In (2SR,4RS)-2-exo-vinyl-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(12)H(13)NO, (I), the molecules are linked by two independent C-H...pi(arene) hydrogen bonds to form sheets, such that all of the molecules in a given sheet are of the same configuration. The molecules of (2SR,4RS)-7-chloro-2-exo-(2-methylprop-1-enyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(14)H(16)ClNO, (II), are linked by a C-H...O hydrogen bond into C(4) chains, where all the molecules in a given chain are of the same configuration, whereas the molecules of (2SR,4RS)-8-chloro-9-methyl-2-exo-(2-methylprop-1-enyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(15)H(18)ClNO, (III), are linked into centrosymmetric dimers by pairs of symmetry-related C-H...pi(arene) hydrogen bonds. (2RS,4RS)-8-Chloro-9-methyl-2-endo-(2-methylprop-1-enyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(15)H(18)ClNO, (IV), is a diastereoisomer of (III) and, as for (II), a single C-H...O hydrogen bond links the molecules into C(4) chains, each containing molecules of a single configuration. The structure of (2SR,4RS)-8-chloro-9-methyl-2-exo-(prop-1-en-2-yl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(14)H(16)ClNO, (V), contains a C-H...O hydrogen bond which links pairs of molecules into centrosymmetric R(2)(2)(6) dimers. (2SR,4RS)-7,9-Dichloro-2-exo-(prop-1-en-2-yl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(13)H(13)Cl(2)NO, (VI), is an inversion twin containing both the (2S,4R) and (2R,4S) enantiomers in the space group P2(1), and a C-H...O hydrogen bond links molecules of a given configuration into simple C(3) chains.