Study On Transition-metal-catalyzed Carbon-Carbon Bonds Formation Reactions In PEG-400/H₂O

This dissertation consists of three parts:Part one: We investigated Sonogashira coupling reaction of terminal alkynes with aryl iodides catalyzed by NiCl2(PPh3)2/CuI in a mixture of PEG-400 and H2 O as green solvent. The results showed that in the presence of NiCl2(PPh3)2 and CuI, Sonogashira coupling reaction of terminal alkynes with aryl iodides proceeded smoothly in PEG-400/ H2O(3:2) at 100 oC with potassium carbonate as base to afford a variety of aromatic internal acetylenes in high yields. Moreover, NiCl2(PPh3)2/CuI/PEG-400 catalytic system can be recycled and reused four times without significant loss of catalytic activity, which providing a novel, practical and green route to aromatic internal acetylenes.Part two: We investigated [RuCl2(p-cymene)]2-catalyzed tandem oxidative alkenylation/ Michael addition reaction of substituted benzoic acids with alkenes in PEG-400/H2O(3:2) as green solvent. The results showed that in the presence of [RuCl2(p-cymene)]2 and Cu(OAc)2·H2O, the tandem oxidative alkenylation/ Michael addition reaction of substituted benzoic acids with alkenes proceeded smoothly in PEG-400/H2O(3:2) at 100 oC to afford a variety of phthalide derivatives in high yield. The [RuCl2(p-cymene)]2/Cu(OAc)2/PEG-400/H2 O catalytic system can be recycled and refused for four times without any decrease in reaction efficiency, which providing a green and simple process for the preparation of phthalide derivatives.Part three: We investigated PdCl2(PPh3)2-catalyzed addition reaction of alkynes with sodium tetraphenylborate or arylboronic acids in the PEG-400/H2O(1:1) as green solvent under argon. The reaction afforded phenyl aromatic alkenes compounds in good yields at the room tempurature. The PdCl2(PPh3)2/PEG-400/H2 O catalytic system can be recycled and refused for many times without significant loss of catalytic activity, which serve as a practical way to synthesize aromatic alkenes compounds.