Cyclic Hypervalent Iodine Reagents for Azidation: Safer Reagents and Photoredox-Catalyzed Ring Expansion

Azides are building blocks of increasing importance in synthetic chemistry, chemical biology, and materials science. Azidobenziodoxolone (ABX, Zhdankin reagent) is a valuable azide source, but its safety profile has not been thoroughly established. Herein, we report a safety study of ABX, which shows its hazardous nature. We introduce two derivatives, tBu-ABX and ABZ (azidobenziodazolone), with a better safety profile, and use them in established photoredox- and metal-mediated azidations, and in a new ring-expansion of silylated cyclobutanols to give azidated cyclopentanones

N-Terminal Selective C-H Azidation of Proline-Containing Peptides: a Platform for Late-Stage Diversification

A methodology for the C-H azidation of N-terminal proline-containing peptides was developed employing only commercially available reagents. Peptides bearing a broad range of functionalities and containing up to 6 amino acids were selectively azidated at the carbamate-protected N-terminal residue in presence of the numerous other functional groups present on the molecules. Post-functionalizations of the obtained aminal compounds were achieved: cycloaddition reactions or C-C bond formations via a sequence of imine formation/nucleophilic addition were performed, offering an easy access to diversified peptides.LCS

Cyclic Hypervalent Iodine Reagents for Azidation: Safer Reagents and Photoredox Catalyzed Ring Expansion

Azides are building blocks of increasing importance in synthetic chemistry, chemical biology and materials science. Azidobenziodoxolone (ABX, Zhdankin reagent) is a valuable azide source, but its safety profile has not been thoroughly established. Herein, we report a safety study of ABX, which shows its highly hazardous nature. We further introduce and study two derivatives, tBu-ABX and ABZ (azidobenziodazolone). ABZ displayed a similar reactivity but a better safety profile than ABX, and could be used in established photoredox- and metal-mediated azidation processes, as well as in a new ring-expansion of silylated cyclobutanols to give azidated cyclopentanones

Cyclic Hypervalent Iodine Reagents for Azidation: Safer Reagents and Photoredox Catalyzed Ring Expansion

Azides are building blocks of increasing importance in synthetic chemistry, chemical biology and materials science. Azidobenziodoxolone (ABX, Zhdankin reagent) is a valuable azide source, but its safety profile has not been thoroughly established. Herein, we report a safety study of ABX, which shows its highly hazardous nature. We further introduce and study two derivatives, <i>t</i>Bu-ABX and ABZ (azidobenziodazolone). ABZ displayed a similar reactivity but a better safety profile than ABX, and could be used in established photoredox- and metal-mediated azidation processes, as well as in a new ring-expansion of silylated cyclobutanols to give azidated cyclopentanones