Catalytic Oxidative Conversion from Naphthol to 2-Hydroxy-1, 4-naphthoquinone over Iron Porphyrin Catalysts by Molecular Oxygen in an Alkaline 2-Propanol Solution

In an alkaline 2-propanol solution with 5,10,15,20-tetra(4-methoxyl phenyl) porphyrin iron chloride(TOMPPFeCl) as a catalyst and oxygen as a cheap green oxidant, 2-naphthol was conversed to 2-hydroxy-\{1,4-naphthoquinone(HNQ)\} with a yield of 62.17% and a selectivity of 100%, and the conversion number of TMOPPFeCl catalyst was 8.32/min. The catalytic oxidation products were characterized by means of UV-Vis, IR, GC-MS, ~ 1H NMR and melting point determination. In this catalytic oxidation, the catalytic activity of TMOPPFeCl was researched in detail and the reacting conditions were optimized. A possible reaction mechanism is summarized based on in situ EPR determination.

Catalytic Conversion of 2-Naphthol to 2-Hydroxy-1,4-naphthoquinone Under Mild Conditions

2-Hydroxy-1,4-naphthaquinone (HNQ) was selectively synthesized from catalytic oxidation of 2-naphthol by molecular oxygen over tetra(4-methoxyl-phenyl)porphyrinate iron(III) chloride (TMOPPFeCl) catalyst in an alkali methanol solution under mild conditions. The influences of solvents, temperature, time, as well as amounts of cata-lysts and alkali were studied. The quantitative data show that 32.9% of 2-naphthol (0.093 mol/dm3) was catalyti-cally converted to HNQ with the selectivity of 100% at 323 K for 9 h over TMOPPFeCl catalyst (2.54×10-4 mol/dm3) in alkali media (30 mL of methanol containing 2.5 mol/dm3 of NaOH) by flowing molecular oxygen (flowing rate of 45 mL/min).

铁卟啉催化氧化萘酚合成2-羟基-1,4-萘醌

以铁卟啉为催化剂在碱性甲醇溶液中 ,可用 H2 O2 将 α-或 β-萘酚高选择性氧化为 2 -羟基 -1 ,4 -萘醌( HNQ) ,最高产率达 57% .产物用 IR,UV-Vis,MS,NMR,熔点测定和元素分析等方法表征 .采用气相色谱法对催化体系监测 ,证明产物纯度为 95% .在碱性水溶液中 ,利用 HNQ在 4 52 nm的特征吸收 ,建立了 UV-Vis定量分析产物的方法 ,探讨了 Na OH浓度对 HNQ吸收值的影响 ,测定了共存物的干扰量 .