DETERMINATION OF THE ELECTRONIC PROPERTIES OF CARBORANES, CARBORANE ANIONS AND METALLOCARBORANES FROM 19F NUCLEAR MAGNETIC RESONANCE STUDIES.
Abstract
The preparation of the carbon substituted m- and p- fluorophenyl derivatives of a series of carboranes, carborane anions and metallocarboranes allowed the electronic properties of these species to be determined from 19F nmr chemical shifts and the method of Taft. Species examined in this manner include the 1,2- and 1,7- isomers of the B10C2H12 icosahedral carboranes and the corresponding B9C2H12(-) and B9C2H11(-2) ions as well as the 1,8-B9C2H11 carborane and selected transition metal derivatives of the (3)-1,2- and (3)-1,7-B9C2H11(-2) ions. In several instances large and negative Sigma(R) values were observed which illustrates ground state electron donation from the carborane moiety to the substituted phenyl ring by a pi-mechanism. The Sigma(1) values were affected by both the relative carbon atom positions in the carborane fragments and the presence of a negative charge delocalized in those fragments. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 17, 1970
- Accession Number
- AD0704106
Entities
People
- M. Frederick Hawthorne
- Robert G. Adler
Organizations
- University of California, Riverside