title: Catalytic trimerization of bis-silylated diazomethane.
abstract: (Me(3)Si)(2)CNN isomerizes upon addition of traces of [Me(3)Si](+) ions to give (Me(3)Si)(2)NNC, which then undergoes an unusual trimerization reaction to give exclusively 4-diazenyl-3-hydrazinylpyrazole. As catalyst the isonitrilium ion, [(Me(3)Si)(2)NNC(SiMe(3))](+), was identified and fully characterized. Experiments and computations indicate a three-step reaction including isomerization of diazomethane, a C-C or N-C coupling, and a formal cycloaddition reaction. The kinetics and thermodynamics are discussed on the basis of DFT calculations.
authors.affiliation: Abteilung Anorganische Chemie, Institut für Chemie, Universität Rostock, Albert-Einstein-Straße 3a, D-18059 Rostock, Germany.
authors.forename: Muhammad Farooq
authors.initials: MF
authors.lastname: Ibad
authors.forename: Peter
authors.initials: P
authors.lastname: Langer
authors.forename: Fabian
authors.initials: F
authors.lastname: Reiß
authors.forename: Axel
authors.initials: A
authors.lastname: Schulz
authors.forename: Alexander
authors.initials: A
authors.lastname: Villinger
mesh_terms: D002384:Catalysis; D003500:Cyclization; D003978:Diazomethane / Q000138:chemical synthesis / Q000737:chemistry*; D007700:Kinetics; D015394:Molecular Structure; D011720:Pyrazoles / Q000138:chemical synthesis* / Q000737:chemistry; D011789:Quantum Theory; D013816:Thermodynamics; D014297:Trimethylsilyl Compounds / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D011720:Pyrazoles; D014297:Trimethylsilyl Compounds; D003978:Diazomethane