Surprisingly great difference in reactivity depending upon the ring size: Solvolysis and molecular structure study of some N-trimethylsilylated cyclic ureas

Roland Szalay, Gábor Pongor, V. Harmat, Zsolt Böcskei, Dezso Knausz

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

The molecular structure of N-trimethylsilylated five- (1a-c), six- (2a,b) and seven-membered (3) cyclic ureas was studied by single crystal X-ray diffraction method and quantum chemical calculations. Solvolysis rate constants of compounds in n-octanol/tetrahydrofuran mixtures were determined by gas chromatography. An alternative sampling method eliminating the effect of the hot injector was also developed in the rate measurement of 2a. The half-lives of the five-membered rings (1a,b) were found to be at least three orders of magnitude higher than those of the six- (2a,b) and seven- (3) membered ones. Relationship between the reactivity and the extent of the pseudo- pentacoordination around the silicon centre in reactants was found. The results are in correlation to our simple static (structure-based) predictive model established previously.

Original languageEnglish
Pages (from-to)1498-1506
Number of pages9
JournalJournal of Organometallic Chemistry
Volume690
Issue number6
DOIs
Publication statusPublished - Mar 15 2005

Fingerprint

1-Octanol
solvolysis
Silicon
Molecular Structure
ureas
Urea
Gas chromatography
Molecular structure
Rate constants
molecular structure
reactivity
Single crystals
Sampling
X ray diffraction
rings
gas chromatography
tetrahydrofuran
injectors
X-Ray Diffraction
half life

Keywords

  • Pseudo-pentacoordination
  • Reactivity
  • Silyl
  • Solvolysis
  • Urea

ASJC Scopus subject areas

  • Chemical Engineering (miscellaneous)
  • Materials Science (miscellaneous)
  • Materials Chemistry
  • Physical and Theoretical Chemistry
  • Organic Chemistry
  • Inorganic Chemistry
  • Biochemistry

Cite this

Surprisingly great difference in reactivity depending upon the ring size : Solvolysis and molecular structure study of some N-trimethylsilylated cyclic ureas. / Szalay, Roland; Pongor, Gábor; Harmat, V.; Böcskei, Zsolt; Knausz, Dezso.

In: Journal of Organometallic Chemistry, Vol. 690, No. 6, 15.03.2005, p. 1498-1506.

Research output: Contribution to journalArticle

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