Process for producing lactone

1. A method for producing a γ-butyrolactone, which comprises:

reacting a 4-halo-butylamide of Formula (II):

wherein X represents a halogen atom, and R 1 to R 6 each independently represents a hydrogen atom or any desired substituent,

with an aqueous medium at a pH of 2 to 4.5 to give a γ-butyrolactone of Formula (III):

wherein R 1 to R 6 each independently represents a hydrogen atom or any desired substituent, and

wherein the 4-halo-butylamide of Formula (II) is a 4-halo-3-hydroxybutylamide; or wherein the 4-halo-butylamide of Formula (II) is produced by nitrile hydratase treatment of a 4-halo-butyronitrile having Formula (IV):

wherein X represents a halogen atom, and R 1 to R 6 each independently represents a hydrogen atom or any desired substituent.

2. The method according to claim 1 , wherein the 4-halo-butylamide of Formula (II) is a 4-halo-3-hydroxybutylamide.

3. The method according to claim 1 , wherein the 4-halo-butylamide of Formula (II) is produced by nitrile hydratase treatment of a 4-halo-butyronitrile having Formula (IV):

wherein X represents a halogen atom, and R 1 to R 6 each independently represents a hydrogen atom or any desired substituent.

4. The method according to claim 3 , wherein nitrile hydratase is produced by a transformant carrying a gene encoding nitrile hydratase.

5. A method for producing a δ-valerolactone, which comprises:

reacting a 5-halo-pentylamide of Formula (V):

wherein X represents a halogen atom, and R 1 to R 8 each independently represents a hydrogen atom or any desired substituent,

with an aqueous medium to give a δ-valerolactone of Formula (VI):

wherein R 1 to R 8 each independently represents a hydrogen atom or any desired substituent.

6. The method according to claim 2 , wherein the reaction is carried out at a temperature of 30° C. to 100° C.

7. The method according to claim 5 , wherein the reaction is carried out at a temperature of 30° C. to 100° C.

8. A method for producing a lactone, which comprises:

reacting an aqueous medium with an amide compound of Formula (I) to produce a lactone;

wherein Formula (I) is:

wherein

X represents a halogen atom; n is an integer of 0, 1 or 2, and R, R′ and R 1 to R 6 each independently represents a hydrogen atom or any desired substituent;

wherein n represents an integer of 1 or 2, or wherein X represents a halogen atom other than iodine, or wherein at least one of R, R′, R 1 , R 2 , R 3 , R 4 , R 5 , or R 6 is not hydrogen.

9. The method of claim 8 , wherein n is 1 or 2.

10. The method of claim 9 , wherein X represents a halogen atom other than iodine.

11. The method of claim 8 , wherein at least one of R, R′, R 1 , R 2 , R 3 , R 4 , R 5 , or R 6 is not hydrogen.

12. The method of claim 8 , which is conducted at an acidic pH.

13. The method of claim 8 , which is conducted at a pH ranging between 2 and 4.5.

14. A method for producing a ε-caprolactone which comprises:

reacting a 6-halo-hexylamide of Formula (I):

wherein n=2; X represents a halogen atom, and R, R′ and R 1 to R 6 each independently represents a hydrogen atom or any desired substituent;

with an aqueous medium at a pH of 2 to 4.5 to give a ε-caprolactone.

15. The method of claim 14 , wherein the 6-halo-hexylamide is produced by nitrile hydratase treatment of the corresponding nitrile.