Metal-free benzannulation of yne-allenone esters for atom-economic synthesis of functionalized 1-naphthols
Hong-Kai Sha,# Feng Liu,# Juan Lu, Zhang-Qin Liu, Wen-Juan Hao,* Jia-Le Tang, Shu-Jiang Tu,* Bo Jiang*
(#共同一作)
A new metal-free benzannulation reaction of yne-allenone esters with H2O by using HOAc as a Lewis acid promoter is reported, providing an atom-economic protocol toward aroyl 1-naphthols with good to excellent yields. Exchanging H2O for aromatic amines resulted in iminated Z-1-naphthols with high stereoselectivity in a highly functional-group-compatible manner under the mild conditions. The purification of these products only needs to be washed by 95% EtOH solvent, thereby avoiding traditional chromatography and recrystallization, which belongs to group-assisted purification (GAP) chemistry.
Green Chem. 2018, 20, 3476-3485