An open chain trinuclear titanium(IV) isopropoxide species formed with the tridentate ligand cis,cis–cyclohexane–1,3,5-trialkoxide [C6H9O3]3−. Crystal structure of [{Ti(OPri)3}2{μ-Ti(C6H9O3-O1,O5)2}]

Multiple bridging modes in a novel trinuclear titanium 1,3-dioxypropane compound, Ti3(methyliminodiethanolate)2(1,3-propanediolate)4

“…Two of these ligands provide the edge-sharing of the distorted octahedra. As observed previously (Corden et al, 1999;Boyle et al, 1997), these TiÐO bonds are much longer than normal non-bridged TiÐO bonds, varying, in (I), from 1.988 (2) to 2.082 (2) A Ê , with mean values for TiÐOÐC, TiÁ Á ÁTi and TiÐ O of 123.6 , 3.322 (1) A Ê and 2.04 A Ê , respectively. These values are at the upper end of the spectrum of published values; in a subset of titanium six-coordinate oxo complexes, where one Ti…”

Synthesis of di-, tri- and penta-nuclear titanium(iv) species from reactions of titanium(iv) alkoxides with 2,2′-biphenol (H2L1) and 1,1′-binaphthol (H2L2); crystal structures of [Ti3(μ2-OPri)2(OPri)8L1], [Ti3(OPri)6L13], [Ti5(μ3-O)2(μ2-OR)2(OR)6L

“…In the related derivative 1, the six terminal OPr i groups do exhibit fluxional behaviour, although the groups in 1 are in a different arrangement compared to those in 2. 14 Subsequent experiments showed that under the above conditions the reaction does not proceed beyond the mono-substitution stage {i.e. empirically [Ti(OPr i ) 2 L 1 ]} because the same product 2 was obtained even when the molar ratio of reactants (Ti : ligand) was varied over the range 2 : 1, 1 : 1 and 1 : 2.…”

“…The central titanium is in an approximately octahedral environment, whilst the other two occupy five co-ordinate sites with  values close to 0.3 (0.29 and 0.33), where a  value of 0.3 implies that the co-ordinate geometry is 30% along the pathway of distortion from square pyramidal towards trigonal bipyramidal. 24 As in the structure of 1 14 the Ti-O (bridge) distances different trinuclear species [Ti 3 ( 2 -OPr i ) 2 (OPr i ) 8 L 1 ] 3. It is therefore apparent that if the titanium alkoxide starting material is considered as the trimeric unit [Ti 3 (OPr i ) 12 ] then progressive substitution of the alkoxy groups can be achieved, although it is noteworthy that despite repeated attempts using either BIPOL or [C 6 H 9 (OH) 3 ] ligands we have not yet been able to isolate other intermediate trinuclear substituted species, such as [Ti 3 (OPr i ) 8 L 1 2 ], or any derivatives where more than six of the twelve OPr i groups have been substituted.…”

“…In a recent preliminary study we have isolated the trinuclear species [{Ti(OPr i ) 3 } 2 {-Ti(C 6 H 9 O 3 -O 1 ,O 5 ) 2 }] 1 using the cis,ciscyclohexane-1,3,5-trialkoxide ligand (C 6 H 9 O 3 3− ) derived from the corresponding triol [C 6 H 9 (OH) 3 ]. 14 There have been a few reports of other related systems, notably tetranuclear [M 4 (OPr i ) 10 L 2 ] {L = the tridentate anion [CH 3 C(CH 2 O) 3 3− ] derived from 1,1,1-tris(hyd roxymethyl)ethane [CH 3 C(CH 2 OH) 3 ]; M = Ti, Zr}, 15 hexanuclear [Ti 6 O 4 (OPr i ) 8 (OAc) 8 ], 16 and the pentanuclear [Ti 5 (OPr i ) 10 (, 2 17 With reference to the precipitation of insoluble metal oxide aggregates, referred to above, some discrete metal oxoalkoxide species have also been isolated as exemplified by [Ti 3 ( 3 -O)(OPr i ) 9 (OMe)]. 18 In view of the fact that the trinuclear derivative 1 was considerably more resistant to hydrolysis than the parent [Ti(OPr i ) 4 ], it is of interest to determine the extent to which this property is generally applicable in other derivatives related to 1.…”

10 Titanium, zirconium and hafnium

“…37 [ 38 The syntheses of zirconium aryloxides with pendant vinyl groups have been achieved 39 43 An open-chain trinuclear species [{Ti 2 (Pr i O) 3 }{m-Ti(C 6 H 9 O 3 ) 2 }] 3 has been synthesised. 44 [Ti(OPr ] has been used to deposit very uniform thin ¢lms of zirconia. 46 Similarly, [Ti(dpm) 2 (OR) 2 ] (R isobutyl, neopentyl) have been used to form barium strontium titanate ¢lms by MOCVD.…”