posted on 2024-02-28, 17:08authored byKoutarou Amano, Tomoko Kawasaki-Takasuka, Keiji Mori
A synthetic
strategy for forming multisubstituted naphthalenes
based on hydride shift mediated C(sp3)–H bond functionalization
was developed. This strategy consists of three successive transformations:
(1) an intramolecular hydride shift mediated C(sp3)–H
bond functionalization; (2) a decarboxylative fragmentation; and (3)
an oxidation reaction. When benzylidene malonates having a 2-alkoxyethyl
group at the ortho position were treated with a catalytic
amount of Al(OTf)3, the hydride shift/cyclization reaction
proceeded smoothly to afford tetralin derivatives in good chemical
yields. The resulting tetralins were easily converted into naphthalenes
by exposing them to modified Krapcho decarboxylation reaction conditions
(LiCl, DMSO, and heating under an O2 atmosphere). The one-pot
operation of these two reactions was also realized.