Construction of pyrroles, furans and thiophenes via intramolecular cascade desulfonylative/dehydrogenative cyclization of vinylidenecyclopropanes induced by NXS (X = I or Br)

Abstract

Pyrroles, furans, and thiophenes are important structural motifs in biologically active substances, pharmaceuticals and functional materials. In this paper, we disclosed an efficient synthetic strategy for the rapid construction of...

Iodine radical mediated cascade [3 + 2] carbocyclization of ene-vinylidenecyclopropanes with thiols and selenols via photoredox catalysis

“…6 As an eco-friendly and cost-effective accelerator, iodine and its derivatives present undisputed advantages in most cases, including being easily operated and metal-free, as well as affording economies of resource, time, and labor. It is well known that the coordination between the electrophilic iodine cation and the unsaturated bond can generate the corresponding iodinium ion, 7 which would be subsequently attacked by other unsaturated groups within the molecule, triggering a cascade cyclization reaction to obtain the iodocyclization products (Scheme 1b). 7 For example, our group reported a novel cascade process for the synthesis of 3,3′-diphenyl-1,1′-spirobi[indene] derivatives from propargyl alcohol-tethered alkylidenecyclopropanes in the presence of I 2 .…”

“…It is well known that the coordination between the electrophilic iodine cation and the unsaturated bond can generate the corresponding iodinium ion, 7 which would be subsequently attacked by other unsaturated groups within the molecule, triggering a cascade cyclization reaction to obtain the iodocyclization products (Scheme 1b). 7 For example, our group reported a novel cascade process for the synthesis of 3,3′-diphenyl-1,1′-spirobi[indene] derivatives from propargyl alcohol-tethered alkylidenecyclopropanes in the presence of I 2 . 7 e In addition, Liang's group presented iodine promoted cascade cycloisomerization of 1-en-6,11-diynes for the easy preparation of tetrahydrobenzo[ f ]isoquinolines.…”