苯并噁嗪-异腈三组分反应及其在聚合物构筑方面的应用研究

【作者】 张杰；

【导师】 石伟；

【作者基本信息】 西南石油大学 ， 化学工程与技术， 2019， 硕士

【摘要】 作为一类新型的改性酚醛树脂,基于含N,O六元杂环的苯并噁嗪类化合物具有反应原料丰富、分子设计灵活、合成过程无需外加特殊催化剂、固化过程体积收缩率低且无有毒小分子释放及固化树脂具有优异综合性能等优点,因而吸引了研究者们广泛的关注。但从目前的相关报道可知,关于苯并噁嗪的研究主要集中在将其作为热固性树脂的相关应用方面,而对其自身化学反应活性的研究却鲜有报道。苯并噁嗪具有畸形的椅式构型,使其中所含的六元杂环具有较大的环张力。此外,处于N,O原子之间的亚甲基(-CH2-)由于同时与两个电负性较大的原子相连而被活化。因此,在一定条件下苯并噁嗪六元杂环可发生开环反应而生成具有高反应活性的亚胺类中间体。研究发现,亲核试剂的存在可促进苯并噁嗪发生开环并发生后续的亲核加成反应。从目前报道可知,对于此类苯并噁嗪/亲核试剂之间的反应,除了新兴的苯并噁嗪-巯基反应(COLBERT反应)外,还未有新的相关报道出现。以结构丰富的苯并噁嗪作为反应底物构筑新型化合物的相关研究具有很大的研究空间。异腈具有与巯基相似的亲核性与金属络合性质,其作为多组分反应的重要底物之一在合成化学中发挥了重要的作用。然而,大部分烷烃类异腈化合物所具有的极其难闻的气味严重阻碍了其发展。芳香类异腈化合物虽然在很大程度上抑制了气味问题,但由于异腈-芳环之间的共轭作用使异腈的化学活性有所下降。因此,基于无臭异腈的新型反应的探究可有效的拓展其在合成化学中的应用前景。基于以上研究现状,本课题以探究苯并噁嗪与无臭异腈间的化学反应为出发点,对相关小分子模型反应及其在聚合物构筑方面的应用进行了系统研究,主要的工作包括以下三个部分:(1)以单官能苯并噁嗪/异腈为反应底物,成功开发了一类基于苯并噁嗪、异腈和水的新型三组分反应体系。该反应以辛基磷酸(OPA)为催化剂,在室温条件下即可高效合成酰胺类化合物;(2)在此基础上,利用双官能团苯并噁嗪/异腈化合物为底物成功开发了相应的三组分聚合反应体系。后续研究表明该聚合体系具有反应高效(6 h)、条件温和(室温且无需金属催化)及底物普适性高等优点;(3)合成了含三苯胺基团的功能化异腈单体,将其与双官能苯并噁嗪进行聚合反应,制备出具有电致变色性质的聚合物材料,从而为该聚合反应体系在功能聚合物构筑方面的相关应用提供实施范例。更多还原

【Abstract】 As a new class of modified phenolic resin,benzoxazines are a type of oxygen and nitrogencontaining,six-membered heterocyclic compounds.Benzoxazines have attracted wide attention because of their excellent comprehensive properties,such as abundant starting substrates,high molecular-structure design flexibility,no catalyst required in the synthesis process,near-zero volumetric change and no release of toxic by-products during curing.However,despite the widespread investigation of benzoxazines as thermosetting plastics,scarce attention has been paid to the utilization of the chemical reactivity of the benzoxazine ring up to now.The deformed chair configuration results in a large ring strain for benzoxazines,and the methylene group(-CH2-)between N,O atoms is activated due to the connection with two electronegative atoms.Therefore,the high reactive imine intermediate might be formed by the ring-opening of benzoxazine under some conditions.It has been reported that that nucleophiles could promote the ring-opening of benzoxazines and induce the subsequent nucleophilic addition.Except for the benzoxazine-thiol reaction(COLBERT reaction)reported recently,to our knowledge,there is no report regarding the ring-opening addition reaction of benzoxazines with other nucleophiles.Hence,using benzoxazines as the reaction substrate to construct novel compounds have become a potential researching field.Isocyanides possess similar metal coordination capability and nucleophilicity with thiols,and play a vital role in organic syntheses as one of key substrates in multicomponent reactions.Nevertheless,the main obstacle for the application of isocyanides is their extremely unpleasant odor(for a majority of alkyl isocyanides).Although most of aromatic isocyanides are odorless,the chemical activity decreases due to the conjugation effect between isocyanides and aromatic rings.Thus,the investigation of new reactions based on odorless isocyanides could effectively expand its application prospects in synthetic chemistry.Based on this,we systematically investigated the reaction between benzoxazines and isocyanides,developing corresponding model reaction and its further application in polymer construction.The main work includes the following three parts:(1)Developed a novel three-component reaction with benzoxazines,odorless isocyanides,and water as the starting substrates.The reaction use octylphosphonic acid(OPA)as a catalyst and could efficiently afford amides at room temperature;(2)The corresponding three-component polymerization system had been developed with bifunctional benzoxazines and isocyanides as monomers.The results tells that this polymerization system showed the advantages of high reaction efficiency(6 h),mild reaction conditions(room temperature and metal-free catalyst)and wide substrate adaptability;(3)Functional isocyanides,which containing triphenylamine groups,was synthesized and polymerized with bifunctional benzoxazine to prepare an electrochromic polyamide,providing successful sample for the application of this polymerization system in construction of functional polymers.更多还原