University of Illinois Urbana-Champaign

The Synthesis and Reactions of 2-Diazo-4,5-Bis(trifluoromethyl)imidazole, a Carbene Precursor to Stable Ylide and Hypervalent Compounds

Palmer, Charles Francis, Jr.

This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.

Permalink

https://hdl.handle.net/2142/70378

Description

Title
The Synthesis and Reactions of 2-Diazo-4,5-Bis(trifluoromethyl)imidazole, a Carbene Precursor to Stable Ylide and Hypervalent Compounds
Author(s)
Palmer, Charles Francis, Jr.
Issue Date
1987
Department of Study
Chemistry
Discipline
Chemistry
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Chemistry, Organic
Abstract
  • The synthesis of 2-diazo-4,5-bis(trifluoromethyl)imidazole is discussed. An azo-linkage is used as a masked amine source in a fluorination reaction in which carboxylic acids are converted to trifluoromethyl groups. The azo compound is then hydrogenolyzed to the diazo compound precursor, 2-amino-4,5-bis(trifluoromethyl)imidazole. The diazoimidazole has a diazonium-type structure, with a short N-N bond length of 1.089 A. It may be considered as an ylide of dinitrogen.
  • This stable diazo compound efficiently undergoes either photochemical or thermal decomposition to give an exceptionally electrophilic carbene intermediate which will react with several elements, such as chlorine, bromine, iodine, and sulfur, which contain lone pairs of electrons to produce stable imidazolylides. The syntheses of several stable aryl halonium ylides is described. The X-ray crystal structure for a chloronium ylide prepared from this diazoimidazole is discussed. This ylide has two single bonds to the central chlorine atom with a central bond angle of 105.2$\sp\circ$.
  • Several reactions of the diazo compound are discussed. The diazo compound will also undergo cycloaddition reactions to give new ring systems. The use of the diazoimidazole as a hypervalent ligand is discussed.
Graduation Semester
1987
Type of Resource
text
Permalink
http://hdl.handle.net/2142/70378

Owning Collections

Graduate Dissertations and Theses at Illinois PRIMARY
Graduate Theses and Dissertations at Illinois
Dissertations and Theses - Chemistry