2mercaptopyridineNoxide

2-Mercaptopyridine, also called 2-pyridinethiol, is an organosulfur heteroaromatic compound with the formula C5H5NS. It consists of a pyridine ring bearing a thiol (-SH) substituent at the 2-position. The molecule is commonly encountered as a solid and is notable for its thiol functionality, which can undergo oxidation to form disulfides and for its potential to act as a multidentate ligand in coordination chemistry.

In coordination chemistry, 2-mercaptopyridine behaves as a bidentate ligand, coordinating to metal centers through the thiolate sulfur and the pyridine nitrogen to form chelate complexes. Such ligands stabilize a range of transition-metal complexes and have been studied for catalysis and materials applications. The thiol group also allows the formation of metal-thiolates, including disulfide formation upon oxidation.

Synthesis of 2-mercaptopyridine is typically achieved by thiolation of 2-halo-pyridines. A common route involves nucleophilic substitution of 2-bromopyridine or 2-chloropyridine with thiolate sources such as sodium hydrosulfide or thiourea under basic conditions, followed by purification. Alternative methods include reduction of the corresponding 2-pyridyl disulfide or the use of thioamide precursors.

Industrial and laboratory uses include serving as a modular building block for ligand design, construction of metal complexes, and as an intermediate in organic synthesis. It is important to handle 2-mercaptopyridine with care due to the odor and potential irritant and toxic properties of thiols. Safety precautions include working in a fume hood, wearing appropriate protective equipment, and avoiding inhalation or skin contact.