13453-33-3

white crystal(s) [STR93]

According to Meyer, TlCl ? 4H2O is prepared by passing Cl2 through a nearly boiling suspension of TlCl in a limited amount of water. After intermediate Tl(I)-T1(III) chloro compounds have dissolved, the solution is evaporated to a thin syrup with continuous addition of Cl2 . The water bath temperature should be 60-70°C. The syrup immediately solidifies to a slurry of fine, white needles of TlCl ? 4 H2O on cooling in an ice bath, larger crystals form on slower cooling. The crystals are rapidly filtered and dried 24 hours over H2SO4 andKOH(virtually no efflorescence). Cushman claims that TlC13 . 4 H2O crystals can only be dried between filter papers if loss of water is to be avoided. Hecht states that he found no definite tetrahydrates.
TlCl + Cl2 + 4H2O = TlCl3 ? 4H2O