Electronic halocyclization and radical haloazidation of benzene-linked 1,7-dienes for the synthesis of functionalized 3,1-benzoxazines.

A novel electronic halocyclization and radical haloazidation of benzene-linked 1,7-dienes for the formation of functionalized 3,1-benzoxazines has been achieved by using TMSN3 as an azido source and NBS as a halogen source. This methodology is highlighted by its mild conditions and wide substrate scope, which concomitantly introduces one C-N and two C-halogen bonds into one molecule.

Visible-Light-Induced Trifluoromethylation of Isonitrile-Substituted Methylenecyclopropanes: Facile Access to 6-(Trifluoromethyl)-7,8-Dihydrobenzo[k]phenanthridine Derivatives.

A new visible-light-induced trifluoromethylation of isonitrile-substituted methylenecyclopropanes is developed. A range of substituted 6-(trifluoromethyl)-7,8-dihydrobenzo[k]phenanthridine derivatives are readily furnished by this newly developed tandem reaction with moderate to good yields. This reaction allows the direct formation of two six-membered rings and three new C-C bonds, including the C-CF3 bond, under visible light irradiation.

Palladium-catalyzed cascade cyclization of allylamine-tethered alkylidenecyclopropanes: facile access to iodine/difluoromethylene- and perfluoroalkyl-containing 1-benzazepine scaffolds.

The unprecedented palladium-catalyzed cascade cyclization of allylamine-tethered alkylidenecyclopropanes with an ethyl difluoroiodoacetate or perfluoroalkylated reagent is developed, providing facile access to a variety of synthetically and medicinally valuable iodine/difluoromethylene- and perfluoroalkyl-containing 1-benzazepine frameworks. These reactions exhibited good yields and functional group tolerance via a radical mechanism.

Thermally induced formal [3+2] cyclization of ortho-aminoaryl-tethered alkylidenecyclopropanes: facile synthesis of furoquinoline and thienoquinoline derivatives.

We have developed a facile synthetic method to access furoquinoline and thienoquinoline derivatives via a thermally induced ring-opening and cyclization reaction from ortho-aminoaryl-tethered alkylidenecyclopropanes with the in situ generation of isocyanates or isothiocyanates. These reactions exhibited excellent yields and functional group tolerance under metal-free conditions.