Runpu Shen

Novel Ionic Liquid with Both Lewis and Brønsted Acid Sites for Michael Addition

Ionic liquid with both Lewis and Brønsted acid sites has been synthesized and its catalytic activities for Michael addition were carefully studied. The novel ionic liquid was stable to water and could be used in aqueous solution. The molar ratio of the Lewis and Brønsted acid sites could be adjusted to match different reactions. The results showed that the novel ionic liquid was very efficient for Michael addition with good to excellent yields within several min. Operational simplicity, high stability to water and air, small amount used, low cost of the catalyst used, high yields, chemoselectivity, applicability to large-scale reactions and reusability are the key features of this methodology, which indicated that this novel ionic liquid also holds great potential for environmentally friendly processes.

Synthesis of novel acidic ionic liquid immobilized on silica

A novel acidic ionic liquid immobilized on silica has been synthesized by hydrolyzing tetraethyl orthosilicate (TEOS) and the acidic ionic liquid derived from (3-aminopropyl) trimethoxysilane. The catalytic activities were evaluated in the acetalization and biodiesel synthesis. The results showed that the solid acid was a very efficient catalyst for the traditional acid-catalyzed reactions with the yield over 99.0%. A novel solid acid combined both the high activities inherent to the acidic ionic liquid and the feasibility of separation of the solid catalysts. High acidity, enhanced catalytic activities and improved stability were the key properties of the novel solid acid.

An Efficient Synthesis of Spiro[indoline-3,9′-xanthene]trione Derivatives Catalyzed by Magnesium Perchlorate

A simple and efficient method for the synthesis of spiro[indoline-3,9′-xanthene]trione derivatives by means of condensation between isatins and 1,3-cyclohexanedione in the presence of a catalytic amount of magnesium perchlorate at 80 °C in 50% aqueous ethanol medium has been described. Notably, the present method offers desirable advantages of good yields, simplicity of workup procedure, easy purification, and reduced reaction times.

Practical Synthesis of Lycopene

Carotenoids are a large group of lipid-soluble pigments biosynthesized in plants, in bacteria, in some fungi and in algae. Lycopene is a red pigmented carotenoid found in tomatoes. It contains thirteen double bonds and has a greater radical scavenging ability than b-carotene. It has shown potential as protection against a variety of serious disorders such as some cancers, cardiovascular and degenerative eye diseases. These interesting biological properties as well as its unique molecular structure have stimulated a number of efforts to produce lycopene since its first reported synthesis in 1950, whose the major goal was the design of a method to introduce newly conjugated carbon-carbon double bonds. We previously reported a practical route for the total synthesis of lycopene via a stepwiseC15CC10CC15doubleWittig-Horner reaction, inwhichC15-phosphonate2awas preparedasthekeybuildingblocksstartingfrom4,4-dimethoxy-3-methylbutanal(Scheme 1).