Synthesis Of Conjugated Dienes And Polyenes Via Carbonyl Olefination And Barbier-Type Reaction Promoted By Neodymium

The thesis includes two parts: synthesis of conjugated dienes and polyenes via carbonyl compound with Grignard reagent and rare earth metal neodymium is taked part in Barbier-type of reaction.1. Synthesis of conjugated dienes and polyenes via carbonyl compound with Grignard reagent. Olefins is the most common and representative compound in organic reactions. Especially conjugated alkenes not only occupy an important place in the synthesis of many compounds, but also are found in the fragment of numerous natural products. In this paper, we explore a way that α, β- unsaturated ketones and unsaturated aldehydes can reaction with kinds of Grignard reagent to obtain conjugated olefins. When α, β- unsaturated ketones reaction with different group of Grignard reagents, we get conjugated dienes, when unsaturated aldehydes reaction with Grignard reagents, we obtain conjugated trienes and conjugated tetraenes. The reaction has simple operation and mild conditions, the maximum yield can reach 95%.2. Neodymium as a rare earth metal also has important research value, which is tend to lose electrons, they take part in number of reactions due to their distinct chemically active. This paper studies Barbier-Type reaction promoted by neodymium. No matter using allyl chloride or allyl iodide, the reaction can give the corresponding alcohol, a wide range of substrate and can be extended to aldehydes, ketones and esters. Therefore, this approach is conveniently conducted under gentle conditions in a one-pot fashion with high yield.