The title salt, C24H27N2OS+·BF4−, was prepared by an alkylation at the amino N atom attached to the sulfur atom of the corresponding sulfodiimide. The configuration around the sulfur atom is a slightly distorted tetrahedral geometry with two S—N bonds and two S—C bonds. The lengths of the S—N(diethylamine) and S=N(m-methylbenzoylimine) bonds are 1.619 (2) and 1.551 (2) Å, respectively. The two N—S—N—C(ethyl) and the N—S—N—C(m-methylbenzoylimine) torsion angles are −85.43 (3), 58.94 (17) and 62.03 (16)°, respectively. The dihedral angle between the two phenyl rings is 84.03 (14)°. In the crystal, C—H...F hydrogen bonds link the cation and anion, forming a three-dimensional network.
