Synthesis of Agomelatine by One-pot Catalytic Hydrogenation and Acetylation with NiO

Nano-NiO and bulk NiO were prepared from Ni(AC)_2·4 H_2O by coordination precipitation using aqueous ammonia and by a solid state reaction, respectively. The nickel oxide particles were characterized by X-ray Diffraction(XRD) and scanning electron microscopy(SEM). The results indicate that nano-sized NiO has a crystal phase with a standard face-centered cubic lattice structure, with a mean particle diameter of about 10 nm. The evaluation of the activity of nickel oxide nanoparticles in the catalytic hydrogenation of 7-methoxy-1-naphthylacetonitrile was carried out. The results demonstrate the efficient synthesis of the title compound by a one-pot catalytic hydrogenation and acetylation with NiO. The NiO nanoparticles displayed superior catalytic activity in the synthesis of agomelatine in the one-pot reaction.The total yield of agomelatine is over 81.8% with a purity of 99.2%, as determined by HPLC. The structure of agomelatine was confirmed by IR, MS, and 1 H NMR analysis.

NitroMAC：An instrument for the measurement of HONO and intercomparison with a long-path absorption photometer

Nitro MAC（French acronym for continuous atmospheric measurements of nitrogenous compounds） is an instrument which has been developed for the semi-continuous measurement of atmospheric nitrous acid（HONO）. This instrument relies on wet chemical sampling and detection using high performance liquid chromatography（HPLC）-visible absorption at540 nm. Sampling proceeds by dissolution of gaseous HONO in a phosphate buffer solution followed by derivatization with sulfanilamide/N-（1-naphthyl）-ethylenediamine. The performance of this instrument was found to be as follows： a detection limit of around 3 ppt with measurement uncertainty of 10% over an analysis time of 10 min. Intercomparison was made between the instrument and a long-path absorption photometer（LOPAP） during two experiments in different environments. First, air was sampled in a smog chamber with concentrations up to 18 ppb of nitrous acid. Nitro MAC and LOPAP measurements showed very good agreement. Then, in a second experiment, ambient air with HONO concentrations below250 ppt was sampled. While Nitro MAC showed its capability of measuring HONO in moderate and highly polluted environments, the intercomparison results in ambient air highlighted that corrections must be made for minor interferences when low concentrations are measured.