A Convenient Synthesis of 1,4-Disubstituted Isoquinolines by Reactions of α-Substituted 2-Lithio-β-methoxystyrenes with Nitriles

Abstract

It has been found that halogen-lithium exchange between α-substituted 2-bromo-β-methoxystyrene derivatives and n-butyllithium generates α-substituted 2-lithio-β-methoxystyrene derivatives, which successfully react with a range of nitriles to afford the corresponding 1,4-disubstituted isoquinolines in reasonable yields.

Key words

benzyl anion - isoquinoline - nitrile - organolithium - styrene

References

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8

A possibility of the formation of 3 via 6π electrocyclization of 4 followed by elimination of lithium methoxide cannot be excluded.