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1,2,4-Triazepines

3-Benzodiazepines (24b) exist as such and not as the antiaromatic 3//-tautomers 24a [73JCS(P1)2543 83H2173]. A different tautomer (5H) was observed for Tofizopam (25) using and NMR (74CB3894) and X-ray structure analysis [86JST(147)143]. Tire same behavior is observed [Pg.7]

Tire only known example of 1,2,3-triazepine (32) behaves as a reactive cyclic triazene with a high degree of masked diazonium character [74JCS(P1)1248]. 277-1,2,4-Triazepine (33a) has been obtained from the 577-tautomer (33b) by a 1,5-hydrogen shift (74CC45,74TL2303), this being one of these rare cases that an antiaromatic tautomer 33a is more stable than the nonaromatic one 33b. But it must be noted that these 277-1,2,4-tri- [Pg.8]


The synthesis of 9H-benzo[2,l-e]thiazolo-[2,3-c]-as-triazine (401) was achieved by oxydative cyclization of 2-imino-3-(o-aminophenyl)-4-phenyl-4-thiazoline (718, 719). This latter reacts also with paraformaldehyde in hot toluene yielding 3-phenyl-9H.10H-benzo[l,2-/]thiazolo-[2,3-d][l,3,5]triazepine (402) (720). This heterocyclic sytem is also formed when carboxylic acids replace paraformaldehyde (Scheme 230) (721). [Pg.129]

Photolysis of pyridazine IV-ethoxycarbonylimide results in the formation of the pyrrole derivative (56). The rearrangement is postulated to proceed via a diaziridine, followed by ring expansion to the corresponding 1,2,3-triazepine derivative and rearrangement to a triazabicycloheptadiene, from which finally a molecule of nitrogen is eliminated (Scheme 19) (80CPB2676). [Pg.13]

Triazepine, 5-benzyl-3,7-diaryl-4,6-dihydro-imidazole synthesis from, 5, 497... [Pg.897]

Some triazepinones in which one of the nitrogen atoms belongs to a fused azole moiety have been reported. For instance, compound 63 was prepared (74JHC751) and its X-ray structure determined (75CSC317). Similarly, and NMR spectra and X-ray structural determination of 64 revealed that this compound exists as a 3//-tautomer with the 1,2,4-triazepine ring in a distorted boat conformation (88T7185). [Pg.15]

Alkaline hydrolysis gives either 3//-l,5-benzodiazepine-2,4-diamine (5) or the benzo-triazepine 6 (see Section 4.2.4.4.2.). depending on the strength of the alkali. With hot water the benzimidazole 7 (see Houben-Weyl, Vol.E8c, p 1315) is produced.254... [Pg.429]

Derivatives or benzo analogs of all four possible 1//-triazepine systems are known. [Pg.452]

Catalytic hydrogenation of 5//-dibenzo[r/,/][l, 2,3]triazepine gives biphenyl-2-amine (2).331... [Pg.453]

Cycloaddition of azirines 5 to 1.2,4,5-tetrazines 6 is followed by loss of nitrogen and ring enlargement to yield 5//-1,2,4-triazepines 7, which tautomerize spontaneously by a [1,51-hydrogen shift to the 2/7-1,2,4-triazepines 8. The triazepinesare accompanied by variable amounts of pyrimidines and pyrazoles.335 - 338... [Pg.455]

Irradiation of a benzene solution of 7-benzyl-2,5-diphenyl-3,4,7-triazanorcara-2,4-diene (15) with a high-pressure mercury lamp (Pyrex filter) results in a photochemical walk rearrangement to give 4-benzyl-3,7-diphenyl-477-l, 2,4-triazepine (16) in 53 % yield, accompanied by A-benzyl-3,6-diphenylpyridazin-4-amine (6%), 1-benzyl-2,3-diphenylpyrrole (1%) and... [Pg.456]

Triphenyl-2//-l,2,4-triazepine reacts with tosyl chloride under standard conditions to afford the 2-tosyl derivative 20.337... [Pg.457]

Benzoyl-3,6,7-triphcnyl-2//-l,2,4-triazepine (35%) is obtained from benzoyl chloride and... [Pg.457]

Thermolysis of 4-benzyl-3,7-diphenyl-4/7-l,2,4-triazepine gives a mixture of the rearranged pyrazole 2, 2.4-diphenylpyrimidine and l-benzyl-4-phenylimidazole.341... [Pg.458]

The Diels-Alder adduct 4 of dimethyl acetylenedicarboxylate and the triazepine 3 undergoes rearrangement and elimination of methancthiol to give the pyrazolo[3,4-/ ]pyridine 5.342... [Pg.458]

An interpretation based on frontier molecular orbital theory of the regiochemistry of Diels Alder and 1,3-dipolar cycloaddition reactions of the triazepine 3 is available.343 2,4,6-Trimethyl-benzonitrile oxide, for example, yields initially the adduct 6.344... [Pg.458]


See other pages where 1,2,4-Triazepines is mentioned: [Pg.102]    [Pg.21]    [Pg.281]    [Pg.897]    [Pg.897]    [Pg.897]    [Pg.897]    [Pg.897]    [Pg.897]    [Pg.897]    [Pg.7]    [Pg.14]    [Pg.243]    [Pg.452]    [Pg.452]    [Pg.452]    [Pg.452]    [Pg.452]    [Pg.452]    [Pg.453]    [Pg.454]    [Pg.454]    [Pg.455]    [Pg.455]    [Pg.455]    [Pg.456]    [Pg.456]    [Pg.457]    [Pg.457]    [Pg.457]   
See also in sourсe #XX -- [ Pg.262 ]

See also in sourсe #XX -- [ Pg.370 ]




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1,2,4-Triazepines, fused

1.2.3- Triazino triazepines

1.2.4- Triazoles 1.2.4- triazepines

1.2.4- Triazolo triazepines

1.2.4.5- Tetrazines 1.2.4- triazepines

2-Aryl-1,2,4-triazepin-3-ones

2//-12,4-Triazepine, structure

2//-l,2,4-Triazepine

5//-1,3,5-Triazepine-2,4-dione

5H-Dibenzo triazepines

Dibenzo triazepines

Imidazo triazepines

Triazepine

Triazepine

Triazepine derivatives

Triazepines, synthesis

Triazepines, synthesis from

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