MEASUREMENTS OF STRUCTURAL AND QUADRUPOLAR COUPLING PARAMETERS FOR 1-CHLOROFERROCENE USING MICROWAVE SPECTROSCOPY
Loading...
Date
1997
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
Rotational spectra for two isotopomers of monochloroferrocene were measured using pulsed beam Fourier transform microwave spectroscopy. This was the first structural study for 1-Chloroferrocene and the first structural study of any substituted ferrocene in the gas phase. Transitions were observed for $^{35}Cl$ and $^{37}Cl$ isotopomers in the 4-10 GHz range. Chlorine quadrupole coupling strengths and rotational constants were obtained from the data. For $^{35}Cl$ the rotational constants and quadrupole coupling strengths are A=1370.009(8) MHz, B=767.342(1) MHz, C=634.8834(6) MHz, $eQq_{aa}=-9.06(4)$ MHz, $eQq_{bb}=-28.43(6)$ MHz, and for $^{37}Cl$, A = 1362.23(2) MHz, B=751.623(2)MHz and C=622.324(1)MHz, $eQq_{aa}=-8.78(17)$ MHz and $eQq_{bb}=^{-}20.79(9)$ MHz. These measured rotational constants were used to determine the following structural parameters of 1-chloroferrocene: $r(Fe-(C_{5}H_{5}) = 1.594(20)$ {\AA}, $r(Fe-(C_{5}H_{4}cl)) = 1,699(13)$ {\AA}, $r(C-Cl) =1,7204(9)$ {\AA} and $r(C-C) = 1,4329(7)$ {\AA}. These results support a trend of increasing $^{5}\eta$-Fe-Cp bond length upon electronegative substitution of the ring. No evidence for internal rotation was observed in the microwave spectrum.
Description
Author Institution: Department of Chemistry, University of Arizona