Phthalazinone-Assisted C-H Amidation Using Dioxazolones Under Rh(III) Catalysis.

The preparation of phthalazinone derivatives is pivotal for their utilization as pharmaceutical agents and other entities. Herein, we report the phthalazinone-assisted carbon-nitrogen bond forming reaction using dioxazolones as robust amidation sources under Rh(III) catalysis. The broad functional group tolerance and complete site-selectivity are observed. Notably, a series of transformations of synthesized compounds into biologically relevant N-heterocycles demonstrates the applicability of the developed methodology.

Ru(II)-Catalyzed C-H Hydroxyalkylation and Mitsunobu Cyclization of N-Aryl Phthalazinones.

Ruthenium(II)-catalyzed C(sp2)-H functionalization of N-aryl phthalazinones with a range of aldehydes and activated ketone is described. Initial formation of hydroxyalkylated phthalazinones and subsequent Mitsunobu cyclization provided facile access to biologically relevant indazolophthalazinones. The utility of this method is highlighted by synthetic transformations into a series of potentially bioactive scaffolds.