A one-pot synthesis of thieno[2,3-b]indoles is reported via a Lawesson's reagent-mediated thiocarbonyl Cloke–Wilson rearrangement of spiro donor–acceptor cyclopropyl oxindoles, followed by oxidative aromatization under open–air conditions.
A copper-catalyzed Cloke–Wilson rearrangement using 1,1,2,2-tetrasubstituted cyclopropanes has been developed. Yielding a myriad of dihydrofuran derivatives with tetrasubstituted carbon centers, which widely exist in bioactive compounds.
All different tetraaryl furans tolerating cross-coupling-reactive aryl halides were readily synthesised by oxidative aromatization of the corresponding tetraaryl dihydrofuran esters from annulative Cloke–Wilson rearrangement.
In the present study, the mechanism, origin of chemoselectivity, and substituent effects of the phosphine-catalyzed ring-opening reaction of cyclopropyl ketone have been investigated using the DFT method.
Small molecules, such as trimethylamine N-oxide, interrupt intramolecular photoreactions of quinones by proton transfer and allow to convert a variety of quinones to spirocyclopropanes in a catalytic, diastereoselective, and atom-conserving manner.