Enanti-opure ()-butan-2-yl -(4--phen-yl)thio-carbamates, = NO, OCH, F, and Cl.

The structures of ()-butan-2-yl -(4-nitro-phen-yl)thio-carbamate, CHNOS, (I), ()-butan-2-yl -(4-meth-oxy-phen-yl)thio-carbamate, CHNOS, (II), ()-butan-2-yl -(4-fluoro-phen-yl)thio-carbamate, CHFNOS, (III), and ()-butan-2-yl -(4-chloro-phen-yl)thio-carbamate, CHClNOS, (IV), all at 100 K, have monoclinic (2) symmetry with two independent mol-ecules in the asymmetric unit. The Flack absolute structure parameters in all cases confirm the absence of inversion symmetry. The structures display N-H⋯S hydrogen bonds, resulting in (8) hydrogen-bonded ring synthons connecting the two independent mol-ecules. Despite the ring synthon, the packing follows two distinct patterns, with (I) and (IV) 'pancaking' along the axis direction, while the other two 'sandwich' in layers perpendicular to the axis. Crystal morphologies were determined theoretically the BFDH (Bravais, Friedel, Donnay-Harker) model and agree qualitatively with the experimentally indexed results. One of the butyl substituent of (II) exhibits structural disorder.