| Allyl alcohol,allyl amine and their derivatives are important intermediates in organic synthesis.Palladium-catalyzed allylation to achieve such compounds plays an important role in natural product synthesis and drug synthesis.In this work,new methods for allylic compounds synthesis by palladium-catalysis are described.The main content is summarized below:1.A new type of three-component reaction catalyzed by palladium,using benzyl halides, allyltributyltin and activated olefines was developed.In the past,similar compounds were synthesized by the radical reaction,but the reaction conditions were not mild and had low functional group compatibility,so a lot of materials were wasted.These conditions do not meet the requirements of modern environmentally conscious chemistry.In this paper,it was found that in the presence of 5 mol%Pd(PPh3)4 and THF as solvent,reasonable to moderate yields were obtained at 50°for 24 h.The dearomatization product and Stille coupling product were not observed.The developed method was carried out with simple operation under mild conditions.2.In this paper,the nucleophilic addition reactivity ofπ-propargyl,π-allyl palladium intermediate to aldehydes,ketones and imines was investigated.It was found that only theπ-allyl group could undergo nucleophilic addition to produce homoallyl alcohols and amines. Best yields were obtained when 5 mol%Pd2(dba)3 and 10 mol%propargyl bromide were used. This method showed a good addition reactivity of aldehyde,imine,even ketone and unsaturated ketone.The discipline of reactivity ofπ-propargyl,π-allyl palladium intermediate with aldehyde,imine is further revealed herein.
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