Zirconium(II)- and Hafnium(II)-Assisted Reductive Coupling of Coordinated Carbonyl Groups Leading to Ketenylidene Complexes of Zirconium(IV) and Hafnium(IV)
✍ Scribed by Prof. Dr. Fausto Calderazzo; Dr. Ulli Englert; Dr. Alessandro Guarini; Dr. Fabio Marchetti; Prof. Dr. Guido Pampaloni; Dr. Annalaura Segre; Dr. Giovanna Tripepi
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 1004 KB
- Volume
- 2
- Category
- Article
- ISSN
- 0947-6539
No coin nor oath required. For personal study only.
✦ Synopsis
The biscyclopentadienyldicar-bony1 derivatives of zirconium(i1) and hafnium(r1) ([MCp,(CO),]; M = Zr, Hf) promote the reductive coupling of coordinated carbon monoxide to give, in the presence of N,N-dialkylcarbamates of the tetravalent metals (M(02CNR2),]. the ketenylidene complexes [M,Cpz(p2-CCO)-(p3-O)(02CNR2)6] (1 a: M = Zr. R = Et; I b : M = Z r . R = i P r ; 2: M = Hf, R = iPr). The yields of the isolated zirconium complexes are as high as 60 YO. while that of the hafnium derivative is 40%. The X-ray crystal structure analysis of 1 b shows that it consists of trinuclear mole-Keywords carbon-carbon coupling * carbonyl complexeshafnium complexes -Z[Ta(OSirBu),] + 2 C 0 --+ ~Ia(O)(OSilBu),] + [Td(CCO)(OSilBu),] (1)