Electronic Control of the Asymmetry in Heteroatom Monosubstituted Olefin Bonding to the Cyclopentadienyl Iron(II) Dicarbonyl Cation. A Hammett Correlation Study
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- 作者：Stephen A. Matchett ; Brenda R. Schmiege-Boyle ; John Cooper ; David Fratterelli ; Kirk Olson ; Justin Roberts ; James Thommen ; Dean Tigelaar ; and Frederique Winkler
- 刊名：Organometallics
- 出版年：2003
- 出版时间：November 24, 2003
- 年：2003
- 卷：22
- 期：24
- 页码：5047 - 5053
- 全文大小：118K
- 年卷期：v.22,no.24(November 24, 2003)
- ISSN：1520-6041
文摘
Nucleophilic substitution of CpFe(CO)2(
fchars/eta.gif" BORDER=0 >2-H2CC(H)OEt)+PF6- with para-substitutedanilines was used to prepare a series (4-10) of fchars/eta.gif" BORDER=0 >2-vinyl aniline Fp+ complexes of the generalformula CpFe(CO)2[fchars/eta.gif" BORDER=0 >2-CH2C(H)NH(p-C6H4X)]+PF6-, where X = OMe (4), Me (5), H, (6), Br(7), COMe (8), CN (9), and NO2 (10). Correlation of the Hammett fchars/sigma.gif" BORDER=0 > para parameters withthe 13C NMR shifts of the metal-coordinated vinyl carbons demonstrated the ability to controlthe position of the Fp+ moiety along the olefin face. As the electron-donating character ofthe para substituent was increased, the Fp+ moiety was displaced away from the nitrogen-bearing carbon, increasing the asymmetry of the metal-olefin bonding. These conclusionswere further supported by determining the X-ray crystal structure of the p-Me (5) and thep-acetyl (8) derivatives.
fchars/eta.gif" BORDER=0 >2-H2CC(H)OEt)+PF6- with para-substitutedanilines was used to prepare a series (4-10) of fchars/eta.gif" BORDER=0 >2-vinyl aniline Fp+ complexes of the generalformula CpFe(CO)2[fchars/eta.gif" BORDER=0 >2-CH2C(H)NH(p-C6H4X)]+PF6-, where X = OMe (4), Me (5), H, (6), Br(7), COMe (8), CN (9), and NO2 (10). Correlation of the Hammett fchars/sigma.gif" BORDER=0 > para parameters withthe 13C NMR shifts of the metal-coordinated vinyl carbons demonstrated the ability to controlthe position of the Fp+ moiety along the olefin face. As the electron-donating character ofthe para substituent was increased, the Fp+ moiety was displaced away from the nitrogen-bearing carbon, increasing the asymmetry of the metal-olefin bonding. These conclusionswere further supported by determining the X-ray crystal structure of the p-Me (5) and thep-acetyl (8) derivatives.