Microwave-Assisted Synthesis and Characterization of Cyclometalated Iridium Complexes
Abstract
Microwave-assisted organic synthesis (MAOS) has gained popularity as a replacement for traditional methods of heating reaction vessels using sand or oil baths and hot plates. MAOS is advantageous due to the use of pressurized vessels that allow for superheating of solvents above their boiling points and the homogeneous distribution of heat within reaction vessels. The application of MAOS and automated column chromatography to the syntheses of cyclometalated iridium chromophores is described in detail for [Ir(pbt)2Cl]2 and [Ir(pbt)2(acac)], where pbt is 2-phenylbenzothiazole and acac is acetylacetonate. The reaction time was reduced to 5 10 of the time required for reported literature procedures by employing MAOS. These results were found to be generally applicable to the general class of [Ir(C^N)2Cl]2 and [Ir(C^N)2(LX)] complexes, where C^N represents a cyclometalating ligand and LX an ancillary ligand. These reduced reaction times result in time and energy savings and allow for high-throughput chemical syntheses when combined with the use of an autosampler. Implementation of automated column chromatography resulted in the rapid, efficient purification of the target chromophores from crude product. Chemical characterization of the materials produced using MAOS demonstrate that the products are identical to those obtained using traditional methods.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 31, 2020
- Accession Number
- AD1108537
Entities
People
- Alexis R. Burnette
- Ryan M O'Donnell
- Thomas Jr N. Rohrabaugh
Organizations
- United States Army Research Laboratory