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I-. 2-. and 3-Benzazepines

Acyl-3.4-benzo-2-azabicyclo[3.2.0]hepta-3,6-dienes 1, on heating at 250-280 C for a short time without solvent, rearrange to the 1-acyl-1-benzazepines 2 (Method A).23-38 In some cases, rearrangement is accompanied by minor amounts of Ar-aeyl-l-naphthylamine and, at higher temperatures, the acylnaphthylatnine can become the major product (see Section 3.2.2.6.). In the presence of silver(I) tetrafluoroborate (Method B) rearrangement takes place at lower temperatures but the yields of benzazepine are inferior as the silver(I) ion also catalyzes the reverse reaction (see Section 3.2.2.1.). [Pg.238]

Benzoyl-l-methyl-3,4-benzo-2-azabicyclo[3.2.0]hepta-3.6-diene (3) at 250"C yields exclusively l-benzoyl-2-mcthyl-l//-l-benzazepine (4).23 In contrast, silvcr(I) ion catalyzed ring expansion of 3 yields a mixture of the rearranged bicycle 5 (43 %), starting material (43 %), and the isomeric 1 H-l-benzazepines 4 (8%) and 6 (4%).23... [Pg.238]

In contrast, the photolysis of 2,7-diazidonaphthalene (18) furnishes a mixture of 8-azido-2-methoxv-1//-2-benzazepine(l9), 3,8-dimethoxy-l,6-dihydroazepino[3,4-c]azepine(20) and, unexpectedly, the 1 /i-2-benzazepin-8-amine 21 as the major product (40-50%). [Pg.256]

Benzazepines 1 are oxidized to their 7V-oxides 2 by 3-chloroperoxybenzoic acid (1 equivalent) at room temperature.78 1 78 However, at higher temperatures, and with an excess of oxidant,178 or with a stronger peracid.78 N-oxide formation is accompanied by epoxidation at C4-C5 (see Section 3.2.2.2.I.). [Pg.257]

The thermally induced electrocyclic ring opening of 2-alkyl- and 2-acyl-3.4-benzo-2-azabicyclo-[3.2.0]hepta-3,6-dienes 2 to l//-l-benzazepines 1 (see Section 3.2.1.4.1.1.) are photorever-sible.23,37 38 Also, l-acyl-1//-benzazepines 1 (R = acyl), in refluxing xylene in the presence of silver(I) tetrafluoroborate, are in thermal equilibrium with their valence isomers the 2-acyl-3,4-benzo-2-azabicyclo[3.2.Oj nepia-3,6-uienes 2 (R = acyl).23-38... [Pg.280]

Recently, a new reactivity index has been proposed (80H(14)1717> which predicts accurately the site selectivity of photocyclization of substituted cycloheptatrienes to their bicyclic valence tautomers. Unfortunately, application of the method to substituted lH-azepines is far less successful. For example, for 2-methyl-l-methoxycarbonyl-lH-azepine (37 R = 2-Me) AGrs values for C-2—C-5 and C-4—C-7 cyclization are calculated as 0.093 and 0.040 kJ mol-1, respectively, i.e. predicting the 1-methyl isomer (39) as the major product. Experimentally, however, the reverse is true, the yields being 93.5% for 3-methyl (38 R = Me) and 6.5% for 1-methyl (39 R = Me). The corresponding photoinduced valence isomerizations of 1-benzazepines to 3,4-benz-2-azabicyclo[3.2.0]hepta-3,6-dienes (38a) have been recorded (80JOC462). These isomerizations have also been achieved thermally in the presence of silver ion (80TL3403). [Pg.504]

Direct electrophilic substitution of benz- and dibenz-azepines remains relatively unexplored. Most substituted benzazepines have been prepared from benzene precursors bearing the desired substituents (74AHC(17)45). The bulk of the reported electrophilic substitutions have been carried out on 5//-dibenz[6,/]azepine (74CRV101), MO calculations on which predict that substitution should occur at the 2- and 4-positions, i.e. para and ortho to the azepine ring nitrogen. These predictions are borne out by Friedel-Crafts alkylation and acylation studies, although it is apparent that a second alkyl group enters at the 8- rather than at the 4-position. Formylation under Vilsmeier conditions yields the 2-aldehyde. As noted earlier (Section 5.16.3.4), however, the 10,11-dihydro system exhibits different behavior and acylates at the benzylic 10,11-positions. Nitration with mixed acids of the... [Pg.527]

Remy, D.C., Britcher, S.F., King, S.W., Anderson, P.S., Hunt, C.A., et al. (1983) Synthesis and receptor binding studies relevant to the neuroleptic activities of some l-methyl-4-pipeiidylcnc-9-substi-tuted-pyrrolo[2,l-i>][3]benzazepine derivatives. J. Med Chem. 26 974-980. [Pg.325]

Excess ethereal diazomethane added at 0° to a methanolic soln. of the startg. m., and the product isolated the next day 5-(3,4-dimethoxybenzoyl)-2,3-dihydro-7,8-dimethoxy-3-methyl-lH-3-benzazepine. Y 82%. T. Kametani et al., Soc. Perkin I 1974, 2509. [Pg.211]

As shown in Scheme 5.23, 1,2,3,4-tetrahydroquinoline derivatives were synthesized using 3-(2-aminophenyl)propanols as starhng materials and catalyzed by the I/K2CO3 system. This catalytic system was also applicable to the synthesis of 2,3,4,5-tetrahydro-l-benzazepine from 4-(2-aminophenyl)butanol. [Pg.126]

Derivatives of the single step product are used in the preparation of 4-carboxy-1,2,3-triazole intermediates, (I), the latter which is used to prepare benzazepine and benzoth-iazepine derivatives (2). Prior to the current invention, the key intermediate was prepared in a two step process illustrated in Eq. 1 ... [Pg.669]


See other pages where I-. 2-. and 3-Benzazepines is mentioned: [Pg.342]    [Pg.293]    [Pg.345]    [Pg.342]    [Pg.293]    [Pg.345]    [Pg.492]    [Pg.530]    [Pg.492]    [Pg.530]    [Pg.492]    [Pg.530]    [Pg.45]    [Pg.327]    [Pg.158]    [Pg.224]    [Pg.233]    [Pg.241]    [Pg.580]    [Pg.984]    [Pg.463]    [Pg.534]    [Pg.2130]    [Pg.38]    [Pg.135]    [Pg.236]    [Pg.55]    [Pg.528]    [Pg.540]    [Pg.67]    [Pg.121]    [Pg.541]    [Pg.72]   
See also in sourсe #XX -- [ Pg.17 , Pg.45 ]

See also in sourсe #XX -- [ Pg.17 , Pg.45 ]




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