Solvent-free preparation method for substituted cyanoacetate compound

The invention discloses a solvent-free preparation method for a substituted cyanoacetate compound. The method is characterized by comprising the following steps: subjecting an aldehyde compound (I) represented by a formula shown in the description, cyanoacetate (II) represented by a formula shown in the description and a dihydropyridine ester (III) represented by a formula shown in the description to a hybrid reaction under solvent-free conditions, and carrying out separation and purification after the reaction is completed, thereby obtaining the substituted cyanoacetate (IV) represented by a formula shown in the description. According to the method, aldehydes, cyanoacetate and dihydropyridine esters serve as raw materials for the first time, and the substituted cyanoacetate can be efficiently synthesized through a one-pot method reaction without solvents and catalysts, so that the preparation method is simple, efficient and environmentally friendly. 本发明公开了种取代氰基乙酸酯的无溶剂制备方法，其特征在于：包括以下步骤：取醛类化合物(Ⅰ)、氰基乙酸酯(Ⅱ)和二氢吡啶