A novel carbohydrate-based catalytic composite was prepared through covalent decoration of cross-linked chitosan beads with a cyclodextrin nanosponge. In this regard, chitosan beads were fabricated and cross-linked with glutaraldehyde. Subsequently, they were reacted with an amino-functionalized cyclodextrin nanosponge. The resultant composite was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, thermogravimetric analysis, and elemental mapping analysis. Then the performance of the metal-free catalyst for promoting ultrasonic-assisted synthesis of dihydropyrimidinones and octahydroquinazolinones in aqueous media was appraised. It was found that the composite was highly efficient and recyclable. Moreover, the activity of the composite was superior to that of its individual components. It is assumed that incorporation of the cyclodextrin nanosponge, which has high capability for the formation of an inclusion complex in the structure of the composite, allows the catalyst to act as a molecular nanoreactor and promotes the reactions efficiently in aqueous media.

通过用环糊精纳米海绵对交联的壳聚糖珠进行共价修饰，制备了一种新型的基于碳水化合物的催化复合材料。在这方面，壳聚糖珠粒被制造并与戊二醛交联。随后，它们与氨基官能化的环糊精纳米海绵反应。通过傅立叶变换红外光谱，X射线衍射，扫描电子显微镜，能量色散X射线光谱，热重分析和元素图谱分析对所得复合材料进行表征。然后评估了无金属催化剂在水性介质中促进超声辅助合成二氢嘧啶酮和八氢喹唑啉酮的性能。发现该复合材料是高效和可回收的。而且，复合材料的活性优于其单个组分的活性。假定掺入具有在复合材料的结构中形成包合配合物的高能力的环糊精纳米海绵，可使催化剂充当分子纳米反应器并在水性介质中有效地促进反应。