Unsymmetrical 1,2,5,6-tetrahydropyridine-3-carboxylates were obtained for the first time from a five-component Fe3O4@TDSN-Bi(III)-catalyzed reaction of aryl aldehydes, aryl amines, and ethyl acetoacetate. This magnetically separable catalyst enabled the selective incorporation of two different aryl amines or two different aryl aldehydes into the product, and provided excellent yields, short reaction times, mild reaction conditions, satisfactory catalyst recyclability, and low catalyst loading.

中文翻译：

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固定在三嗪树枝状大分子稳定的磁性纳米粒子上的Bi（III）催化对称和不对称四氢吡啶的非对映选择性合成。

首次从五组分Fe3O4 @ TDSN-Bi（III）催化的芳基醛，芳基胺和乙酰乙酸乙酯的反应中获得不对称的1,2,5,6-四氢吡啶-3-羧酸酯。该磁性可分离的催化剂能够将两种不同的芳基胺或两种不同的芳基醛选择性地掺入产物中，并提供优异的收率，较短的反应时间，温和的反应条件，令人满意的催化剂可回收性和较低的催化剂负载量。