Thiol-formyl hemiacetal corrosion inhibitors

1. A method of inhibiting corrosion at a surface, the method comprising:

contacting the surface with an effective amount of an anti-corrosion composition, wherein the surface is part of equipment used in the production, transportation, storage, and/or separation of crude oil or natural gas; the composition comprising:

a compound of formula (IA)

wherein

R 1 is alkyl, aryl, or alkenyl;

n is an integer from 1 to 10;

R 2 is hydrogen, alkyl, alkenyl, or aryl; and

R 3 is hydrogen, alkyl, alkaryl, aryl, or heterocyclo.

2. The method of claim 1 , wherein the anti-corrosion composition comprises the compound of formula (IA).

3. The method of claim 2 , wherein R 1 of Formula (IA) is either:

C 1 -C 24 alkyl, C 1 -C 24 alkenyl, C 6 -C 12 aryl, or C 3 -C 8 cycloalkyl, wherein said alkyl, alkenyl, aryl, or cycloalkyl are each independently unsubstituted or substituted with 1 to 3 substituents independently selected from —F, —Cl, —NO 2 , —CN, —OH, —NH 2 , C 1 -C 6 haloalkyl, C 1 -C 6 alkoxy, —CO 2 R 10 , and —CON(R 11 ) 2 , wherein R 10 and R 11 , at each occurrence, are each independently hydrogen or C 1 -C 6 alkyl; or optionally one or more of the —CH 2 — groups of R 1 is replaced with a —C(O)O— group; or

C 1 -C 18 alkyl, or C 3 -C 8 cycloalkyl, wherein said alkyl, or cycloalkyl are each independently unsubstituted or substituted with 1 to 3 substituents independently selected from —OH, C 1 -C 6 alkoxy, or —CO 2 R 10 , wherein R 10 at each occurrence, is independently hydrogen or C 1 -C 6 alkyl; or optionally one or more of the —CH 2 — groups of R 1 is replaced with a —C(O)O— group.

4. The method of claim 2 , wherein R 1 of Formula (IA) is

C 1 -C 18 alkyl or C 3 -C 8 cycloalkyl.

5. The method of claim 4 , wherein R 2 of Formula (IA) is hydrogen.

6. The method of claim 5 , wherein n of Formula (IA) is 1 to 5.

7. The method of claim 6 , wherein R 3 of Formula (IA) is hydrogen, methyl, ethyl, propyl, or phenyl.

8. The method of claim 1 , wherein the anti-corrosion composition further comprises one or more additional corrosion inhibitors, solvents, asphaltene inhibitors, paraffin inhibitors, scale inhibitors, emulsifiers, water clarifiers, dispersants, emulsion breakers, gas hydrate inhibitors, biocides, pH modifiers, or surfactants.

9. The method of claim 1 , wherein the anti-corrosion composition comprises from about 0.1 to about 20 wt. % of one or more compounds of formula (IA) in a 1:1 water:glycol ether solvent system.

10. The method of claim 2 , wherein R 1 of Formula (IA) is C 1 -C 12 alkyl optionally substituted with 1 to 3 substituents of —OH or —CO 2 H; or R 1 is C 1 -C 12 alkyl wherein one or more of the —CH 2 — groups is replaced with a —C(O)O— group.

11. The method of claim 2 , wherein R 1 of Formula (IA) is C 1 -C 12 alkyl substituted with 1 to 3 substituents of —OH or —CO 2 H; or R 1 is C 1 -C 12 alkyl wherein one or more of the —CH 2 — groups is replaced with a —C(O)O— group.

12. The method of claim 2 , wherein R 1 of Formula (IA) is linear C 1 -C 10 alkyl substituted with a terminal —OH group.

13. The method of claim 2 , wherein R 1 of Formula (IA) is linear C 1 -C 10 alkyl substituted with a terminal —CO 2 H group.

14. The method of claim 2 , wherein R 1 of Formula (IA) is linear C 1 -C 10 alkyl wherein one of the —CH 2 — groups is replaced with a —C(O)O— group.

15. The method of claim 2 , wherein R 1 of Formula (IA) is —CH 2 —CH 2 —OH, cyclohexyl, —(CH 2 ) 6 —OH, propyl, dodecyl, —CH 2 CH(OH)CH 2 OH, —CH(C(O)OH)CH 2 C(O)OH, —(CH 2 ) 2 C(O)OCH 2 CH(C 2 H 5 )C 4 H 9 , or —(CH 2 ) 2 C(O)OH.

16. The method of claim 2 , wherein R 3 of Formula (IA) is hydrogen.

17. The method of claim 5 , wherein R 3 of Formula (IA) is hydrogen.

18. The method of claim 17 , wherein R 1 of Formula (IA) is —CH 2 —CH 2 —OH.

19. The method of claim 17 , wherein R 1 of Formula (IA) is cyclohexyl, propyl,

dodecyl, —CH 2 CH(OH)CH 2 OH, —CH(C(O)OH)CH 2 C(O)OH, —(CH 2 ) 2 C(O)OCH 2 CH(C 2 H 5 )C 4 H 9 , or —(CH 2 ) 2 C(O)OH.