Preparation of N-phenyl-benzoquinoneimine from hydroxydiphenylamines
AssigneeFlexsys America L.P.
InventorsDonald L. Fields, Jr., Michael K. Stern, Jayant Shivji Lodaya
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Abstract
A hydroxydiphenylamine compound can be converted to an N-phenylquinoneimine by reacting the hydroxydiphenylamine with oxygen or an oxygen containing gas in the presence of a modified activated carbon catalyst, the catalyst having had surface oxides removed therefrom.
Claims21
A process for preparing an N-phenylquinone-imine (NPQI) comprising oxidizing a corresponding hydroxydiphenylamine (HDA) in the presence of oxygen or an oxygen containing gas and a modified activated carbon catalyst, with said catalyst having been modified by having surface oxides removed therefrom.
A process for production of an N-phenylquinone-imine comprising:
- (a) providing a hydroxydiphenylamine in a solvent system;
- (b) oxidizing said hydroxydiphenylamine in the presence of oxygen or an oxygen containing gas and a modified activated carbon catalyst to form an N-phenylquinone-imine;
- (c) filtering the modified activated carbon catalyst from the resulting product of step (b);
- and
- (d) isolating the N-phenylquinone-imine from the resulting product of step (c);
- wherein said modified activated carbon catalyst is characterized by having had surface oxides removed therefrom.
Dependencies are inferred from the claim text.