Water-compatible reactions of sp carbon-hydrogen bonds

The research includes two parts: water-compatible catalytic reactions of sp C-H bonds and one-step synthesis of tetrahydroquinolines.; Part one. Catalytic reactions of sp C-H bonds. Section 1. A copper-free palladium acetate catalyzed-coupling reaction of terminal alkynes with aryl halides with a commercial available phosphine ligand produced various substituted alkynes in aqueous environment. Section 2. A facile and simple method to generate a variety of conjugated enynes from terminal alkynes and electron-deficient alkynes by using a combination of Cu/Pd together with common ligand, PPh3, in water and under an air atmosphere was investigated. Section 3. The first palladium-catalyzed 1,4-addition of terminal alkynes to C=C double bond of conjugated enones was developed in water and in acetone, and under an air atmosphere. The corresponding gamma, delta-alkynyl ketones were obtained in high yields. The process is simple and can be generated a wide range of alkynyl ketones. The preliminary mechanism was investigated via isotope experiments. Section 4. A highly effective direct coupling of acid chloride with terminal alkynes was developed in aqueous environment to produce ynones in high yields in the presence of a catalytic amount of PdCl2(PPh3)2 /CuI together with sodium laurylsulfate as the surfactant and K 2CO3 as the base.; Part two. Syntheses of tetrahydroquinolines. Section 1. An efficient and simple method for the synthesis of tetrahydroquinoline derivatives was developed via a solid acidic resin-catalyzed domino reaction of anilines and dihydropyrans in water. No organic solvent was required and no metal-based catalyst was used. The solid resin and the aqueous solvent can be recycled readily. The products have various pharmaceutical applications. Section 2. An efficient and simple method was developed to form tetrahydroquinoline derivatives that have various pharmaceutical applications via a novel domino reaction of nitroarenes and cyclic enol ethers.