The development of green and sustainable processes using naturally occurring biopolymers is becoming one of the suitable remedies to replace the conventional catalytic systems that generate large amount of byproducts with high risk factors. In this context, although Knoevenagel-Doebner condensation reaction has been reported with many organocatalysts including proline, no attempts were made to develop heterogeneous catalysts with environmental concerns. Considering these factors in mind, the title reaction is studied with chitosan as a heterogeneous solid base catalyst for the synthesis of α,β-unsaturated carboxylic acids through the condensation followed by decarboxylation reactions. Chitosan offers many advantages including high stability as evidenced by leaching, reusability tests, wide substrate scope and providing higher yields of the desired products with high purity. Powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscope (SEM) and elemental analysis revealed that there are no major changes in the structural integrity and morphology of chitosan before and after catalysis under the optimized reaction conditions.

使用天然存在的生物聚合物开发绿色和可持续性工艺正成为替代传统催化系统的合适方法之一，传统催化系统会产生大量具有高风险因素的副产物。在这种情况下，尽管已经报道了Knoevenagel-Doebner与包括脯氨酸在内的许多有机催化剂的缩合反应，但未尝试开发涉及环境问题的多相催化剂。考虑到这些因素，以壳聚糖为多相固体碱催化剂研究了标题反应，该反应通过缩合然后脱羧反应合成α，β-不饱和羧酸。壳聚糖具有许多优势，例如浸出，可重复使用性测试，广泛的底物范围，并以更高的纯度提供所需产品的更高产量。粉末X射线衍射（XRD），傅立叶变换红外光谱（FT-IR），扫描电子显微镜（SEM）和元素分析表明，在优化反应条件下，催化前后壳聚糖的结构完整性和形态没有重大变化。情况。