Electronic structure of 7-membered zirconacyclocumulenes by Vibrational spectra and QTAIM
Journal of Molecular Structure(2021)
Abstract
The vibrational spectra (IR and Raman) for seven-membered zirconacyclocumulenes of the type Cp2Zr[eta(3)-(RC)-C-1=C=C=C(R-1)-C(R-3)=CR2], R-1 = SiMe3, Bu-t, R-2 ,R-3 =Ph, SiMe3, Bu-t, -C C-SiMe3 -C C-Bu-t] were ob tained and studied using normal coordinate analysis. For metallacycles of this type, three lines are pronounced: 1870 and 1650 cm(-1) bands corresponding to symmetric (nu(1)) and antisymmetric (nu(2)) vibrations of cumulene fragment, as well as at similar to 1400 cm(-1) the nu C=C vibration, respectively. These data are consistent with the geometric parameters of the cycles and the results of QTAIM analysis, within which the molecular graph demonstrated three Zr-C bond paths. For a crystalline sample of the Cp2Zr[eta(3)-Me3SiC4(SiMe3)-C(Ph)=CPh] complex (2Zr(e)), irreversible isomerization under the action of a He-Ne laser into the cyclopentadiene structure Cp2Zr[eta(2)-(Me3SiC C)C=C(SiMe3)-C(Ph)=CPh] with a pendant alkyne substituent. Based on the IR spectra data for the Cp2Zr[eta(3)-Me3SiC4(SiMe3)-C(SiMe3)=C--C C-SiMe3] (2Zr(d)) complex, the preservation of the cyclocumulene structure in the dynamic process of its isomerization was proved. (C) 2021 Elsevier B.V. All rights reserved.
MoreTranslated text
Key words
Zirconacyclocumulene,electronic structure,QTAIM,Raman,isomerization
AI Read Science
Must-Reading Tree
Example
![](https://originalfileserver.aminer.cn/sys/aminer/pubs/mrt_preview.jpeg)
Generate MRT to find the research sequence of this paper
Chat Paper
Summary is being generated by the instructions you defined