Nitride Formation by Thermolysis of a Kinetically Stable Niobium Dinitrogen Complex
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- 作者：Michael D. Fryzuk ; Christopher M. Kozak ; Michael R. Bowdridge ; Brian O. Patrick ; and Steven J. Rettig
- 刊名：Journal of the American Chemical Society
- 出版年：2002
- 出版时间：July 17, 2002
- 年：2002
- 卷：124
- 期：28
- 页码：8389 - 8397
- 全文大小：145K
- 年卷期：v.124,no.28(July 17, 2002)
- ISSN：1520-5126
文摘
The reduction of [P2N2]NbCl (where [P2N2] = PhP(CH2SiMe2NSiMe2CH2)2PPh) with KC8 undera dinitrogen atmosphere generates the paramagnetic dinuclear dinitrogen complex ([P2N2]Nb)2(
-N2) (2).Complex 2 has been characterized crystallographically and by EPR spectroscopy. Variable-temperaturemagnetic susceptibility measurements indicate that 2 displays antiferromagnetic coupling between twoNb(IV) (d1) centers. A density functional theory calculation on the model complex [(PH3)2(NH2)2Nb]2(-N2)was performed. Thermolysis of ([P2N2]Nb)2(-N2) in toluene generates the paramagnetic bridging nitridespecies where one N atom of the dinitrogen ligand inserts into the macrocycle backbone to form [P2N2]Nb(-N)Nb[PN3] (3) (where [PN3] = PhPMe(CHSiMe2NSiMe2CH2P(Ph)CH2SiMe2NSiMe2N)). Complex 3has been characterized in the solid state as well as by variable-temperature magnetic susceptibilitymeasurements. The reaction of ([P2N2]Nb)2(-N2) with phenylacetylene displaces the dinitrogen fragmentto generate a paramagnetic 
2-alkyne complex, [P2N2]Nb(2-HCCPh) (4).
-N2) (2).Complex 2 has been characterized crystallographically and by EPR spectroscopy. Variable-temperaturemagnetic susceptibility measurements indicate that 2 displays antiferromagnetic coupling between twoNb(IV) (d1) centers. A density functional theory calculation on the model complex [(PH3)2(NH2)2Nb]2(-N2)was performed. Thermolysis of ([P2N2]Nb)2(-N2) in toluene generates the paramagnetic bridging nitridespecies where one N atom of the dinitrogen ligand inserts into the macrocycle backbone to form [P2N2]Nb(-N)Nb[PN3] (3) (where [PN3] = PhPMe(CHSiMe2NSiMe2CH2P(Ph)CH2SiMe2NSiMe2N)). Complex 3has been characterized in the solid state as well as by variable-temperature magnetic susceptibilitymeasurements. The reaction of ([P2N2]Nb)2(-N2) with phenylacetylene displaces the dinitrogen fragmentto generate a paramagnetic 2-alkyne complex, [P2N2]Nb(2-HCCPh) (4).