Synthesis Of 2-aminobenzoxazoles Research Articles

Utilization of 2-nitrophenols in annulations with aryl isothiocyanates towards the synthesis of 2-aminobenzoxazoles.

A method for the annulation of 2-nitrophenols with aryl isothiocyanates is reported. The reactions proceeded in the presence of an iron(iii) acetylacetonate catalyst, elemental sulfur, NaOH as a base, and DMSO as a solvent. Derivatives of 2-aminobenzoxazoles bearing nitro, cyano, acetyl, sulfone, secondary amine, and pyrrolyl groups were successfully isolated.

The Synthesis of 2-Aminobenzoxazoles Using Reusable Ionic Liquid as a Green Catalyst under Mild Conditions.

A facile, green, and efficient method for the direct oxidative amination of benzoxazoles using heterocyclic ionic liquid as catalyst has been developed. The reaction proceeded smoothly at room temperature and gave the desirable 2-aminobenzoxazoles with good to excellent yields (up to 97%). The catalyst 1-butylpyridinium iodide can be easily recycled and reused with similar efficacies for at least four cycles.

ChemInform Abstract: Amination of Benzoxazoles by Visible‐Light Photoredox Catalysis.

AbstractPrimary amines or anilines are not applicable to the developed conditions.

N-Bromosuccinimide as an oxidant for the transition-metal-free synthesis of 2-aminobenzoxazoles from benzoxazoles and secondary amines

A facile and transition-metal-free method was developed through merging the ring opening of benzoxazoles with secondary amines and N-bromosuccinimide (NBS) mediated oxidative cyclization toward the synthesis of 2-aminobenzoxazoles. NBS was selected as a powerful oxidant in the oxidative cyclization of ring-opening amidines to provide the desirable 2-aminobenzoxazoles in excellent yields (up to 94%).

Synthesis of 2-aminobenzoxazoles via copper-catalyzed electrophilic amination of benzoxazoles with O-benzoyl hydroxylamines

An efficient copper-catalyzed electrophilic amination of benzoxazoles with O-benzoyl hydroxylamines is described, employing CuCl catalyst, PPh3 ligand, and LiOtBu base. This simple air-stable copper catalysis enables the preparation of various 2-aminobenzoxazole derivatives at room temperature in good yields.

A method for the synthesis of 2-aminobenzoxazoles

A synthesis of 2-aminobenzoxazoles from the parent C–H compound is described. The procedure involves deprotonation at the 2-position of the benzoxazole and quenching the intermediate organolithium species with a halogen electrophile. The 2-halobenzoxazole is then treated in the same pot with an amine nucleophile to afford the desired product. The substrate scope and selectivity of the reaction are presented. The method is operationally simple and provides access to a variety of amine products bearing additional nucleophilic heteroatoms.

Highly Efficient One-Pot Synthesis of 2-Aminobenzoxazoles Using Triflic Acid as a Cyclodesulfurizing Reagent

An efficient one-pot synthetic strategy for 2-aminobenzoxazoles was developed from isothiocyanates and 2-aminophenol using triflic acid as a cyclodesulfurizing reagent.

Synthesis of 2-Aminobenzoxazoles from 2-Aminophenols

Synthesis of 2-Aminobenzoxazoles from 2-Aminophenols

Synthesis of 2-Aminobenzoxazoles Using Tetramethyl Orthocarbonate or 1,1-Dichlorodiphenoxymethane

The synthesis of 2-aminobenzoxazoles can be readily achieved by two versatile, one-pot procedures utilizing commercially available tetramethyl orthocarbonate or 1,1-dichlorodiphenoxymethane, an amine, and an optionally substituted 2-aminophenol. The reactions were conducted under mild conditions and provided 2-aminobenzoxazoles in modest to excellent yields. A variety of amines and substituted 2-aminophenols were used to investigate the scope of the reactions.