Inorganic Chemistry, Vol.36, No.3, 278-283, 1997
Alkoxido, Amido, and Imido Derivatives of Titanium(IV) Tetratolylporphyrin
Treatment of (TTP)TiCl2 (1) [TTP = meso-5,10,15,20-tetra-p-tolylporphyrinato dianion] with excess NaOR (R = Ph, Me, t-Bu) affords the bis(alkoxide) derivatives (TTP)Ti(OR)(2) [R = Ph (2), Me (3), t-Bu (4)] in moderate yield. The corresponding amido derivative (TTP)Ti(NPh(2))(2) (5) is prepared in an analogous fashion employing LiNPh(2). The disubstituted complexes 2, 3, and 5 react cleanly with (TTP)TiCl2 to afford the ligand exchange products (TTP)Ti(OR)Cl [R = Ph (6), Me (7)] and (TTP)Ti(NPh(2))Cl (8), respectively. The monosubstituted complexes 6-8 are also obtained by treatment of 1 with 1 equiv of the appropriate NaOR or LiNPh(2) reagent. Treatment of 5 with excess phenol produces the bis(phenoxide) derivative 2 and 2 equiv of HNPh(2). The imido derivatives (TTP)Ti = NR[R = t-Bu (9), Ph (10), C6H4-p-Me (11)] are prepared by the treatment of 1 with excess LiNHR. The t-Bu derivative (9) is also obtained by reaction of 1 with excess H2N-t-Bu at elevated temperatures. The phenyl imido complex (10) may be produced by the reaction of 0.5 equiv of PhN = NPh with (TTP)Ti(eta(2)-EtC = CEt) in refluxing toluene. Finally, (TTP)Ti = NTMS (12) is obtained by oxidation of (TTP)Ti(eta(2)-EtC = CEt) with N(3)TMS.
Keywords:TRANSITION-METAL PORPHYRINS;ALKYNE 2+2 CYCLOADDITIONS;X-RAY STRUCTURE;C-H ACTIVATION;SYNTHETIC APPLICATIONS;COMPLEXES;REACTIVITY;CONCISE;LIGANDS