Synthesis of 1, 3, 5-trisubstituted-4,5-dihydro-1H-pyrazole catalyzed by vitamin B1 and its fluorescence properties
作者:Dawei Zhang、Lu Ren、Ailing Liu、Yumin Zhang、Yang Lv、Qiang Gu
DOI:10.1007/s11164-021-04655-9
日期:2022.3
Abstract An efficient synthesis of 1,3,5-trisubstituted-1H-pyrazoles was developed via cyclocondensation in 78–92% yields starting from α,β-unsaturated aldehydes/ketones with substituted phenylhydrazine using vitamin B1 as a catalyst, and was characterized by HR-MS, FT-IR, 1H NMR and 13C NMR spectroscopy. The reaction has simple operation, metal-free catalysis, acid or base free catalysis. As a green
摘要 1,3,5-三取代-1 H-吡唑的高效合成是通过以维生素 B 1为催化剂的α , β-不饱和醛/酮与取代苯肼开始的缩合反应,收率为 78-92% ,并对其进行了表征通过 HR-MS、FT-IR、1 H NMR 和13 C NMR 光谱。该反应操作简单,无金属催化,无酸或碱催化。作为一种绿色催化剂,维生素B 1被发现具有良好的催化活性和缩合反应的可重复使用性。1,3,5-三取代-1 H当吸电子基团与苯乙酮相连时,-吡唑在不同溶剂中呈现橙红色至青色(以化合物5i为例)。化合物5i作为金属离子荧光探针对Ag +检测具有优异的选择性。化合物3-(4-氯苯基)-1,5-二苯基-4,5-二氢-1H-吡唑( 5b )的晶体结构呈正交空间群Pca 21并形成外消旋晶体。 图形概要