The vicinal dibromides of α,β-unsaturated carboxylic acid derivatives were debrominated with Sm/TiCl4 system to afford the corresponding cinnamic acid derivatives in good yields under mild conditions.
N Hydroxysuccinimide was synthesized from succinic anhydride and hydroxylamine in yield 58%~61% with purity ≥97%. The method has advantages of simplicity and high yield and purity.