A new organosilane precursor has been designed via VilsmeierâHaack formylation of phloroglucinol followed by its Schiff base condensation with 3-aminopropyl-triethoxysilane (APTES). A novel organicâinorganic hybrid periodic mesoporous organosilica (PMO) LHMS-3 containing the highly coordinating bis(propyliminomethyl)-phloroglucinol moiety inside the pore wall has been synthesized by using this precursor organosilane molecule. Phenolic-OH and imine-N donor sites present in this PMO material have been utilized to anchor Pd(II) species at the surface of the mesopores. Small angle neutron scattering, XRD, HR TEM, SEM, 13C and 29Si solid state MAS NMR, UV-vis and FT IR spectroscopic tools are utilized to characterize the 2D-hexagonal mesophase and the presence of the bis(propyliminomethyl)-phloroglucinol moiety inside the pore wall. This Pd-anchored material Pd-LHMS-3 showed excellent catalytic activity and trans-selectivity in Heck CâC bond formation reactions for the synthesis of a series of value-added aromatic and aliphatic olefins.
一种新的有机
硅烷前驱体通过
对酚羟基酸(phloroglucinol)进行Vilsmeier-Haack醛化反应,随后与3-
氨基丙基三乙氧基
硅烷(AP
TES)进行席夫碱缩合反应而设计合成。利用该有机
硅烷前驱体合成了一种新型的有机-无机杂化周期性介孔有机
硅材料(PMO)L
HMS-3,含有高配位性的双(丙基亚
氨基甲基)-
酚羟基酸基团嵌入孔壁内。该PMO材料中的
酚羟基-OH和
亚胺-N供体位点被用来在介孔表面锚定Pd(II)物种。采用小角中子散射、X射线衍射、HR透射电子显微镜、扫描电子显微镜、13C和29Si固体核磁共振、紫外-可见光及傅里叶变换红外光谱等工具对该2D-六角介相及孔壁内的双(丙基亚
氨基甲基)-
酚羟基酸基团进行了表征。这种Pd锚定材料Pd-L
HMS-3在Heck C-C键形成反应中表现出优异的催化活性和反式选择性,可用于合成一系列附加值的芳香族和脂肪族烯烃。