One-Pot Halogenation-Heck Coupling Reactions in Ionic Liquids

Abstract

Traditional cross-coupling approaches rely upon two steps - halogenation and coupling - each of which is viewed and conducted independently. In an effort to develop a one-pot ­approach, we have noted that the halogenation and Heck coupling reactions can both be conducted in a room-temperature ionic liquid without the need to isolate the halogenated intermediate. Application to several systems shows that this approach works well for moderately to highly electron-rich aromatics.

Key words

cross-coupling - Heck coupling - room-temperature ­ionic liquids

References and Notes

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7

It is worth noting that the regioselectivity reported for these halogenations in RTILs is also quite high. In the halogenation-couplings reported in this work, no trace of any regioisomeric products could be detected by ¹H NMR.

9

All of the products reported exhibit spectral properties consistent with those reported in the literature.