Secondary interactions in the crystal structures of three 1,2,4,5-tetrakis(bromomethyl)-3,6-bis(2-alkoxy)benzenes

Crystal structures of three 1,2,4,5-tetrakis(bromomethyl)-3,6-bis(2-alkoxy)benzenes 1–3 with different length and branching of alkyl chains are analyzed. X-ray structure determinations showed relatively undistorted molecular structures. Crystal packing is defined by networks of C–H⋯Br weak hydrogen bonds, short Br⋯Br contacts, and one particularly short C–H⋯π contact, although the major share of the cohesive energy of the structures is due to dispersion interactions. Z′ = 2 for 1 can be explained in terms of these interactions, which were shown to be stronger between the asymmetric pairs of molecules with the help of OPiX calculations. Surprisingly, the role of the oxygen atoms in intermolecular crystal packing is relatively small.