THIOUREA
Cas No: 62-56-6
Metatags: Thiocarbamide; Isothiourea; 2-Thioure; Tiyoüre; Tiyo Üre; THIOUREA; Thiocarbamide; 2-Thiourea; Sulfourea; Pseudothiourea; Sulourea Urea; Thio-Isothiourea; Thiocarbonic acid diamide; 2-Thiopseudourea; Thiuronium; 2-thio-Pseudourea; 2-thio-beta-Thiopseudourea; Carbamimidothioic acid; tiyo üre; tio üre; tioüre
Thiourea is an organosulfur compound with the formula SC(NH2)2 . It is structurally similar to urea, except that the oxygen atom is replaced by a sulfur atom, but the properties of urea and thiourea differ significantly. Thiourea is a reagent in organic synthesis. “Thioureas” refers to a broad class of compounds with the general structure (R1R2N)(R3R4N)C=S. Thioureas are related to thioamides, e.g. RC(S)NR2, where R is methyl, ethyl, etc.
Thiourea is a planar molecule. The C=S bond distance is 1.60±0.1 Å for thiourea (as well as many of its derivatives). The material has the unusual property of changing to ammonium thiocyanate upon heating above 130 °C. Upon cooling, the ammonium salt converts back to thiourea.
Thiourea occurs in two tautomeric forms. In aqueous solutions the thione form predominates. The thiol form, which is also known as an isothiourea, can be encountered in substituted compounds such as isothiouronium salts.
Thiourea, also called thiocarbamide, an organic compound that resembles urea but contains sulfur instead of oxygen; i.e., the molecular formula is CS(NH2)2, while that of urea is CO(NH2)2. Like urea, it can be prepared by causing a compound with the same chemical composition to undergo rearrangement, as by heating ammonium thiocyanate (NH4SCN). A method of preparation more commonly used consists of the addition of hydrogen sulfide to cyanamide. Thiourea exhibits many of the chemical properties of urea, but it has little commercial application. The small quantity of thiourea consumed is utilized primarily in photography as a fixing agent, in the manufacture of a thermosetting resin, as an insecticide, as a textile-treating agent, and as starting material for certain dyes and drugs. Thiourea forms as colourless crystals melting at 182° C (360° F). It is toxic, although the fatal dosage is not well established.