Synthesis and Solid-state Reaction of 1-[3′-(Benzotriazol-2″-yl)-4′ -hydroxybenzoyl]-3-methyl-5-pyrazolones

✍ Scribed by Xiao-Chun Han; Xue-Yu Xu; Xiao-Lu Li; Yong-Mei Wang; Teruo Matsuura; Ji-Ben Meng

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 377 KB
• Volume: 19
• Category: Article
• ISSN: 0256-7660
• DOI: 10.1002/cjoc.20010190415

✦ Synopsis

Abstract

A new kind of UV stabilizers, 1‐(3′‐(benzotriazol‐2″‐yl)‐4′‐hydroxy‐benzoyl)‐3‐methyl‐5‐pyrazolones (1a‐d), was synthesized with the aim to bind them chemically to certain polymers. The reaction of 1d with substituted benzaldehydes 4 in the molten state at 150°C and in the solid state at room temperature produced the condensation products l‐(3′‐(5″‐chlorobenzotriazol‐2″‐yl)‐4′‐hydroxyl‐5′‐chlorobenzoyl)‐3‐methyl‐4‐arylmethylene‐5‐pyrazolones (2) and 4,4′‐arylmethylene‐bis [1‐(3′‐(5″‐chloro‐benzotriazol‐2″‐yl)‐4′‐hydroxy‐5′‐chloro‐benzoyl)‐3‐methyl‐5‐pyrazolone] s (3), respectively, as the major product. On the other hand, the reaction of 1d with 4 at 50°C in chloroform solution proceeded non‐selectively to give a mixture of 2 and 3.