Methyl 2-benzoylbenzoate is an o-acyl-aromatic ester combining a benzophenone chromophore with a methyl ester group. The conjugated keto-ester system gives strong UV-A absorption (λmax ≈ 320 nm, log ε 3.9), excellent thermal stability and low volatility. It is sparingly soluble in water (≈ 0.14 g L⁻¹ at 25 °C), freely soluble in ethanol, acetone, toluene and most acrylic monomers, and can be recrystallised from methanol. Commercial product is supplied at ≥ 99 % purity and remains stable for ≥ 2 years when stored at room temperature in tightly closed containers away from light.
Key Physicochemical Data:
Melting point: 48–53 °C
Boiling point: 352 °C / 760 mmHg
Density: 1.17 g cm⁻³ (20 °C)
Flash point: > 110 °C (closed cup)
Log P (octanol/water): 2.8 (25 °C)
Vapour pressure: < 0.001 Pa at 20 °C
Typical Uses:
High-performance Type II photoinitiator for UV-curable clear coatings, inks, adhesives and 3-D printing resins; especially suited for thick-section or pigmented systems .
UV-A absorber and preservative in food-contact and cosmetic packaging materials .
Key intermediate for the synthesis of benzophenone-2-carboxylic acid derivatives, pharmaceutical APIs and OLED materials .
Quality Specification (Commercial Grade):
Purity (HPLC): ≥ 99 %
Water content (KF): ≤ 0.3 %
Individual impurity (GC): ≤ 0.5 %
Total impurities (GC): ≤ 1.0 %
Heavy metals: ≤ 20 ppm
Hazard Statement:
Harmful to aquatic life with long-lasting effects (H411); causes skin and eye irritation (H315 + H319). Avoid release to the environment; use gloves, goggles and adequate ventilation. Store in a cool, dry place away from oxidants and strong bases. SDS available on request.
