Obdyakov, V. F. published the artcileStabilization of palladium in homogeneous chlorideless catalysts of oxidation of olefins C2-C4 by oxygen into carbonyl compounds, HPLC of Formula: 636-73-7, the publication is Kataliz v Promyshlennosti (2007), 19-25, database is CAplus.
The first step of homogeneous oxidation of olefins C2-C4 by oxygen in the presence of catalyst Pd + GPK-x, were GPK-x is phosphovanadomolybdic heteropoly acid H3+xPVVx Mo12-xO40, consist in reduction of GPK-x with olefin in the presence Pd-complexes at 30-60° into HmGPK-x where m=[VIV]∑/[GKP-x] – is excellent reduction catalyst. In this case the redox-system Pd12/Pd02 works and with increasing of temperature in converts into system Pd2+/PdMET with higher redox-potential. During this transformation interval of values m is diminished where the catalyst remained as homogeneous and from reduced solution metallic Pd begins to precipitate To prevent the Pd precipitation it needs to introduce in catalyst the stabilizers stable from oxidation As stabilizers can be used 3-pyridinesulfonic acid of more cheaper 2,6-pyridinecarboxylic (dipicolinic) acid (I). In the presence of the stabilizers the activity of catalyst is diminished but the area of its homogeneity will extend. Complexes of Pd with I are stable at temperatures of regeneration of catalyst (150-160°). Therefore I is considered as rather perspective stabilizer of Pd in catalysts Pd + GPK-x and can be used in industrial homogeneous processes of oxidation of olefins C2-C4 with oxygen.
Kataliz v Promyshlennosti published new progress about 636-73-7. 636-73-7 belongs to pyridine-derivatives, auxiliary class Pyridine,Sulfonic acid, name is Pyridine-3-sulfonic acid, and the molecular formula is C5H5NO3S, HPLC of Formula: 636-73-7.
Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem