Crystal structures of two thiazolidinone derivatives bearing a trichloromethyl substituent at the 2-position

The title compounds 2-trichloromethyl-3-phenyl-1,3-thiazolidin-4-one (C 10 H 8 Cl 3 NOS), 1 and 3-(4-chlorophenyl)-2-trichloromethyl-1,3-thiazolidin-4-one (C 10 H 7 Cl 4 NOS) 2, are structurally related with one atom substitution difference in the para position of the benzene ring. In both structures, the thiazolidinone ring adopts an envelope conformation with the S atom as the flap. The dihedral angles between the rings [48.72 (11) in 1 and 48.42 (9)° in 2] are very similar and the molecules are almost superimposable. In both crystal structures, C - H⋯O 'head-to-tail' interactions between the chiral carbon atoms and the thiazolidinone oxygen atoms result in infinite monochiral chains along the direction of the shortest unit-cell parameter, namely a in 1 and b in 2. C - H⋯π interactions between the thiazolidinone carbon atom at the 4-position and the phenyl ring of the neighboring enantiomer also help to stabilize the packing in each case, although the crystals are not isostructural.