Acridan derivatives as antioxidants

1. A compound having the following general formula:

wherein R 1 and R 2 together with the carbon atoms to which the are bonded are joined together to form a first substituted or unsubstituted C 3 -C 30 ring,

R 3 and R 5 together with the carbon atoms to which they are bonded are joined together to form a second substituted or unsubstituted C 3 -C 30 ring, and

R 4 , R 5 and R 7 are independently hydrogen, substituted or unsubstituted C 1 -C 30 alkyl group, substituted or unsubstituted C 2 -C 30 alkenyl group, substituted or unsubstituted C 3 -C 12 cycloalkyl group, substituted or unsubstituted C 5 -C 25 aryl group, substituted or unsubstituted C 6 -C 25 arylalkyl group, or substituted or unsubstituted C 1 -C 30 alkoxy group.

2. The compound of claim 1 , wherein where any of the C 3 -C 30 rings, C 1 -C 30 alkyl group, C 2 -C 30 alkenyl group, C 3 -C 12 cycloalkyl group, C 5 -C 25 aryl group, C 6 -C 25 arylalkyl group, or C 1 -C 30 alkoxy group is substituted with one or more substituents, the substituents are selected from hydroxy, halogen, carboxyl, cyano, nitro, oxo, thio, substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted arylalkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted cycloalkenyl, substituted or unsubstituted amino, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted heterocycloalkyl ring, substituted or unsubstituted heteroarylalkyl, substituted or unsubstituted heterocyclic ring, —COOR x , —C(O)NR x R y , —NR x R x , C(O)R x , —SO 2 NR x R x , —OR x , —OC(O)R x , —OC(O)NR x R x ,

—SR x , —SOR x , —SO 2 R x , wherein R x and R x in each comprises a saturated or unsaturated chain of 1 to 30 carbons.

3. The compound of claim 1 , wherein R 1 and R 2 are joined together to form a saturated 5-, 6- or 7-membered ring.

4. The compound of claim 1 , wherein R 1 and R 2 are joined together to form a partially unsaturated or fully unsaturated 5-, 6- or 7-membered ring.

5. The compound of claim 1 of formula (III):

6. The compound of claim 1 of formula (IV):

7. The compound of claim 1 of formula (V):

wherein Z and Y are heteroatoms.

8. The compound of claim 1 of formula (VI):

9. The compound of claim 1 of formula (VII):

10. A lubricating oil composition comprising:

at least one oil of lubricating viscosity; and

an antioxidant improving effective amount of at least one compound of formula (II) of claim 1 .

11. The lubricating oil composition of claim 10 , wherein the at least one oil of lubricating viscosity is selected from the group consisting of engine oils, transmission fluids, hydraulic fluids, gear oils, marine cylinder oils, compressor oils, refrigeration lubricants and mixtures thereof.

12. The lubricating oil composition of claim 10 , further comprising at least one lubricating oil additive selected from the group consisting of antioxidants, anti-wear agents, detergents, rust inhibitors, dehazing agents, demulsifying agents, metal deactivating agents, friction modifiers, pour point depressants, antifoaming agents, co-solvents, package compatibilisers, corrosion-inhibitors, ashless dispersants, dyes, extreme pressure agents and mixtures thereof.

13. The lubricating oil composition of claim 10 , wherein the lubricating oil composition with the at least one lubricating oil additive has a phosphorous content of less than about 0.1 weight percent.

14. The lubricating oil composition of claim 10 , further comprising at least one lubricating oil additive selected from the group consisting of an alkylated diphenylamine, alkylated hindered phenolic, alkylated substituted or unsubstituted phenylenediamine, alkylated oil soluble copper compound, alkylated sulfur containing compound known to impart oxidation stability and mixtures thereof.

15. The lubricating oil composition of claim 14 , wherein the alkylated sulfur containing compound known to impart oxidation stability is selected from the group consisting of phenothiazines, sulfurized olefins, thiocarbamates, sulfur bearing hindered phenolics, zinc dialkyldithiophosphates and mixtures thereof.

16. An additive package comprising about 0.1 to about 75 weight percent of at least one compound of formula (II) of claim 1 .

17. The additive package of claim 16 , wherein the number average molecular weight is greater than 350.

18. A stabilizer-containing composition comprising:

an organic material subject to oxidative, thermal, and/or light-induced degradation and in need of stabilization to prevent or inhibit such degradation; and

a stabilization effective amount of at least one of formula (II) of claim 1 .

19. A method for stabilizing an organic material subject to oxidative, thermal, and/or light-induced degradation and in need of stabilization to prevent or inhibit such degradation, the method comprising adding to the organic material a stabilizing amount of at least one compound of formula (II) of claim 1 .