Hydrodemetallation of nickel and vanadium porphyrins: separation and characterization of reaction intermediates

摘要

It is well known that the catalytic hydrodemetallation (HDM) reaction mechanism of nickel and vanadyl etioporphyrin (NiETIO and VOETIO) is a sequential mechanism (1-4). Recently, out work (5-6) showed that the catalytic HDM reaction mechanism of nickel and vanadyl octaethylporphyrin (NiOEP and VOOEP) is similar to that of NiETIO and VOETIO. In order to obtain more knowledge about reaction intermediates, Agrawal and Wei (2) isolated them using column chromatography, and then identified the nickel intemediates by mass spectroscopy (MS). However, as the vanadium intermediates are highly unstable, they weren't analyzed with MS. In the present work, we isolated the reaction intermediates of NiOEP and VOOEP HDM using an improved column chromatographic method, and subsequently identified the nickel and vanadium intermediates by MS.