3H-2-Benzazepine

H-2-Benzazepine, 1-aryltetrahydro-synthesis, 7, 532-533 3H-2-Benzazepine, 4,5-dihydro-quatemization, 7, 511 synthesis, 7, 532... 

H-2-Benzazepine, (halophenethyl)-ring expansion, 7, 528 3H-2-Benzazepine, 1-phenyl-synthesis, 7, 540... 

There are only a few reports concerning the peracid oxidation of azepines. 30% Hydrogen peroxide oxidizes TV-alkyl-6,7-dihydro-5iT-dibenz[c,e]azepines to their TV-oxides (75ZN(B)926), whereas MCPBA has been used to prepare the 3H-2-benzazepine TV-oxide (88) (74JOC2031). TV-Oxidation of 2,3,4,5-tetrahydro-lH-l-benzazepine with MCPBA is accompanied by dehydrogenation to the 4,5-dihydro TV-oxide (89) (79JOC4213). 

Sodium borohydride reduction of the azomethine bond has been noted for 3H-2-benzazepines (75JA4682,76HCA623) and for ll//-dibenz[6,e]azepines (65CCC445). 

DMAD does not form cycloadducts with l-phenyl-3H-2-benzazepine nor with the anion of l-tosyl-2,3,4,5-tetrahydro-lH-l-benzazepin-5-one. Instead, the former yields 5H-2-benzazepine (144) via a concerted ene reaction (75JA4682), whereas the latter affords the benzazonine (145) by ring expansion of the initially formed C-4—C-5 [2+2] adduct (80JCS(P1)1251). 

Aza-l, 3-l i5(triphenylphosphoranyhdene)propane (24), a novel syn-thon, was prepared in situ by reaction of the iminophosphorane (21) with methylenetriphenylphosphorane (22) followed by treatment of the intermediate (23) with n-butylhthium. Reaction of yhde (24) with dialdehydes (e.g., 25) or diketones (e.g., 26) gave good yields of 3H-2-benzazepine (27) and 2,3-disubstituted pyrroles (28a—c), respectively (Scheme 8) (1994JOC4551). 

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