazolo[3,4-d][l,2]diazepines synthesis, 7, 597 Pyrazolop, 4- 6][ 1,4]diazepines synthesis, 5, 272 Pyrazolo[l, 4]diazepinones as anticonvulsant, 1, 170 Pyrazolo[2,3-e]diazepinones synthesis, 5, 272 1 H-Pyrazolo[l,5-6]imidazoles synthesis, 6, 992 Pyrazolo[2,3-a]imidazoles biological activity, 6, 1024 Pyrazolo[2,3-c]imidazoles reactions, 6, 1041 synthesis, 6, 1047 Pyrazolo[2,3-imidazoles synthesis, 6, 991 Pyrazolo[3,2- njisoquinolines synthesis, 5, 339 Pyrazolop, 4-c]isoquinolines synthesis, 5, 273 Pyrazolonaphthyri dines synthesis, 5, 339 Pyrazolone, diazophotolysis, 5, 252 Pyrazolone, 4,4-dihalo-rearrangements, 5, 250 Pyrazolone, ethoxy-hydrazinolysis, 5, 253 Pyrazolone, 4-halo-... 

Fryer et al. have found that hcnzodiazepinones rearrange to isoindoles in high yield under a variety of conditions. The benzo-diazepinone (73), on treatment vuth sodium hydride in dimethyl formamide (DMF), gave the isoindolecarboxamide (74) in better than... 

Benzodiazepinones also undergo rearrangement to isoindoles when treated with acetic anhydride and pyridine (Py). The diazepinone (81), for instance, gives l-phenyl-3-acetylisoindole (82) under these conditions. The structure of the product was established in this case by comparison with (82) prepared by acetylation of 1-phenyl-isoindole. The rearrangement may be formally represented by a... 

On irradiation the diazepinone 7 rearranges to the bicyclic ketone 8 by a symmetry allowed disrotatory 4rc-electrocyclization.9 5... 

The pyrrole derivative of carbonyl azide 206 undergoes thermal Curtius rearrangement into isocyanate, which spontaneously cyclizes into pyrrolo-diazepinone 207 (Equation (27) (1991JHC1911)). 

New seven-membered diazepinone alkoxyamines 394 for nitroxide-mediated radical polymerization were prepared through the Beckmann rearrangement (equation 159). 

Diazabicyclo[3.2.0]hept-2-en-7-ones 2 gave diazepinone derivatives 3 in a base-catalyzed ring-enlargement reaction. With a silyl group on C3, the rearrangement may be initiated by solvolytic cleavage of the Si —C bond with methanol.90... 

A new class of thiazole-fused diazepinones 79 was prepared by treatment of 2-arylamino-4-coumarinyl-5-formyl thiazoles 78 with hydrazine hydrate in refluxing ethanol to yield the rearranged products via ring-opening by attack of the intermediate hydrazone on the lactone of the coumarin <07SC99>. 

Novel non-nucleoside inhibitors of HIV-1 reverse transcriptase, dipyrido[2,3-/)]diazepinones, were prepared by J.R. Proudfoot and co-workers.These compounds are isomeric to the potent inhibitor nevirapine and available via the Smiles rearrangement of substrates that are intermediates used for the synthesis of nevarpine analogs. The deprotonated amide functionality in the rearrangement products displaces the chlorine at the 2-position to give the desired heterocycles in moderate to good yield. 

The formation of pyridine IV-imines by an add-catalyzed rearrangement of some diazepinones and related compounds has been extensively investigated by Moore and co-workers (Eq. 9).115 The formation of pyridine N-imines from l/f-l,2-diazepines is also known (Eq. 10).68 69,116,117 Diels-Alder reactions of pyrazoles with dimethyl acetylenedicarboxylate, in the presence of BF3, have been reported to give IV-aminopyridinium salts (Eq. II).118 l,4-Dihydropyrido[l,2-a]-as-triazinium salts and their pyrimido derivatives undergo ring contraction in boiling aqueous acid, yielding 1-aminoimidazo[l,2-a]pyridinium and pyrimidinium salts, respectively (Eq. 

A-Aminopyridinium salts (14), and their derivatives substituted at the exocyclic amino group, can also be prepared by rearrangement reactions. Thus, the diazepinone 22 and diazepinium betaine 23 are converted into the A-amino salts (26) by concentrated acids.44-47 This rearrangement... 

Sequential base-catalyzed ring closure of diazopropionylpyrazolone (162) and thermal rearrangement of the diazabicycloheptanone (163) gave diazepinone (164) and its 1,5-dihydro isomer (Scheme 24) <85JOC2141>. 

Dihydro-1,2-diazabicyclo [3.2.0] -3-hepten-6-ones MI-312 and XII-313 and diazepinones XII-314 are readily interconvertible ring systemsand all three can give l-amino-3-pyridinol salts (see Section IV.3., p. 839) or 3-pyridinols. When heated in methanol, the 2-acetyl- or 2-benzoyl-derivative of MI-313 rearranges to several products including 6-acetamido- or 6-benzamido-3-hydroxy-4-methjd-5-phenylpyridine (XII-317) in 17% and 68% yield, respectively, presumably through intermediates such as XII-315 and... 

Tetrahydro[l,2]diazepinones have been formed through base-promoted rearrangement of a,/ -epoxy-Af-aziridinylimines (Scheme 184) ... 

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