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(iPrPNHP)Mn(CO)2(OH) (2; iPrPNHP = HN{CH2CH2(PiPr2)}2) was formed from the reversible 1,2-addition of water to (iPrPNP)Mn(CO)2 (1; iPrPNP = the deprotonated, amide form of the ligand, –N{CH2CH2(PiPr2)}2). This reversible reaction was probed via variable-temperature NMR experiments, and the energetics of the 1,2-addition/elimination was found to be slightly exothermic (−0.8 kcal/mol). The corresponding manganese hydroxide was found to react with aldehydes, yielding the corresponding manganese carboxylate complexes (iPrPNHP)Mn(CO)2(CO2R), where R = H, methyl, phenyl. While no reaction between 1 and neat benzaldehyde was observed, in the presence of water, conversion to the corresponding manganese-bound benzoate with formation of H2 was observed. The catalytic oxidation of benzaldehyde by water without additives was unsuccessful due to strong product inhibition, with the manganese benzoate formed under a variety of reaction conditions. Upon addition of base, a catalytic cycle for the conversion of aldehyde t...

Two organometallic 1D infinite coordination polymers and two organometallic monometallic complexes of thorium diazide have been synthesized and characterized. Steric control of these self-assembled arrays, which are dense in thorium and nitrogen, has also been demonstrated: infinite chains can be circumvented by using steric bulk either at the metallocene or with a donor ligand in the wedge.

The molecular geometries and electronic structures of M(η3-allyl)3 [M = Rh, Ir] have been calculated by both hybrid and gradient-corrected density functional theory (DFT). Hybrid DFT (B3LYP) calcul...

The reaction of [Ln(OAr)3]2 with four equivalents of trialkylaluminum leads to the formation of the bis-trialkylaluminum adducts (ArO)Ln[(μ-OAr)(μ-R)AlR2]2 [Ln = La, R = Me (1); Ln = La, R = Et (3); Ln = Sm, R = Et (4)]. The X-ray crystal structure of 1 reveals short La−C(bridging) distances of 2.800(5) and 2.759(5) A. A reduced 1JC-H coupling constant of 110 Hz and a low energy ν(C−H) stretch in the solution and solid state IR spectra are consistent with a strong agostic La···H−C interaction in solution. Crystal data for 1: a = 11.708(2) A; b = 18.416(4) A; c = 20.949(4) A; α = 90°; β = 90°; γ = 90°; V = 4516.8(15) A3; Z = 4; R1 = 4.69%. The solid-state structure of the samarium ethyl derivative 4 reveals close contacts of 2.627(4) and 2.649(4) A between the samarium center and the methylene carbons of the triethylaluminum groups. The room temperature 13C NMR spectrum of 4 exhibits a 1JC-H coupling constant of 102 Hz; additionally, the fluxional process that exchanges methyl groups in 1 and 2 is slow enough on the NMR time scale to allow distinct methylene groups in 4 to be observed. Crystal data for 4: a = 19.318(1) A; b = 20.150(1) A; c = 26.280(1) A; α = 90°; β = 90°; γ = 90°; V = 10229.8(9) A3; Z = 8; R1 = 3.53%. Thermolysis of 1−4 results in ligand redistribution to form [R2Al(OAr)]2 [R = Me, Et (5)] and other unidentified species. Crystal data for 5: a = 9.496(4) A; b = 10.183(4) A; c = 18.794(7) A; α = 90.06(1)°; β = 92.394(7)°; γ = 114.976(6)°; V = 1645.6(11) A3; Z = 2; R1 = 10.13%.

The chiral oxazolidineselone functionality was found to be an excellent partner in the stereospecific acetate aldol reaction with aldehydes via the titanium enolates. Good stereocontrol was obtained as determined by NMR spectroscopy. The oxazolidineselone also provided a straightforward way to establish the stereopurity of the coupling reaction through 77Se NMR spectroscopy.

The chiral oxazolidineselone functionality was found to be an excellent partner in the stereospecific acetate aldol reaction with aldehydes via the titanium enolates. Good stereocontrol was obtained as determined by NMR spectroscopy. The oxazolidineselone also provided a straightforward way to establish the stereopurity of the coupling reaction through 77Se NMR spectroscopy.

We report herein the synthesis and characterization of a lutetium dialkyl complex supported by a multidentate, anilido-pyridine-imine ligand and its subsequent transformation into an unprecedented cationic monoalkyl derivative.