A novel magnetic inorganicâorganic nanohybrid material H6P2W18O62/pyridino-Fe3O4 (HPA/TPI-Fe3O4) was fabricated and performed as an efficient, eco-friendly, and highly recyclable catalyst for the solvent-free, one-pot, and multi-component synthesis of various substituted 1-amidoalkyl-2-naphthols from the reaction of β-naphthol, an aldehyde, and benzamide with good to excellent yields (47â94%) and in a short span of time (25â60 min). The nanohybrid catalyst was prepared by the chemical anchoring of WellsâDawson heteropolyacid H6P2W18O62 onto the surface of modified Fe3O4 nanoparticles with N-[3-(triethoxysilyl)propyl]isonicotinamide (TPI) linker. The magnetically recoverable catalyst was easily recycled at least eight times without any loss of catalytic activity. XRD, TEM, UV-vis, and FTIR confirmed that the heteropolyacid H6P2W18O62 is well dispersed on the surface of the solid support and its structure is retained after immobilization on the pyridine modified Fe3O4 nanoparticles. This protocol is developed as a safe and convenient alternate method for the synthesis of 1-amidoalkyl-2-naphthols utilizing an eco-friendly, and a highly reusable catalyst.
制备了一种新型磁性无机-有机纳米杂化材料H6P2W18O62/
吡啶基-
Fe3O4 (HPA/
TPI- ),并作为一种高效、环保、高度可回收的催化剂,用于无溶剂、一锅法和多用途催化剂。由β-
萘酚、醛和苯甲酰胺反应合成各种取代的 1-酰胺基烷基-
2-萘酚,产率从良好到优异 (47-94%),且时间跨度短(25-60 分钟) )。该纳米杂化催化剂是通过将 Wells-Dawson 杂多酸 H6P2W18O62
化学锚定到带有 N-[3-(三乙氧基甲
硅烷基)丙基]异烟酰胺 (
TPI) 连接体的改性 纳米颗粒表面来制备的。可磁性回收的催化剂可以轻松回收至少八次,而不会损失任何催化活性。 XRD、
TEM、UV-vis 和 FTIR 证实杂多酸 H6P2W18O62 良好分散在固体载体表面,固定在
吡啶修饰的 纳米粒子上后其结构保留。该方案被开发为一种安全、方便的替代方法,利用环保且高度可重复使用的催化剂合成 1-酰胺基烷基-
2-萘酚。