Yoshitomo Nagasawa

Metal-free synthesis of imidazopyridine from nitroalkene and 2-aminopyridine in the presence of a catalytic amount of iodine and aqueous hydrogen peroxide

We have developed a metal-free synthetic method for 3-nitroimidazo[1,2-a]pyridines from nitroalkenes and 2-aminopyridines using catalytic amounts of iodine and aqueous hydrogen peroxide as a terminal oxidant.

Intermolecular Cyclopropanation of Styrenes Using Iodine and Visible Light via Carbon–Iodine Bond Cleavage

The intermolecular cyclopropanation of aromatic olefins with activated methylene compounds using iodine and visible light irradiation was described. This reaction proceeds under rare-metal-free conditions. Styrenes with various substituted groups (alkyl and electron-withdrawing groups) provided corresponding cyclopropanes in moderate to good yields.

Synthesis of benzoyl cyanide through aerobic photooxidation of benzyl cyanide using carbon tetrabromide as a catalyst

We developed a synthetic method toward benzoyl cyanide through aerobic photooxidation of benzyl cyanide in the presence of carbon tetrabromide under visible light irradiation with fluorescent lamps.

Aerobic photooxidative synthesis of 2-aryl-4-quinazolinones from aromatic aldehydes and aminobenzamide using catalytic amounts of molecular iodine

This study reports a safe, mild, and environmentally benign synthetic method toward 2-aryl-4-quinazolinones from aromatic aldehydes and aminobenzamides through a cyclization–oxidation sequence using a catalytic amount of iodine, which serves as both a Lewis acid and an oxidant, harmless visible light irradiation, and molecular oxygen as the terminal oxidant.

Aerobic Photooxidative Synthesis of β-Alkoxy Monohydroperoxides Using an Organo Photoredox Catalyst Controlled by a Base

Transition-metal-free synthesis of β-alkoxy monohydroperoxides via aerobic photooxidation using an acridinium photocatalyst was developed. This method enables the synthesis of some novel hydroperoxides. The peroxide source is molecular oxygen, which is cost-effective and atomically efficient. Magnesium oxide plays an important role as a base in the catalytic system.

Synthesis of 2-hydroxymalonic acid derivatives via tandem oxidation and rearrangement by photo organic catalysis

This report describes a mild method for the direct transformation of β-oxoesters to the corresponding 2-hydroxymalonic esters, tartronic esters, using singlet oxygen produced by a catalytic amount of methylene blue and visible light irradiation using fluorescent lamps. In addition, β-oxoamides were also converted to the corresponding 2-hydroxymalonic ester amides.