Reaction of trans-[Cr(CO)(3)(mu,eta:eta-indenyl)Rh(CO)(2)] at room temperature in CH2Cl2 with norbornadiene (NBD) yields trans-[Cr(CO)(3)(mu,eta:eta-indenyl)Rh(NBD)], 3. X-ray analysis for 3 shows a = 8.200(5) Angstrom, b = 11.388(5) Angstrom, c = 17.868 Angstrom,beta = 92.1 degrees, space group P2(1)/c. In contrast with the cis-[Cr(CO)(3)(mu,eta:eta-indenyl)Rh(NBD)], 2, isomer, the indenyl moiety in 3 is far less distorted, and the planes defined by [C-1, C-2, C-3] of the indenyl frame and by [C-11, C-12, C-14, C-15] of NBD are almost exactly parallel to each other, showing an undistorted coordination about the rhodium atom. Under suitable conditions (THF as solvent in the presence of the tetrafluoroborate salt of [Rh(NBD)](+), or a similar cation species) 3 undergoes a fast intramolecular rearrangement to give the isomer cis-[Cr(CO)(3)(mu,eta:eta-indenyl)Rh(NBD)], 2. The process exhibits a relatively low activation enthalpy (Delta H-double dagger = 11.7 +/- 0.9 kcal mol(-1)) and a very negative activation entropy (Delta S double dagger = -30 +/- 3 cal mol(-1) K-1).

HETEROBIMETALLIC INDENYL COMPLEXES - THE TRANS-CIS ISOMERIZATION OF CR(CO)(3)(MU,ETA-ETA-INDENYL)RH(NBD

CECCON, ALBERTO;SANTI, SAVERIO;
1995

Abstract

Reaction of trans-[Cr(CO)(3)(mu,eta:eta-indenyl)Rh(CO)(2)] at room temperature in CH2Cl2 with norbornadiene (NBD) yields trans-[Cr(CO)(3)(mu,eta:eta-indenyl)Rh(NBD)], 3. X-ray analysis for 3 shows a = 8.200(5) Angstrom, b = 11.388(5) Angstrom, c = 17.868 Angstrom,beta = 92.1 degrees, space group P2(1)/c. In contrast with the cis-[Cr(CO)(3)(mu,eta:eta-indenyl)Rh(NBD)], 2, isomer, the indenyl moiety in 3 is far less distorted, and the planes defined by [C-1, C-2, C-3] of the indenyl frame and by [C-11, C-12, C-14, C-15] of NBD are almost exactly parallel to each other, showing an undistorted coordination about the rhodium atom. Under suitable conditions (THF as solvent in the presence of the tetrafluoroborate salt of [Rh(NBD)](+), or a similar cation species) 3 undergoes a fast intramolecular rearrangement to give the isomer cis-[Cr(CO)(3)(mu,eta:eta-indenyl)Rh(NBD)], 2. The process exhibits a relatively low activation enthalpy (Delta H-double dagger = 11.7 +/- 0.9 kcal mol(-1)) and a very negative activation entropy (Delta S double dagger = -30 +/- 3 cal mol(-1) K-1).
1995
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11577/2505534
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 28
  • ???jsp.display-item.citation.isi??? 27
  • OpenAlex ND
social impact