University Chemistry ›› 2024, Vol. 39 ›› Issue (4): 322-328.doi: 10.3866/PKU.DXHX202309095

• Chemistry Laboratory • Previous Articles     Next Articles

Preparation of Trans-Cinnamic Acid via “One-Pot” Protocol of Aldol Condensation-Hydrolysis Reaction: Recommending an Improved Organic Synthesis Experiment

Yukun Chang, Haoqin Huang, Baolei Wang   

  1. State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
  • Received:2023-09-25 Revised:2023-11-29 Published:2024-04-17

Abstract: Cinnamic acid is an important intermediate in organic synthesis and a valuable raw material in the fine chemicals industry, with a wide range of applications across various fields. The preparation of cinnamic acid is a significant component in undergraduate organic chemistry experiments. Traditionally, it is achieved through the classic Perkin reaction, using benzaldehyde and acetic anhydride as starting materials and employing potassium acetate/potassium carbonate as catalysts. This article proposes a novel approach, namely the Aldol condensation-hydrolysis method, for the synthesis of trans-cinnamic acid. In this method, benzaldehyde, ethyl acetate, and potassium tert-butoxide are used as reactants, and the reaction proceeds through a “one-pot” process involving reflux, distillation, alkali hydrolysis, distillation again, and acidification, ultimately yielding pure trans-cinnamic acid. This method offers numerous advantages, including the use of inexpensive raw materials and reagents, low quantities required, simple equipment setup, low energy consumption, easy operation, high yield, short reaction time, and minimal environmental pollution. Therefore, it is highly recommended for undergraduate experimental teaching. Furthermore, this method not only helps students acquire a comprehensive understanding of fundamental theoretical knowledge and experimental skills but also encourages them to think innovatively in terms of convenient and efficient synthesis of organic compounds. Additionally, it fosters awareness of energy conservation and environmental protection, contributing to the development of well-rounded individuals.

Key words: Trans-Cinnamic acid, Benzaldehyde, Ethyl acetate, Potassium tert-butoxide, “One-pot” synthesis