The reactions of AlMe3, BEt3, and ZnEt2 with toluene solutions of the copper(II) complexes [CuL2] {L = acetylacetonate (acac; 1), hexafluoroacetylacetonate (hfac; 2), N-isopropyl-β-ketiminate (acnac; 3), N,N-dimethyl-β-diketiminate (nacnac; 4), 2-pyrrolylaldehyde (PyrAld; 5), N-isopropyl-2-pyrrolylaldiminate (PyrIm iPr; 6a), N-ethyl-2-pyrrolylaldiminate (PyrImEt; 6b), and N-isopropyl-2-salicylaldiminate (IPSA; 7)} were investigated, and most combinations were found to deposit metal films or metal powder at 50 °C or less. SEM and XPS of metal films deposited on ruthenium showed a range of morphologies and compositions, including pure copper (excluding oxygen content after atmospheric exposure). These nonaqueous solution screening studies provided a rapid and convenient means to identify the most promising [CuIIL2] precursor/ER n co-reagent combinations for copper metal ALD/pulsed-CVD studies, and subsequent ALD/pulsed-CVD studies were performed using 6b in combination with AlMe3, BEt3 and ZnEt2. As in solution, the reactivity of these reagents (pulsed-CVD) followed the order ZnEt2 ≈ AlMe3 ≫ BEt3. Furthermore, at 120−150 °C, ZnEt2 was used successfully to deposit smooth, conductive films composed of copper with 8−15% Zn. On the basis of CVD studies with ZnEt2, zinc content appears to derive from a parasitic CVD process, which becomes more favorable above 120 °C, detracting from the goal of self-limiting deposition.

The solution reactions of bis(N-isopropylpyrrolylaldiminate)copper(II) (CuL 2 ) with AlMe 3 , BEt 3 , and ZnEt 2 have been studied. In all cases, reduction occurs in two stages via a stable copper(I) pyrrolylaldiminate complex (Cu 2 L 2 ), with each stage initiated by copper alkyl complex formation. Reduction from "LCuR" (R=Me or Et) occurs with release of R 2 or L-R, consistent with bimolecular C-C or C-N bond-forming reductive elimination. At room temperature or below, copper deposition from "CuMe" occurs exclusively via reductive elimination of ethane, whereas decomposition of "CuEt" yields ethylene, ethane, and hydrogen, indicative of both β-hydride elimination and reductive elimination. The reaction byproducts [Cu 2 L 2 ], [LAlMe 2 ], [L 2 AlMe], [AlL 3 ], [LBEt 2 ], [LZnEt], [ZnL 2 ], L-Me, and L-Et were synthesized independently and isolated as pure compounds. All compounds are thermally stable, with the exception of LZnEt, which undergoes ligand redistribution to form ZnL 2 and ZnEt 2 in solution and as a solid at elevated temperatures. With the exception of [LZnEt] and [Cu 2 L 2 ], these complexes are also volatile; monoligated [LAlMe 2 ] and [LBEt 2 ] are particularly volatile, and therefore more desirable as byproducts in ALD or pulsed-CVD.

A bis-pyrrolide ligand containing a nonconjugated aromatic ring in the backbone was reacted with ThCl 4 (DME) 2 , affording the corresponding η 6 -{1,3-[(2-C 4 H 3 N)(CH 3 ) 2 C] 2 C 6 H 4 }ThCl 3 ][Li(DME) 3 ] (1) complex. In this species, the π-bonding interaction of the actinide with the ring is probably induced by steric constraint. The bonding mode of the pyrrolide rings was switched from σ to π upon treatment of complex 1 with Et 3 Al. This reaction was also accompanied by deprotonation of the aromatic ring and formation of two similar compounds with the ring σ-bonded to the Th metal center. The two compounds {were isolated and fully characterized. The common feature among these two species is that the switching of bonding mode of the pyrrolide rings, resulting from the coordination of the aluminum residues, is accompanied by deprotonation of the central ring. Attempts to reduce 1 yielded the paramagnetic 3), which on the basis of the connectivity might be regarded as a rare case of Th(III). However, DFT calculation have elucidated the electronic structure of this species, which should be regarded as containing tetravalent Th bonded to the ligand radical anion. The spin density is mainly localized at the ring C atom, which is deformed and deviates from the planarity. Similar reductions carried out under slightly different reaction conditions afforded {η 4). In this complex the metal is surrounded by two ligands, one of which appears as having been partly hydrogenated at the central aromatic ring. Treatment of an in situ generated transient low-valent species with azobenzene as mild oxidizing agent resulted in reoxidation to a tetravalent thorium diphenylhydrazido species, [{η 6 -1,3-[(η 5 -2-C 4 H 3 N)(CH 3 ) 2 C] 2 C 6 H 4 }Th(μ-η 2 -PhNNPh)(μ-Cl)(Cl)Li(DME)][Li(DME) 3 ] (5).

Very stable in operando and low‐loaded atomic molybdenum on solid‐support materials have been prepared and tested to be catalytically active for N2‐into‐NH3 hydrogenation. Ammonia synthesis is reported at atmospheric pressure and 400 °C with NH3 rates of approximately 1.3×103 μmol h−1 gMo−1 using a well‐defined Mo‐hydride grafted on silica (SiO2‐700). DFT modelling on the reaction mechanism suggests that N2 spontaneously binds on monopodal [(≡Si−O‐)MoH3]. Based on calculations, the fourth hydrogenation step involving the release of the first NH3 molecule represents the rate‐limiting step of the whole reaction. The inclusion of cobalt co‐catalyst and an alkali caesium additive impregnated on a mesoporous SBA‐15 support increases the formation of NH3 with rates of circa 3.5×103 μmol h−1 gMo−1 under similar operating conditions and maximum yield of 29×103 μmol h−1 gMo−1 when the pressure is increased to 30 atm.