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The luminescent properties of Au(I) and Pt(II) compounds are commonly tuned by exploiting the alkynyl ligand with varying electron density. Herein, we describe the synthesis of three new emissive transition metal compounds, tbpyPt(C2pym)2, Ph3PAuC2pym, and Cy3PAuC2pym (where HC2pym = 2-ethynylpyrimidine), verified by 1H-NMR, EA, and a single-crystal X-ray diffraction analysis. The tbpyPt(C2pym)2 complex crystallized as an Et2O solvate in the orthorhombic space group Pbca with Z = 24 with three unique Pt(II) species within the unit cell. The Cy3PAuC2pym species crystallizes in a monoclinic space group with one unique complex in the asymmetric unit. Changing the identity of the phosphine from Cy3P to Ph3P influences interactions within the unit cell. Ph3PAuC2pym, which also crystalizes in a monoclinic space group, has an aurophilic bonding interaction Au–Au distance of 3.0722(2) Å, which is not present in crystalline Cy3PAuC2pym. Regarding optical properties, the use of an electron-deficient heterocycle provides an alternate approach to blue-shifting the emission of Pt(II) transition metals’ compounds, where the aryl moiety is made more electron-deficient by exploiting nitrogen within this moiety instead of the typical strategy of decorating the aryl ring with electron withdrawing substituents (e.g., fluorines). This is indicated by the blue-shift in emission that occurs in tbpyPt(C2pym)2 (λmax, emission = 512 nm) compared to the previously reported tbpyPt(C22-py)2 (where HC22-py = 2-ethynylpyridine) complex (λmax, emission = 520 nm). 

Bis[η 5 -( tert -butoxycarbonyl)cyclopentadienyl]dichloridotitanium(IV), [Ti(C 10 H 13 O 2 ) 2 Cl 2 ], was synthesized from LiCp COO t -Bu using TiCl 4 , and was characterized by single-crystal X-ray diffraction and 1 H NMR spectroscopy. The distorted tetrahedral geometry about the central titanium atom is relatively unchanged compared to Cp 2 TiCl 2 . The complex exhibits elongation of the titanium–cyclopentadienyl centroid distances [2.074 (3) and 2.070 (3) Å] and a contraction of the titanium–chlorine bond lengths [2.3222 (10) Å and 2.3423 (10) Å] relative to Cp 2 TiCl 2 . The dihedral angle formed by the planes of the Cp rings [52.56 (13)°] is smaller than seen in Cp 2 TiCl 2 . Both ester groups extend from the same side of the Cp rings, and occur on the same side of the complex as the chlorido ligands. The complex may serve as a convenient synthon for titanocene complexes with carboxylate anchoring groups for binding to metal oxide substrates.