The condensation of p-nitrothiophenol with formaldehyde and trichloroacetaldehyde. Structure of 2,2-bis(4′-nitro-1′-mercaptophenyl)-1,1,1-trichloroethane

The condensation ofp-nitrothiophenol with formaldehyde and with trichloroacetaldehyde is described. 2,2-Bis(4′-nitro-1′-mercaptophenyl)-1,1,1-trichloroethane is monoclinic,P21/c,a=7.717(2),b=34.666(5),c=7.258(1) (Å),β=116.32 (1) (deg.),V=1740.35 (Å3),Z=4. The structure was solved by direct methods, from data collected at room temperature on an Enraf-Nonius CAD4 diffractometer, and refined by full-matrix least squares to a finalR value of 0.052 using 1722 reflections. The torsion angles S-C-S-CAr are 159.7(3) and −90.5(4) (deg). The mean planes of the aromatic rings are at 46.8(2) (deg.) to one another. Evidence of intramolecular crowding is given by the inequality of several pairs of angles which would otherwise have been expected to be equal. The bond lengths are normal.