Methyl-to-double bond migration in methylene arenium rhodium complexes

Arkadi Vigalok, David Milstein

Research output: Contribution to journalArticle

23 Citations (Scopus)

Abstract

The novel methylene arenium Rh(I)-Me complexes 5 and 10 were prepared by selective protonation of the corresponding xylylene complexes with HBF4 in cold pentane. These complexes are stable both in the solid state and in solution. Upon reaction with carbon monoxide, the corresponding CO adducts 11 are obtained, which undergo under ambient conditions selective methyl migration to the coordinated double bond of the methylene arenium moiety. This provides an uncommon example of a migratory insertion process in a saturated complex that is promoted by the incoming ligand. No evidence for a concurrent methyl migration to the CO ligand was observed, indicating that the methyl-to-olefin migration is thermodynamically preferred over the carbonylation process. The observed activation entropy (ΔS = -36.1 eu) is in good agreement with an organized transition state for the migration process.

Original languageEnglish
Pages (from-to)2341-2345
Number of pages5
JournalOrganometallics
Volume19
Issue number12
DOIs
Publication statusPublished - Jun 12 2000

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Rhodium
Carbon Monoxide
rhodium
methylene
Ligands
Carbonylation
Protonation
Alkenes
ligands
pentanes
Entropy
Chemical activation
carbon monoxide
adducts
alkenes
insertion
activation
entropy
solid state

ASJC Scopus subject areas

  • Inorganic Chemistry
  • Organic Chemistry

Cite this

Methyl-to-double bond migration in methylene arenium rhodium complexes. / Vigalok, Arkadi; Milstein, David.

In: Organometallics, Vol. 19, No. 12, 12.06.2000, p. 2341-2345.

Research output: Contribution to journalArticle

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