Patent ID: 6841668

Claim:
A process for preparing a sterically hindered N-aryloxyamine of formula I, II, III, IV, V or VI which process comprises reacting a sterically hindered nitroxyl compound of formula VII, VIII, IX, X or XI with a diazonium salt of an aromatic amine of formula XII, XIII or XIV in the presence of a polyoxometalate of formula (1) or (2) where M is W(VI) or Mo(VI); or each M is independently selected from W(VI), Mo(VI), V(V), Nb(V) and Ta(V); L is water; X is P, Si, Sn, Ge, As, B, Al, Zn, Co or Fe; M′ is a transition metal of Group 4, 5, 6, 7, 8, 9, 10, 11 or 12, or is a metaloid selected from Al, Si, Ga, Ge, Sn, Sb, Te and Pb; and Y is —CH 2 —, —O—, —S— or —NR 8 — where R 8 is hydrogen or alkyl of 1 to 12 carbon atoms, R 6 and R 7 are independently alkyl of 1 to 8 carbon atoms, or R 6 and R 7 together are tetramethylene or pentamethylene, E 2 is alkylene of 2 to 12 carbon atoms, G is chloro or —N(2-ethylhexyl) 2 , G 1 is —CH 2 —, —CO— or —O—, R is hydrogen, alkyl of 1 to 18 carbon atoms, aralkyl of 7 to 15 carbon atoms, aryl of 6 to 10 carbon atoms, hydroxyl, carboxyl, amino, alkylamino of 1 to 18 carbon atoms, dialkylamino of 2 to 36 carbon atoms, oxo, alkylthio of 1 to 18 carbon atoms, alkoxy of 1 to 18 carbon atoms, aryloxy of 7 to 15 carbon atoms, benzoyloxy, alkylcarbonyloxy of 2 to 18 carbon atoms or alkylcarbonylamino of 2 to 18 carbon atoms, and R 1 to R 5 are independently hydrogen, halogen, nitro, cyano, alkyl of 1 to 18 carbon atoms, aralkyl of 7 to 15 carbon atoms, aryl of 6 to 10 carbon atoms, hydroxyl, carboxyl, alkylthio of 1 to 18 carbon atoms, alkoxy of 1 to 18 carbon atoms, aryloxy of 7 to 15 carbon atoms, alkylcarbonyloxy of 1 to 18 carbon atoms, alkylsulfonyl of 1 to 18 carbon atoms, arylsulfonyl of 6 to 15 carbon atoms, sulfo or —P(O)(OH) 2 or —P(O)(OR 6 ) 2 , or any two vicinal substituents connected together to form a mono or polycyclic ring, so that formula VII can represent inter alia 1-naphthylamine or 2-naphthylamine; or any two vicinal carboxyl groups can be joined to form an imide; or where R, R 6 and R 7 are as defined above.