Nickel-Catalyzed Hydrogenolysis and Conjugate Addition of 2-(Hydroxymethyl)pyridines via Organozinc Intermediates
作者:Luke E. Hanna、Michael R. Harris、Kenji Domon、Elizabeth R. Jarvo
DOI:10.1021/acs.orglett.7b03049
日期:2017.12.1
proposed to proceed through secondary benzylzinc reagents. Quenching with deuteromethanol provides straightforward incorporation of a deuterium label in the benzylic position. Intramolecular conjugateadditions with α,β-unsaturated esters are also demonstrated and support the intermediacy of a benzylzinc complex.
A short, scalable and environmentally benignsynthesis of 2- and 4-substitutedbenzylpiperidines has been developed. The method is based on the temperature-programmed consecutive deoxygenation and heteroaromatic ring saturation of aryl(pyridin-2-yl)- and aryl(pyridin-4-yl)methanols and aryl(pyridin-4-yl)methanones in the presence of Pd/C catalyst. The crucial roles of the temperature, the acidity and