Chemoselectivity-independent Cu-mediated coupling to construct the hydroquinoline skeleton of symbioimine

Construction of the hydroquinoline skeleton of symbioimine by Cu-mediated N-alkenylation or O-alkenylation of an allyl aminoalcohol, in which either chemoselectivity could lead to the target compound, was investigated. O-alkenylation followed by Claisen rearrangement was favored with high selectivity under a ligand-free condition. Subsequent intramolecular condensation furnished the hydroquinoline skeleton of symbioimine.

Automated summary

The hydroquinoline skeleton of symbioimine was constructed by Cu-mediated N-alkenylation or O-alkenylation of an allyl aminoalcohol. O-alkenylation followed by Claisen rearrangement under ligand-free conditions showed high selectivity, leading to the target compound. Subsequent intramolecular condensation completed the synthesis pathway.