Rapid-injection NMR study of iodo- and cyano-Gilman reagents with 2-cyclohexenone: observation of pi-complexes and their rates of formation.
Rapid-injection is a very useful technique for the preparation of temperature-sensitive and air-sensitive compounds in the cold, nitrogen-filled probe of an NMR spectrometer. We have used this method to prepare solutions of pi-complexes from 2-cyclohexenone and prototypical cuprates Me2CuLi.LiI and Me2CuLi.LiCN, and we have assigned structures on the basis of 1H and 13C NMR. In each case two pi-complexes were observed, and in the former, their rates of formation were measured by rapid-injection 1H NMR and EXSY spectroscopy. These results provide insights into the normal and anomalous conjugate addition reactions of organocuprates.
Bertz
Steven H
SH
Department of Chemistry, University of North Carolina-Charlotte, UNCC Station, Charlotte, North Carolina 28223, USA. cogle@email.uncc.edu
Carlin
Clifford M
CM
Deadwyler
Daniel A
DA
Murphy
Michael D
MD
Ogle
Craig A
CA
Seagle
Paul H
PH