Levay, Krisztina published the artcileTuning the chemoselectivity of the Pd-catalyzed hydrogenation of pyridinecarbonitriles: an efficient and simple method for preparing pyridyl- or piperidylmethylamines, Synthetic Route of 100-70-9, the main research area is pyridinecarbonitrile palladium catalyst hydrogenation; pyridylmethylamine chemoselective preparation; piperidylmethylamine chemoselective preparation.
An effective method for the chemoselective, liquid-phase heterogeneous catalytic hydrogenation of some pyridinecarbonitriles [4-, 3- or 2-pyridinecarbonitrile] to the corresponding pyridyl- or piperidylmethylamines over a Pd/C catalyst was developed. Using our process, not only could an adequate primary amine selectivity to the desired pyridine derivatives [4-, 3- or 2-(aminomethyl)pyridine] be achieved, but it had also been proved to be effective for the selective preparation of piperidylmethylamines [4-, 3- or 2-(aminomethyl)piperidine] by further hydrogenation of the pyridine ring in addition to the nitrile group. The essence of this method was that the synthesis could be fine-tuned by simply adjusting the amount of acidic additive (H2SO4) based on whether the product to be prepared was pyridyl- or piperidylmethylamine. Complete conversions were obtained under mild conditions (30-50°C, 6 bar), in all cases, but the very high selectivity to 2-(aminomethyl)piperidine or 2-(aminomethyl)pyridine (98 and 93%, resp.) decreased to 76% (3-(aminomethyl)piperidine) and 72% (3-(aminomethyl)pyridine), as well as 10% (2-(aminomethyl)piperidine) and 57% (2-(aminomethyl)pyridine) by changing the position of the nitrile group in the pyridine ring. The possible reasons for the diversed primary amine selectivities observed in the hydrogenation of the constitutional isomers of pyridinecarbonitriles were confirmed by quantum chem. calculations (DFT). Adsorption energy profiles regarding the interactions between the nitrile starting materials, imine intermediates or amine products and palladium were computed to clarify the selectivity changes.
Catalysis Science & Technology published new progress about Adsorption energy. 100-70-9 belongs to class nitriles-buliding-blocks, name is Picolinonitrile, and the molecular formula is C6H4N2, Synthetic Route of 100-70-9.
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts