Abstract Carbon-based catalysts are gained significant interest for improving a number of catalytic processes due to their unique set of benefits. However, a few of such catalysts are proper for synthesis of organic compounds in water. Therefore, there is a strong need for developing water-tolerant and dispersible catalysts. Here, we demonstrate a simple and efficient method for the preparation of highly dispersible phosphonic acid functionalized carbocatalyst. The applied functionalization method was flexible in controlling the functionalization level. The prepared nanocatalyst exhibited superior catalytic performance toward multicomponent synthesis of pyrano[2,3-c]pyrazole, with 80–90% yield within 15 min in water. Moreover, this water-tolerant solid acid catalyst could be simply retrieved and after 6 successive cycles of reactions, the reaction time and yield still keeps within the same level.

中文翻译：

---

磷酸功能化氧化石墨烯：一种用于绿色合成生物活性吡唑的高分散性碳基纳米催化剂

摘要 碳基催化剂由于其独特的一系列优点，在改进许多催化过程方面引起了极大的兴趣。然而，一些此类催化剂适用于在水中合成有机化合物。因此，迫切需要开发耐水和可分散的催化剂。在这里，我们展示了一种简单有效的制备高分散性膦酸功能化碳催化剂的方法。应用的功能化方法在控制功能化水平方面是灵活的。所制备的纳米催化剂对吡喃并[2,3-c]吡唑的多组分合成表现出优异的催化性能，在水中15分钟内产率为80-90%。此外，这种耐水固体酸催化剂可以简单地回收，经过 6 个连续的反应循环后，