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Updated: Oct 3, 2026

Synthesis and Reaction Chemistry of Nanosize Monosodium Titanate
Published on: February 23, 2016
Acid-Base Adducts of Catalytically Active Titanium(IV) Lewis Acids
Andrew O. Larsen1, Peter S. White, Michel R. Gagné
1Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290.
Abstract:
A series of monomeric Lewis acid-base adducts of the Diels-Alder catalyst Ti(O-2,6-Me(2)C(6)H(3))(2)Cl(2) have been synthesized from bidentate diphosphines and diamines, Ti(O-2,6-Me(2)C(6)H(3))(2)Cl(2)L(2) (L(2) = dmpe, depe, dpeda, and dmeda). X-ray crystal structures of Ti(O-2,6-Me(2)C(6)H(3))(2)Cl(2)(dmpe) and Ti(O-2,6-Me(2)C(6)H(3))(2)Cl(2)(dpeda) establish a distorted octahedral coordination environment with trans-chloride ligands. Bidentate ligands that were also studied but did not form isolable complexes with the Ti(IV) Lewis acid include dppe, tmeda, and binam. Through pairwise exchange reactions a qualitative ranking of relative bidentate ligand binding strengths to the Lewis acid were obtained (dmeda >/= dpeda > dmpe >/= depe > tmeda > binam > dppe). The ranking is readily rationalized using hard-soft electronic arguments except for tmeda, which requires that unfavorable steric interactions be invoked.
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