The Study And Application Of Supramolecular Iminium Catalysis In Vinylogous Michael Reaction

some supplements and exploration about "Hydrogen-Bond-Mediated Supramolecular Iminium Catalysis" of Vinylogous Michael reaction was described in this thesis, Meanwhile the study and application of a new type of combined reagents "LJX+NS-2" at floation is developed. The thesis is divided into two parts.Part1:the development and application of Hydrogen-Bond-Mediated Supramolecular Iminium Catalysis in Vinylogous Michael reactionAsymmetric organic catalysis, as an important branch in organic chemistry, has already been applied and researched in a lot of new reactions, and promoted the development of the modern organic synthesis. However, the current research in the field of asymmetric organocatalysis has be.e.n hampered by several limitations, such as long reaction time, high catalyst loading, low reactivity and so on. To this end, Our group developed the concept of "Hydrogen-Bond-Mediated Supramolecular Iminium Catalysis", it can significantly improve the activity of catalyst through reducing LUMO energy to shorten the reaction time and reduce the loading of catalyst, at the same time a wide variety of catalysts can be used to control the selectivity of reactions. Owing to the poor reactivity and difficulty of controlling regioselectivity, the development of direct vinylogous Michael additions using linear nucleophilic substrates is a long-standing challenge. By employing a carefully and rationally designed multifunctional supramolecular iminium catalysis strategy, we reported herein the first direct vinylogous Michael addition of unmodified linear nucleophilic vinylogous substrates with a,(3-unsaturated aldehydes affording valuable chiral1,7-dioxo compounds with good yields and excellent regio-as well as enantioselectivity. Conceptually, this is an attractive strategy for expanding the capabilities of supramolecular iminium catalysis and has the potential to be a useful platform for studying how non-covalent interactions between ion pairs give rise to selectivity. The multiple-activation strategy should provide new insight into designing new reactions and solving other existed elusive problems. Part2:the development and application of a new flotation reagent combination "LJX+NS-2"As the critical aspect of the flotation among the chemical flotation, flotation reagents have a pivotal position in mineral processing industries. The progress and development of flotation technology are dependent on the development and application of flotation reagent to a large degree. The content of the nickel sulfide in Jinchuan nickel mine which is one of China’s three most metal Ore ranking second in the world, So in Jinchuan nickel sulfide mine, the development of a new type of highly efficient flotation reagents to improve the sorting index of Jinchuan nickel sulfide ore is of great scientific significance and application value. The imine compounds LJX with O,S atom synthesized in this thesis were used to be the combination of new type of the mineral processing reagents with the adjusting agent "NS-2". The results of the comparative experiment taken between the new regent combination "HHN+NS-2" and J-622, show that the new regent combination cannot only improve the separation results and reduce tailings grade and the MgO content of concentrate, but also greatly increase the nickel and copper recovery. It has a very good industrial promotion prospects, also formed a huge economic and social benefits.