Redox reactions of low-valent group 4 organometallics with 9,10-phenanthrenequinone (PQ). Crystal and molecular structure of a 10-membered tetraoxametallacycle of bis(cyclopentadienyl)zirconium(IV)

• Published in: Journal of organometallic chemistry 1997-09, Vol.543 (1), p.201-207
• Main Authors: Calderazzo, F., Englert, U., Pampaloni, G., Kölle, U., Tripepi, G.
• Format: Article
• Language: English
• ISSN: 0022-328X; 1872-8561
• DOI: 10.1016/S0022-328X(97)00159-9

The bis(arene) derivative of titanium(O), Ti(η 6-toluene) 2, reacts with 9,10-phenanthrenequinone (PQ) with release of the arene ligands and formation of a diamagnetic brown compound best formulated as a dinuclear titanium(IV) derivative containing both 9,10-phenanthrenesemiquinone (PSQ) and 9,10-phenanthrenediolato (PDA) ligands. MCp 2(CO) 2 (M = Zr, Hf) react with PQ to give MCp 2PDA which has been characterized by single crystal X-ray diffractometry for M = Zr. Crystal data: C 48H 36O 4Zr 2, M = 859.26gmol −1, monoclinic, space group P2 1/ n (No. 14), a = 11.647(8), b = 17.07(1), c = 18.80(1) Å, β = 97.17(6)°, V = 3709(7)Å 3, Z = 4, d calc = 1.539g cm −3, μ = 5.97cm −1, F(000) = 1744. The structure consists of dinuclear [ZrCp 2PDA] 2 units, the two ZrCp 2 groups being bridged by the PDA ligands to give a 10-membered tetraoxazirconacycle.