基于反应控制理念的均相催化和合成体系多样化设计研究

Rational design of catalytic system with the concept of reaction-controlling was developed with the aid of an "intelligent material" that has a regular and characteristic change on its physical and chemical properties during the reaction, offering us an effective means for implementing the purposive intervention on the catalytic system. The key of designing a catalytic system with the reaction controlled strategy is to find a suitable "intelligent material". On the basis of reaction-controlled strategy, this proposal will focus on the following studies: (i) Designing a catalytic system with reaction-controlled biphasic-to-monophasic tunable solvent system base on the fact that esterification of fatty acid and glycerol displayed generally a clear inductive period; In the beginning, the reaction mixture is biphasic because fatty acid is immiscible with glycerol; Due to the occurrence of esterification between fatty acid and glycerol that provides glyceryl monoester, which can act as surfactant, the reaction mixture was changed gradually from biphasic to monophasic during the reaction; Because of the solubilities of substrates are highly different in biphasic system in the beginning stage, the possible side-reaction was inhibited, so that the selectivity to the desired product was improved; (ii) Developing reaction-controlled homogeneous catalytic system with acid-base co-catalyst based on using ammonium hydrogen oxalate as catalyst; At low temperature, ammonium hydrogen oxalate can act as an acid catalyst that initiates decomposition of acetal, providing an aldehyde; Then the reaction temperature was increased to a specified degree that enables thermal decomposition of ammonium hydrogen oxalate, providing an organic amine that can catalyze the following downstream reaction as a base catalyst; (iii) Ionic liquid-supported reaction-controlled phase-transfer organic synthesis; This protocol was designed by using a protic imidazolium-based ionic liquid as supporting material, which allowed us to control the immiscibility of the ionic liquid with water by means of using the reversible aza-Michael reaction of the ionic liquid as a switch; With this strategy, the ionic liquid could be recycled after accomplishing synthesis of the desired product.

借助反应控制策略进行催化体系合理设计的方法立足于具有特定性质的"智能材料"，借助其在反应过程中物化性质发生规律性的变化实现催化体系的人为干预与控制。从事该理念研究的关键在于适宜"智能材料"的开发。本项目拟立足于反应控制理念从事以下研究：（i）借助脂肪酸与丙三醇酯化反应存在明显诱导期的现象设计反应控制双/单变相催化合成体系，反应过程中体系逐步由双相变为单相，因为底物在前期两相体系中的溶解度不同，可能发生的副反应被抑制，选择性得以改善；（ii）以草酸氢铵盐为催化剂发展反应控制均相酸碱共催化体系，草酸氢铵盐在低温下为酸催化剂催化缩醛分解，在高温下则分解放出有机胺，后者可作为碱催化剂催化后续下游反应；（iii）离子液体支载的反应控制相转移有机合成，以质子化咪唑盐离子液体为载体，借助其参与aza-Michael反应的可逆性作为控制离子液体亲疏水性的开关，在实现目标产物合成的同时完成离子液体回收。

为了满足化学合成过程多样、复杂和绿色的需求，本项目立足于化学反应体系关键组分与催化剂之间的协同作用基础，研究设计具有一定反应条件响应能力的“智能化”催化剂，特别是开发具有绿色、可回收特点的催化剂。为了实现催化体系“智能化”的目标，我们首先从均相催化体系中关键组分与主催化剂之间协同作用入手，研究助催化剂、溶剂等组分对催化剂性能的影响，特别关注于助剂协助的酸-酸催化串联过程、酸催化中的助催化剂对底物的活化和反应选择性提高的机制，以期获得具有条件响应能力催化体系“智能化”设计的理论基础。在此基础上，我们在催化体系“智能化”设计方面做了以下两方面的探索：（i）具有液-液分域功能的酸性催化剂；立足于极性非质子溶剂对碳正离子的稳定化作用，设计制备含砜基磺酸功能化离子液体，并以之为具有分域功能的节溶剂型离子液体催化剂，在不使用不绿色溶剂前提下实现了多种重要的有机转化反应；（ii）溶剂调控均相催化剂的固载和回收；借助可逆反应设计了“智能型”两性咪唑盐缚酸剂，实现了部分有机溶剂体系中均相质子酸催化剂的回收再利用；借助低温共熔现象设计了胆碱湿附固体酸催化剂，利用在反应过程中于催化剂表面形成两亲性低温共熔体提高了无水条件下的碳水化合物制备HMF的选择性。本项目在执行过程中一共发表SCI收录论文33篇，申请（授权）中国发明专利3件，参与完成专著章节一部。上述的结果在发表后得到了国际同行的广泛关注，部分结果被选择为当期杂志的封面、hot paper或者被他刊点评，部分论文入列ESI高被引论文（见图15）。项目负责人获得2014年的RSC top 1%作者奖，并连续多年入列（爱思唯尔）中国化学工程领域高被引学者榜单。本项目培养博士研究生5人，硕士研究生7人。项目负责人于2014年、2016年先后两次作为中方主席之一组织召开了中法双边绿色化学学术交流会议；项目组成员多次参加国际、国内学术交流会议。