Polymer Skeletal Editing via Anionic Brook Rearrangements.

This report communicates the first example of polymer backbone metamorphosis affected by anionic 1,2-Brook rearrangement of acyl silane moieties. Introduction of the acyl silane functionality into a polymer backbone was achieved via acyclic diene metathesis copolymerization (ADMET) of diene and two dienes. We demonstrate that, using organolithium species and cyanide as nucleophiles, the backbones of resulting copolymers can be triggered to undergo highly efficient 1,2-Brook rearrangement, which transforms the poly(acyl silane)s into poly(silyl ether)s.

Visible-Light-Induced Palladium-Catalyzed Generation of Aryl Radicals from Aryl Triflates.

A mild visible-light-induced Pd-catalyzed intramolecular C-H arylation of amides is reported. The method operates by cleavage of a C(sp )-O bond, leading to hybrid aryl Pd-radical intermediates. The following 1,5-hydrogen atom translocation, intramolecular cyclization, and rearomatization steps lead to valuable oxindole and isoindoline-1-one motifs.

A mild light-induced cleavage of the S-O bond of aryl sulfonate esters enables efficient sulfonylation of vinylarenes.

A new mode of S-O bond activation has been discovered, which constitutes novel reactivity of easily available and bench-stable arylsulfonate phenol esters. This protocol enables access to putative sulfonyl radical intermediates, which enable straightforward access to valuable vinyl sulfones.

Palladium-Catalyzed Atom-Transfer Radical Cyclization at Remote Unactivated C(sp )-H Sites: Hydrogen-Atom Transfer of Hybrid Vinyl Palladium Radical Intermediates.

A novel mild, visible-light-induced palladium-catalyzed hydrogen atom translocation/atom-transfer radical cyclization (HAT/ATRC) cascade has been developed. This protocol involves a 1,5-HAT process of previously unknown hybrid vinyl palladium radical intermediates, thus leading to iodomethyl carbo- and heterocyclic structures.

Au-Catalyzed Pentannulation Reaction of Propargylic Esters Occurring at C(sp(3))-H Site.

A gold-catalyzed cascade cyclization reaction of easily accessible propargylic esters to cyclopentenones has been developed. This transformation features an unprecedented pentannulation reaction of propargylic esters which occurs at an unactivated C(sp(3))-H site to efficiently produce functionalized mono-, bis-, and tricyclic cyclopentenones.