Thermal decomposition of [Me3SiNCH2CH2NSiMe3] · Li2(THF)2 to [LiN(SiMe3)2 · THF]2 via a 1,4-trimethylsilyl shift

Helmut Mack, Gerlinde Frenzen, Michael Bendikov, Moris S. Eisen

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

The dilithium salt [Me3SiNCH2CH2NSiMe3] · Li2(THF)2 decomposes slowly upon heating forming a metastable structure of the crystalline [LiN(SiMe3) · THF]2. The crystal structure of the new form was established by single crystal X-ray diffraction showing a decrease in the a and b parameter values of the unit cell, and an expansion of the c value as compared with the structure obtained at room temperature. The major discrepancies among the known and the metastable crystalline framework are the Li-O bond length and the dihedral angle disposition of the trimethylsilyl groups as regarded to the middle Li-N-Li-N heterocyclobutane ring. Attempts to trap the expected additional lithium imine product were unsuccessful although quenching experiments produced polyethyleneimine.

Original languageEnglish
Pages (from-to)39-43
Number of pages5
JournalJournal of Organometallic Chemistry
Volume549
Issue number1-2
Publication statusPublished - Dec 18 1997

Fingerprint

Polyethyleneimine
Imines
Lithium
X-Ray Diffraction
Heating
imines
thermal decomposition
dihedral angle
Pyrolysis
Salts
lithium
Hot Temperature
quenching
traps
Crystalline materials
salts
crystal structure
Temperature
heating
expansion

Keywords

  • Lithium amide
  • Polyethyleneimine
  • TMS-shift
  • X-ray crystal structure

ASJC Scopus subject areas

  • Biochemistry
  • Inorganic Chemistry
  • Organic Chemistry
  • Physical and Theoretical Chemistry
  • Materials Chemistry

Cite this

Thermal decomposition of [Me3SiNCH2CH2NSiMe3] · Li2(THF)2 to [LiN(SiMe3)2 · THF]2 via a 1,4-trimethylsilyl shift. / Mack, Helmut; Frenzen, Gerlinde; Bendikov, Michael; Eisen, Moris S.

In: Journal of Organometallic Chemistry, Vol. 549, No. 1-2, 18.12.1997, p. 39-43.

Research output: Contribution to journalArticle

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AB - The dilithium salt [Me3SiNCH2CH2NSiMe3] · Li2(THF)2 decomposes slowly upon heating forming a metastable structure of the crystalline [LiN(SiMe3) · THF]2. The crystal structure of the new form was established by single crystal X-ray diffraction showing a decrease in the a and b parameter values of the unit cell, and an expansion of the c value as compared with the structure obtained at room temperature. The major discrepancies among the known and the metastable crystalline framework are the Li-O bond length and the dihedral angle disposition of the trimethylsilyl groups as regarded to the middle Li-N-Li-N heterocyclobutane ring. Attempts to trap the expected additional lithium imine product were unsuccessful although quenching experiments produced polyethyleneimine.

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