Decatungstate-photocatalysed C(sp³)-H azidation

C-H Azidation is an increasingly important tool for bioconjugation, materials chemistry, and the synthesis of nitrogen-containing natural products. While several approaches have been developed, these often require exotic and energetic reagents, expensive photocatalysts, or both. Here we report a simple and general C-H azidation reaction using earth-abundant tetra-n-butylammonium decatungstate as a photocatalyst and commercial p-acetamidobenzenesulfonyl azide (p-ABSA) as the azide source. This system can azidate a variety of unactivated C(sp³)-H bonds in moderate to good yields and excellent turnover numbers. Preliminary mechanistic experiments implicate a radical mechanism proceeding VIA photo-hydrogen atom transfer (photo-HAT).