The present work deals with a catalytic application of aluminized polyborate as a mild solid acid catalyst for multicomponent synthesis of 1,8‐dioxo‐octahydroxanthenes under solvent‐free condition at 100°C‐110°C. It involves selective domino Knoevenagel‐Michael reaction of 1 mole of aromatic aldehyde with 2 moles dimedone. The aluminized polyborate is simply synthesized by using boric acid and aluminum trichloride and characterized by FT‐IR, XRD, SEM and EDAX techniques. The mild Lewis acidity, crystalline solid nature, stability and recyclability are significant features of the catalyst. The solvent‐free condition, clean reaction profile, inexpensive and non‐toxic catalyst, operational simplicity, good to excellent product yields, reduced reaction time and applicability to wide range of substrate are crucial features of this protocol.

中文翻译：

---

使用环保的铝化多硼酸盐催化剂快速简便地合成无溶剂的1,8-二氧-八氧杂蒽

本工作涉及在无溶剂条件下于100°C-110°C下将铝化多硼酸盐作为一种温和的固体酸催化剂的催化应用，用于多组分合成1,8-二氧代-八氢氧杂蒽。它涉及1摩尔芳族醛与2摩尔二甲基酮的选择性多米诺Knoevenagel-Michael反应。镀铝的多硼酸盐是使用硼酸和三氯化铝简单合成的，并通过FT-IR，XRD，SEM和EDAX技术进行了表征。温和的路易斯酸度，结晶固体性质，稳定性和可循环性是催化剂的重要特征。该方案的关键特征是无溶剂条件，清洁的反应曲线，廉价且无毒的催化剂，操作简便，优良的产品收率，缩短的反应时间以及适用于多种底物。