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Molybdenum oxides (MoO3 − x, x = 1, 2, and 3) with three types of morphologies were prepared and applied to the reaction of benzyl alcohol with dimethylformamide (DMF) for synthesis of tertiary amines. The MoO3 − 1 catalyst prepared by direct calcination exhibited high activity and tertiary amines selectivity in the N,N‐dimethylamination of benzyl alcohol under the reaction conditions at 150°C for 12 h using DMF as a methylating agent and solvent, as compared to MoO3 − 2 and MoO3 − 3 catalysts. This feature was ascribed to the high proportion of surface chemisorbed oxygen for MoO3 − 1 sample, which can promote the adsorbed benzyl alcohol transformation into benzaldehyde. The MoO3 − 1 catalyst was also found to be reusable in five consecutive runs without a significant decrease in catalytic activity. In addition, control experiments showed two parallel reaction routes in this catalytic system. One route is the reaction of benzaldehyde intermediate and DMF to form tertiary amines (Route I); the other route is that benzyl formate intermediate reacted with DMF (Route II), which has not been reported before and specifically involves the esterification of benzyl alcohol with formic acid from DMF decomposition to form benzyl formate. [ABSTRACT FROM AUTHOR]

Biaryl skeletons were directly constructed via palladium-catalyzed ortho-arylation of N, N-dimethyl benzylamine with aryl boronic acids with high efficiency and high regioselectivity under open-flask conditions. The N,N-dimethylaminomethyl group was first applied as a directing group in such an oxidative coupling. Various substrates proved to be efficient coupling partners, furnishing the corresponding ortho-monoarylated or -diarylated arenes in moderate to good yields under mild conditions. [ABSTRACT FROM AUTHOR]

Reaction of {[Pd(dmba)(μ-Cl)]2} (dmba = (CH3)2NCH2C6H4) with an in situ generated N-heterocyclic carbene (NHC = 1,3-dimesitylimidazolidin-2-ylidene) afforded crystals containing [chloro-(1,3-dimesitylimidazolidin-2-ylidene)(N,N-dimethylaminobenzyl-C1,N)palladium(II)] (VII). Molecular and crystal structures of the title compound have been determined by single crystal X-ray diffraction technique. Complex VII crystallizes in space group P 1, with a = 13.685(3) Å, b = 13.590(2) Å, c = 16.229(3) Å, α = 87.162(13)°, β = 70.514(15)°, γ = 84.153(16)°, Z = 4, DCalcd = 1.367 g cm-3. There are two independent molecules in the asymmetric unit. [ABSTRACT FROM AUTHOR]

Abstract: [11C]N,N-Dimethyl-2-(2′-amino-4′-ethylphenylthio)benzylamine ([11C]EADAM) was synthesized in the development of a serotonin transporter (SERT) imaging ligand for positron emission tomography (PET). The methods of ligand synthesis, results of in vitro characterization, 11C labeling and in vivo micro-PET imaging studies of [11C]EADAM in cynomolgus monkey brain are described. 11C was introduced into N,N-dimethyl-2-(2′-amino-4′-ethylphenylthio)benzylamine () by alkylation of N-methyl-2-(2′-amino-4′-ethylphenylthio)benzylamine () in 32% radiochemical yield (end of bombardment [EOB], decay-corrected from [11C]methyl iodide). Competition binding assays in cells stably expressing the transfected human dopamine transporter (DAT), SERT and norepinephrine transporter (NET) labeled with [3H]WIN 35428 or [125I]RTI-55, [3H]citalopram and [3H]nisoxetine, respectively, indicated the following order of SERT affinity: ADAM>EADAM≫fluvoxamine. The affinity of EADAM for DAT and NET was 500- and >1000-fold lower, respectively, than for SERT. Micro-PET brain imaging studies in a cynomolgus monkey demonstrated high [11C]EADAM uptake in the striatum, thalamus and brainstem. [11C]EADAM uptake in these brain regions peaked in less than 60 min following administration of [11C]EADAM. The tissue-to-cerebellum ratios of the striatum, thalamus and brainstem were 1.67, 1.71 and 1.63, respectively, at 120 min postinjection of [11C]EADAM. Analysis of monkey arterial plasma samples using high-pressure liquid chromatography determined there was no detectable formation of lipophilic radiolabeled metabolites capable of entering the brain. In a displacement experiment with citalopram in a cynomolgus monkey, radioactivity in the striatum, thalamus and brainstem was displaced 20–60 min after administration of citalopram. In a blocking experiment with citalopram in a cynomolgus monkey, radioactivity in the striatum, thalamus and brainstem was significantly reduced. These results support the candidacy of [11C]EADAM as a radioligand for visualizing brain SERT using PET. [Copyright &y& Elsevier]

The X-ray crystal structures of cyclopalladated complexes are reported. Reaction of {[Pd(dmba)(μ-Cl)]2}, (1), (dmba=N(CH3)2CH2C6H5) with triphenylphosphine gave crystals containing {chloro–(triphenylphosphino)-bis[N,N-dimethylaminobenzyl-C1,N]palladium(II)} (2a) and {trans-bis(triphenylphosphino)-chloro-[N,N-dimethylaminozyl-C]palladium(II)} (2b). Complex (1) crystallises in the space group P2(1)/c with a=7.849(1) A˚, b=15.635(3) A˚, c=8.352(1) A˚, β=109.29°, and Dcalc=1.895 g cm −3 for Z=2. Complexes (2a) and (2b) crystallize together in the space group P2(1)/n with a=9.964(2) A˚, b=34.228(5) A˚, c=18.127(3) A˚, β=91.91 °, and Dcalc=1.439 g cm−3. [Copyright &y& Elsevier]

Dimethylbenzylamine (DMBA) is used in the production of epoxy resins. The aims of this study were to assess occupational exposure to DMBA and evaluate the usefulness of monitoring the urinary excretion of DMBA and DMBA metabolites as indicators of exposure to DMBA. A sensitive gas chromatographic method for analysis of DMBA in air and in urine has been developed. The detection limit for DMBA in air for a 60-l air sample collected in 10 ml absorption solution was 2 μg/m and in charcoal tubes, 0.3 μg/m. The detection limit for DMBA in urine was 0.02 mg/l. Ten male workers manufacturing epoxy resin were monitored during a full shift in the working environment and urine samples were collected at the end of exposure. The mean exposure and the highest DMBA concentration observed in air were 18 μg/m (time-weighted average; range 3-48 μg/m) and 91 μg/m, respectively. The DMBA concentrations in the urine samples were below the detection limit. After reduction of the urine samples the DMBA concentrations in the urine samples were below the detection limit. After reduction of the urine samples the DMBA concentrations (U-SumDMBA) ranged from 0.02 to 0.22 mg/l. There was significant correlation between the exposure to DMBA and the U-SumDMBA. This observation suggests that the U-SumDMBA in urine samples collected at the end of a shift is a useful indicators of occupational exposure to DMBA. [ABSTRACT FROM AUTHOR]