Different hydrogen-bonded structures in three 2-thienyl-substituted tetrahydro-1,4-epoxy-1-benzazepines.

The molecules of (2RS,4SR)-2-exo-(5-bromo-2-thienyl)-7-chloro-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(14)H(11)BrClNOS, (I), are linked into cyclic centrosymmetric dimers by C-H...pi(thienyl) hydrogen bonds. Each such dimer makes rather short Br...Br contacts with two other dimers. In (2RS,4SR)-2-exo-(5-methyl-2-thienyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(15)H(15)NOS, (II), a combination of C-H...O and C-H...pi(thienyl) hydrogen bonds links the molecules into chains of rings. A more complex chain of rings is formed in (2RS,4SR)-7-chloro-2-exo-(5-methyl-2-thienyl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, C(15)H(14)ClNOS, (III), built from a combination of two independent C-H...O hydrogen bonds, one C-H...pi(arene) hydrogen bond and one C-H...pi(thienyl) hydrogen bond.