Preparation of Al2O3-SO3H and nano Al2O3-SO3H as a heterogeneous catalyst for the one-pot tree component synthesis of Hexahydroquinazolinone

An efficient and practical synthetic method has been developed for the preparation of hexahydroquinazolinone derivatives via a one-pot three-component catalytic reaction. The method involves the reaction of various aldehyde derivatives with urea and 1,3-cyclohexadiene in the presence of Al 2 O 3 -SO 3 H and nano Al 2 O 3 -SO 3 H, which serve as effective heterogeneous acid catalysts. These catalysts exhibited excellent performance under thermal conditions, affording the desired products in high purity and excellent yields within short reaction times. This process offers several notable advantages, including operational simplicity, minimal purification steps, and the use of inexpensive and readily available catalysts. Moreover, the products were easily purified by crystallization, and the catalysts proved to be reusable over multiple cycles without significant loss of catalytic activity or efficiency.