Synthesis, Spectral Characterization, and Crystal Structure of Two Polymorphs of o,o’-Dichloro Dibenzyl Disulfide

Abstract

2-Chlorophenyl methanethiol undergoes air oxidation catalyzed by different selenides andyields the corresponding disulfide 1 in two polymorphic forms, 1a and 1b. In the molecular structures of the two new polymorphs of o,o -dichloro dibenzyl disulfide, the dihedral angles between the dibenzyl groups are 82.0(1) • , (1a), and 73.7(4) • , (1b), respectively [(1a): P-1, a = 8.424(2) Å, b = 8.838(2) Å, c = 10.5823(19) Å, α = 90.122(18) • , β = 112.19(2) • , γ = 95.19(2) • , V = 725.9(3) Å 3 ; (1b): P2 1 /n, a = 10.5888(10) Å, b = 9.1590(6) Å, c = 15.2489(14) Å, β = 103.072(9) • , V = 1440.6(2) Å 3 ]. MOPAC computational studies yield dihedral angles of 89.6(5) • and 71.9(9) • . Crystal packing is stabilized by weak π -ring (C H· · ·Cg) intermolecular interactions in both 1a and 1b and by additional weak Cg · · · Cg intermolecular interactions in 1b, which influence the bond distances, bond angles, and torsion angles of the dibenzyl groups in each polymorph. Additional characterization of each polymorph has been carried out by TEM, IR, 1 H and 13 C NMR spectroscopy, microanalysis, and by FAB mass spectrometry. TEM studies of a sample of 1a show that it contains cigar-shaped crystallites.