Facile and Selective Cleavage of Allyl Ethers Based on Palladium(0)-Catalyzed Allylic Alkylation of N,N′-Dimethylbarbituric Acid

Abstract

The classical palladium(0)-catalyzed allylic alkylation of N,N′-dimethylbarbituric acid can be applied to the facile and selective cleavage of allylic alkyl ethers to release the corresponding alcohols in excellent yield. This reaction proceeds under neutral conditions without any additive to activate the allyl ethers and tolerates various functional groups, such as ester, ether, ketone, alkyl and aryl chloride, nitrile and nitro groups.

Key words

N,N′-dimethylbarbituric acid - carbonucleophiles - palladium(0)-catalyzed allylic alkylation - cleavage of allyl ethers - high chemoselectivity

References

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13

The use of Meldrum’s acid (pK_a = 5.2) led to decomposition of 6 and gave no deallylated product 7. Although unsubstituted barbituric acid (pK_a = 4.1) has poor solubility in THF, it could also be used for 1.

14

Other palladium catalysts, i.e. Pd(OAc)₂-PPh₃ and Pd₂(dba)₃-PPh₃, gave similar results.