关键词: 可见光催化, 对甲氧基苯甲醛, 对甲氧基苯甲酸甲酯, 药物中间体, 克级合成

Abstract:

Methyl p-methoxybenzoate, a critical intermediate in fragrance and anticancer drug synthesis, has attracted significant attention for its efficient and green preparation. To address the limitations of conventional multi-step methods, such as the use of corrosive strong acids and the generation of multiple byproducts, this study developed a novel visible-light-driven one-step synthesis protocol. Utilizing an acridinium salt as the photocatalyst and methanol as both the solvent and nucleophilic reagent, the target product was efficiently synthesized via a photoinduced radical relay mechanism under aerobic conditions. Experimental results demonstrated a 90% yield after 3h of reaction at room temperature with the yield remaining above 78% in gram-scale amplification experiments. Comparative analysis highlighted the superior advantages of this approach: a one-step esterification process that eliminated traditional separation procedures; a mild reaction system free from strong acids and noble metals, ensuring excellent equipment compatibility; significantly enhanced atom economy and aligning with environmentally friendly catalytic principles. This strategy was extendable to the synthesis of various substituted aromatic esters, offering an efficient and scalable green methodology for the production of fragrance and anticancer drug intermediates.

Key words: visible-light photocatalysis, p-methoxybenzaldehyde, methyl p-methoxybenzoate, pharmaceutical intermediates, gram-scale synthesis