4-(Methylthio)benzaldehyde is an aromatic aldehyde bearing a lipophilic methylthio group at the para-position. The compound is air-stable, readily soluble in common organic solvents (dichloromethane, ethyl acetate, methanol, ethanol) and only sparingly soluble in water.
Key physical data:
Density: 1.15 g cm⁻³ (25 °C)
Refractive index: n²⁰/D 1.62
Boiling point: 275 °C / 760 mmHg
Flash point: >110 °C
Typical uses:
Key precursor for the veterinary antibiotic florfenicol and for d-ethyl p-methylsulfonylphenylserinate intermediates; the aldehyde is first oxidised to the sulfone, then submitted to further C–C bond formation .
Building block for sulfur-containing terpyridine ligands and for pyrrole derivatives that show analgesic/anti-inflammatory activity .
Starting material for UV-absorbers, liquid-crystalline materials and fluorescent probes.
Quality specification (commercial grade):
Purity (GC): ≥97 %
Water content (KF): ≤0.3 %
Free acid (as 4-methylthiobenzoic acid): ≤0.5 %
Residue on ignition: ≤0.1 %
Hazard statement:
Harmful if swallowed (H302). Causes skin and eye irritation. Avoid ingestion and inhalation; use gloves, goggles and adequate ventilation. SDS available on request .
