4,4′,4′′–三膦酸甲酯三苯胺的合成及应用

Synthesis and application of hexamethyl (nitrilotris(benzene-4,1-diyl))tris(phosphonate)

摘要:

以三苯胺为原料，通过亲电取代反应制备得到中间体4,4′,4′′–三碘代三苯胺（TITPA），该中间体与亚磷酸三甲酯在Pd(PPh3)2Cl2催化下经Arbuzov重排得到目标产物4,4′,4′′–三膦酸甲酯三苯胺（TPTPA）。通过1HNMR、13CNMR、31PNMR、高分辨质谱和元素分析对目标产物进行了结构表征，并考察了催化剂种类与用量、反应温度、反应时间对目标化合物产率的影响。结果表明，最佳合成条件为： n（Pd(PPh3)2Cl2）∶n（TITPA）= 0.18∶1.00，反应温度150℃，反应时间5h。在该条件下，目标产物TPTPA的收率可达82.5%。接着，TITPA用于PVC的阻燃改性。结果表明，当TPTPA添加量为10%（以PVC树脂的质量为基准，下同），样品的极限氧指数可达29.6%、UL94垂直燃烧达V-0级，且力学性能保持良好。。

Abstract:

Tris(4-iodophenyl)amine (TITPA) was synthesized using triphenylamine as raw material through electrophilic substitution reaction. Subsequently, a classic Arbuzov rearrangement reaction between intermediate TITPA and trimethyl phosphite was performed in a catalytic amount of Pd(PPh3)2Cl2 to obtain hexamethyl [nitrilotris(benzene-4,1-diyl)]tris(phosphonate) (TPTPA). The target product was characterized by 1HNMR、13CNMR、31PNMR、HR-MS and elemental analysis. The effects of catalyst type, catalyst dosage , reaction temperature and reaction time on the yield of the target compound were investigated. The results showed that the optimum conditions were obtained as follows: n(Pd(PPh3)2Cl2)∶n(TITPA) = 0.18∶1.00, reaction temperature of 150 ℃, reaction time of 5 h. Under these conditions, the yield of hexamethyl [nitrilotris(benzene-4,1-diyl)]tris(phosphonate) could reach 82.5%. Subsequently, TPTPA as a flame retardant was used for flame retardant modification of PVC. The results indicated that the prepared sample with an additive amount of TPTPA of 10% (based on the mass of PVC resin, the same below) had limited oxygen index of 29.6% and vertical combustion test of UL94 up to V-0 level as well as maintained excellent mechanical properties.