Photochemical synthesis of benzoxazolo[3,2-b]isoquinolin-11-one and isoquinolino[3,2-b][1,3]benzoxazin-11-one under basic conditions

Integrating C-H activation/2-fold annulation: a modular access to heteroaryl-tethered oxazoloisoquinolinones

A cascade C-H activation/2-fold annulation of 2-aryloxazolines with pyridotriazoles has been achieved employing Rh-catalysis to afford heteroaryl-tethered oxazoloisoquinolinones. The synergistic annulations, functional group tolerance, and late-stage skeletal editing of the bioactive scaffolds are the salient practical features.

Superelectrophiles in Synthesis: Preparation of Aromatic Imides

Aromatic carboxylic acids are found to undergo reactions with isocyanates, wherein triflic acid promotes the formation of aromatic imide products in fair to good yields. It is proposed that the carboxylic acid group directs the isocyanate electrophile to the ortho-position. This is thought to occur by the formation of a temporary carbamic acid anhydride group, which cleaves upon ortho-functionalization. A series of imide products are synthesized, and the synthesis of a potential selective inhibitor of tyrosyl DNA phosphodiesterase II is performed.

Photochemical and photophysical behavior of indolyl anions in photostimulated intramolecular arylation reactions

O-Arylation reaction is obtained when N-(2-halophenyl) indolo carboxamides are irradiated in a basic medium. On the basis of photochemical and photophysical experiments, we propose that 2-indolylbenzoxazole is formed by intramolecular electron transfer followed by fast dehalogenation of the halophenyl radical anion pendant moiety, finally a radical-radical collapse renders the observed product.