Ferrocene has been adsorbed on the surface of silica and activated carbon within the pores by dry grinding in the absence of a solvent at room temperature. While the dry adsorption and translational mobility of ferrocene within the pores are already established on the centimeter scale, there is little systematic understanding of the surface site-to-site motions of the ferrocene molecules and their orientation with respect to the surface. In this paper, silica and activated carbon, both widely applied in academia and industry as adsorbents, are used as support materials. Using variable-temperature 13C and 2H solid-state NMR and T 1 relaxation time measurements, the dynamics of ferrocene on the surfaces of silica and activated carbon within the pores has been quantitatively characterized on the molecular scale. The obtained data indicate that ferrocene molecules show a liquid-like behavior on the surface. Fast exchange between isotropically moving molecules and surface-attached molecular states of ferrocene has been found in samples with submonolayer surface coverages. The surface-attached molecular states have been characterized by the free energies ΔG ⧧ of 6.1 kcal/mol for silica and ΔG ⧧ of 6.2 kcal/mol for activated carbon at 223 and 263 K, respectively. The horizontally oriented ferrocene molecules are the most thermodynamically stable states on the surfaces of both materials. These molecules exhibit fast C5 rotation of the Cp rings, as established by low-temperature 13C and 2H NMR. The interactions of ferrocene with the pore surfaces have been characterized by adsorption enthalpies measured as −8.4 to −7.0 kcal/mol and −6.7 kcal/mol for activated carbon and silica, respectively. It has been suggested that the ferrocene–surface interactions for both support materials have a polar character.

Triphenylphosphine oxide (TPPO, 1) has been adsorbed on neutral alumina by dry grinding of the components in the absence of a solvent. The adsorption proves translational mobility of 1 on the surface of alumina. Different surface coverages from a densely packed monolayer (99% coverage) to a dilute sub-monolayer (25%) have been produced. The samples have been studied by diverse multinuclear 1H, 13C, and 31P variable temperature solid-state nuclear magnetic resonance (NMR) techniques. The interactions of 1 with the surface are determined by hydrogen bonding of the P=O group to OH groups on the surface. The 31P solid-state NMR spectra prove that even at low temperatures, the molecules of 1 are highly mobile on the surface. Using T1 and T2 relaxation time analyses of the 31P resonance in the solid state at variable temperatures allowed the identification and quantification of two different modes of mobility. Besides the translational mobility that consists of jumps from one hydrogen-bonding OH site on the surface to an adjacent one, a rotational movement around the axis defined by the P=O group of 1 occurs.

The heptadentate ligand, tris-(2-(2-(methylthio)phenylamino)ethyl)amine (2), has been synthesized from the condensation of nitrilotriacetyl chloride with 2-(methylthio)aniline, to generate 2,2',2"-nitrilotris(N-(2-(methylthio)phenyl)acetamide) (1), followed by a lithium aluminum hydride reduction. The zirconium (3) and hafnium (4) complexes of this ligand were generated via transamination reactions. Both complexes are isostructural, exhibiting a hexadentate N 4 S 2 coordination from the ligand, with one diethylamido ligand also bound. The solid state structures of all compounds are reported.

A modular synthesis of tris(aryl)tren ligands has been demonstrated via the condensation of nitrilotracetyl chloride with different anilines followed by reduction. Varying the aniline in the condensation step from 2-methylthioaniline, to 2-phenylthioaniline, to 2-chloroaniline, generates 2,2',2"-nitrilotris(N-(2-(methylthio)phenyl)acetamide (1), 2,2',2"-nitrilotris(N-(2-(phenylthio)phenyl)acetamide (2) and 2,2',2"-nitrilotris(N-2-chlorophenyl)acetamide (3) respectively. The 2-chloroaniline synthesis is complicated by the production of N-(2chlorophenyl)-3,5-dioxo-1-piperazine-N-(2-chlorophenyl)acetamide (4), but can be adjusted to produce only 3. The reduction of complexes 1-3 proceeds with lithium aluminum hydride for 1 and 2 and with borane for 3 to yield the tris(aryl)tren ligands tris-(2-(2-(methylthio)phenylamino)ethyl)amine (5), tris-(2-(2-(phenylthio)phenylamino)ethyl)amine (6), and tris-(2-(2-chlorophenylamino)ethyl)amine (7). All three of these ligands can be deprotonated with tert-butyllithium for 5 and 7, and n-butyllithium for 6 to generate their trilithium complexes, 8, 9 and 10 for 5, 6 and 7 respectively, with 10 forming two different solvates (10a and 10b). All complexes are characterized by 1 H and 13 C NMR and the solid state structures of complexes 2, 3, 4, 7, 8, 9, 10a and 10b are described.