This review describes the characteristic features of simple and nascent N-centered azide radical, and its unique reactivity in fine chemical synthesis with detailed mechanistic discussions.

Cooperative photoredox and palladium catalysis for various functionalization reactions.

The transition metal-free conversion of aryl bromides into aromatic nitriles using an organophotocatalyst under visible light irradiation.

In this paper, we present fluorescent photoremovable protecting groups (FPRPG) based on bis‐acetyl carbazole for the release of two different functional groups such as carboxylic acids, alcohols, thiols, and amines in a sequential fashion. Dual‐arm caged bis‐acetyl carbazoles with different combinations of two unlike functional groups were synthesized. Photophysical studies showed that caged bis‐acetyl carbazoles are blue fluorescent and their emission properties are sensitive to the environment. Sequential photorelease of two different functional groups by bis‐acetyl carbazole was analyzed by HPLC, UV and emission spectroscopy. The mechanism of the dual release by bis‐acetyl carbazole was investigated and supported by TD‐DFT calculations. To demonstrate the applicability of the dual release ability of bis‐acetyl carbazole FPRPG, we synthesized a drug delivery system (DDS) in which one arm of bis‐acetyl carbazole is linked to the carboxylic functional group of chlorambucil (CBL) and the other arm is attached to the hydroxyl group of ferulic acid ethyl ester (FAEE). In vitro studies showed that our DDS presents excellent properties such as photoregulated dual drug delivery, cellular uptake, and biocompatibility.

This report presents the oxygenation of C–H bonds via the merger of photocatalysis and Pd catalysis. Herein, we describe the utilization of a photocatalyst to oxidize an organopalladium­(II) intermediate to high-valent PdIII or PdIV intermediates, which promotes the formation of C–O bonds. The demonstrated method works efficiently with various directing groups, such as oxime ether and benzothiazole. The applicability of this direct C–O bond formation method is shown by synthesizing several metal complexes of 2-(benzo­[d]­thiazol-2-yl)­phenol that can be used in organic light-emitting diodes and pharmaceuticals.