Crystal structure of 1,2-bis(6-bromo-3,4-dihydro-2H-benz[e][1,3] oxazin-3-yl) ethane: a brominecontaining bis-benzoxazine

The title benzoxazine molecule, C18H18Br2N2O2, was prepared by a Mannichtype reaction of 4-bromophenol with ethane-1,2-diamine and formaldehyde. The title compound crystallizes in the monoclinic space group C-2/c with a centre of inversion located at the mid-point of the C-C bond of the central CH2CH2 spacer. The oxazinic ring adopts a half-chair conformation. The structure is compared to those of other functionalized benzoxazines synthesized in our laboratory. In the crystal, weak C-H center dot center dot center dot Br and C-H center dot center dot center dot O hydrogen bonds stack the molecules along the b-axis direction.