Tetraphenyl-1,3-oxazepines

Irradiation of the unsymmetrically substituted 2,3,4,6-tetraphenylpyridine 1-oxide (5) under these conditions gives 2,4,6,7-tetraphenyl-l, 3-oxazepine (7) in 30 % yield, together with 2,4,5,6-tetraphenylpyridin-3-ol (10) in 37% yield and 2,3,4,6-tetraphenylpyridine (30%).11 It has been suggested that the reaction proceeds by way of the oxaziridines 6 (which yields 7) and 8 (which yields the isomeric oxazepine 9) the latter rearranges to the pyridinol 10. 

Seven-membered-ring compounds which have been studied include several azepine and benzazepine derivatives. In (3-acetyl-177-azepine)tricarbonyl-iron(0), the azepine ring is bonded to the iron atom via the butadiene fragment C(4)—C(7). The conformation of the azepine ring is described by the two planar halves formed by atoms C(4)—C(7) and by N(l) and C(2)— C(4), the dihedral angle between the planes being 141°. The oxazepine rings of both 2,4,5,7-tetraphenyl-6-(p-bromophenyl)-l,3-oxazepine (48) ... 

C3 2Hft 9NO3, 2,4-Di-t-butyl-6-(3,5-di-t-butyl-2-hydroxyphenyl)-6-morpholinocyclohexa-2,4-dienone, 44B, 351 C3 5H2 BrNO, 2,4,5,7-Tetraphenyl-6-(4-bromophenyl)-1,3-oxazepine,... 

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