In this article, the synthesis of a novel and highly efficient recyclable and reusable heterogeneous nanocatalyst has been reported via the functionalizing of the Fe₃O₄‐magnetized graphene oxide nanosheets with the N₆‐Schiff base Cu (II) complex (GO/Fe₃O₄@SPNC). The structure of this novel nanocatalyst was determined by different analytical techniques such as FTIR, FE‐SEM, TEM, TGA‐DTG, and VSM. The catalytic activity of the synthesized GO/Fe₃O₄@SPNC nanocatalyst was explored for the synthesis of several new 2H‐pyrido[3′,2′:6,7]pyrano[2,3‐d]pyrimidine‐7‐carbonitrile derivatives with excellent yields. All new derivatives were fully identified by various spectral (¹H NMR, ¹³C NMR, FT‐IR, ESI‐MS) analyses. In addition, this nanocatalyst carried out satisfactory catalytic maintenance of activity and high chemical stability in the titled reactions after seven‐time of recycling without substantial loss of leaching.

中文翻译：

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异质磁性氧化石墨烯支持的N6-席夫碱铜（II）配合物是用于合成新的吡啶并[2,3-d]嘧啶-7-腈衍生物的纳米催化剂

在本文中，已经报道了通过将Fe ₃ O ₄磁化的氧化石墨烯纳米片与N ₆席夫碱铜（II）配合物（GO / Fe）官能化，合成了新型且高效可回收和可重复使用的多相纳米催化剂。₃ O ₄ @SPNC）。这种新型纳米催化剂的结构是通过不同的分析技术确定的，例如FTIR，FE-SEM，TEM，TGA-DTG和VSM。探索了合成的GO / Fe ₃ O ₄ @SPNC纳米催化剂的催化活性，以合成几种新的2 H-吡啶并[3'，2'：6,7]吡喃并[2,3- d] pyrimidine-7-腈衍生物，收率极高。所有新衍生物均通过各种光谱分析（¹ H NMR，¹³ C NMR，FT-IR，ESI-MS）进行了全面鉴定。此外，这种纳米催化剂经过七次循环使用后，可以在标题反应中实现令人满意的催化活性维持和高化学稳定性，而没有明显的浸出损失。