2-Mercaptopyrimidine

Updated: 2026-07-15

Overview

2-Mercaptopyrimidine is an organosulfur compound featuring a pyrimidine ring substituted with a thiol group at the 2-position. This heterocyclic building block plays significant roles in medicinal chemistry and material science due to its dual functionality as both a nucleophile (via sulfur) and hydrogen bond acceptor (via nitrogen atoms). The compound was first synthesized in the early 20th century during studies of pyrimidine derivatives. Industrial production typically involves the reaction of 2-chloropyrimidine with thiourea or similar sulfur-transfer reagents under controlled conditions.

Physical and Chemical Properties

As a crystalline solid, 2-mercaptopyrimidine exhibits moderate stability under normal conditions but may decompose when exposed to strong oxidizers or prolonged heat. The thiol group confers weak acidity (pKa ~7.5), allowing formation of stable metal complexes with transition metals like copper and zinc. Characteristic IR absorption bands appear at 2550 cm-1 (S-H stretch) and 1570 cm-1 (C=N stretch). The compound shows tautomerism between thiol and thione forms in solution, with the thione form typically predominating in polar solvents. UV-Vis spectroscopy reveals maximum absorbance around 270-280 nm.

Main Applications

In pharmaceuticals, 2-mercaptopyrimidine serves as a precursor for antithyroid drugs (e.g., methimazole analogs) and antiviral agents. The sulfur atom participates in crucial binding interactions with biological targets, particularly in enzyme inhibition applications. Industrial uses include formulation of copper corrosion inhibitors for cooling systems, where it forms protective films on metal surfaces. Specialty chemical manufacturers employ it as a ligand in catalytic systems and as a building block for more complex heterocycles like thienopyrimidines.

Safety and Storage

Proper handling requires nitrile gloves, safety goggles, and fume control due to potential respiratory and dermal irritation. The compound is not considered highly toxic (LD50 oral rat >500 mg/kg) but may cause sensitization upon repeated exposure. Storage recommendations include amber glass containers or polyethylene-lined drums with desiccants to prevent moisture absorption. Shelf life typically exceeds 24 months when stored below 30°C with inert gas blanket for premium grades. Incompatibilities include strong oxidizers, acids, and bases.

B2B Procurement Guide

Technical specifications should specify minimum purity (typically 98-99.5%), heavy metal content (<10 ppm), and residual solvent levels. Pharmaceutical-grade material requires additional documentation including Certificate of Analysis (CoA), DMF references, and GMP compliance statements. Bulk shipments commonly use 25kg fiber drums with polyethylene liners, while smaller quantities may be packaged in double-sealed foil bags. Leading manufacturers are concentrated in China and India, with some European specialty chemical producers offering high-purity variants at premium prices.