A computational investigation of the role of the iridium dihydrogen pincer complex in the formation of the cyclic pentamer (NH 2BH 2) 5

Kamalika Ghatak, Kumar Vanka

Research output: Contribution to journalArticlepeer-review

12 Scopus citations

Abstract

Computational studies with density functional theory (DFT) and MP2 have been done to investigate the interaction between the iridium dihydrogen pincer complex: (POCOP)IrH 2 (where POCOP=η 3-1,3(OPtBu 2) 2C 6H 3) and NH 2BH 2, the immediate product of ammonia borane (NH 3BH 3) dehydrogenation. A mechanism has been proposed for an oligomerisation process at the metal centre that involves competition between (i) insertion of an NH 2BH 2 molecule into the (NH 2BH 2) n chain and (ii) termination of the chain leading to the formation of the cyclic (NH 2BH 2) n oligomer. The calculated ΔG values show that the competition favours insertion over termination for the cases n=1 to n=4 but favours termination for n=5. The computational studies therefore indicate that the cyclic pentamer (NH 2BH 2) 5 would be formed during NH 3BH 3 dehydrogenation by the (POCOP)IrH 2 catalyst, agreeing with experimental findings. The mechanistic understanding gained has implications for the facile regeneration of ammonia borane.

Original languageEnglish (US)
Pages (from-to)18-29
Number of pages12
JournalComputational and Theoretical Chemistry
Volume992
DOIs
StatePublished - Jul 15 2012
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Condensed Matter Physics
  • Physical and Theoretical Chemistry

Keywords

  • Ammonia borane
  • Hydrogen storage
  • Iridium pincer ligand catalyst
  • Mechanistic studies
  • Oligomerisation cycle

Fingerprint

Dive into the research topics of 'A computational investigation of the role of the iridium dihydrogen pincer complex in the formation of the cyclic pentamer (NH 2BH 2) 5'. Together they form a unique fingerprint.

Cite this