Processes and intermediates for making sweet taste enhancers

1. A process of preparing a compound having structural Formula (I):

comprising reacting a compound having structural Formula (II)

with a base or an activating reagent,

wherein

R 1 is —CN or —C(O)NH 2 ; and

X is alkyl, substituted alkyl, alkenyl, substituted alkenyl, heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substituted heteroalkenyl.

2. The process of claim 1 , comprising reacting a compound having structural Formula (IIa)

with an activating reagent to provide the compound of Formula (I).

3. The process of claim 1 , comprising reacting a compound having structural Formula (IIb)

with a base to provide the compound of Formula (I).

4. A process of preparing a compound having structural Formula (I):

comprising reacting a compound having structural Formula (III)

with NH 2 S(O) 2 NH 2 or Cl—S(O) 2 —NH 2 optionally in the presence of a base, to provide directly the compound having structural Formula (I), or alternatively to provide the compound having structural formula (II) of claim 1 which is further reacted with an inorganic base or an activating reagent to provide the compound having structural Formula (I),

wherein

R 1 is —CN or —C(O)NH 2 ; and

X is alkyl, substituted alkyl, alkenyl, substituted alkenyl, heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substituted heteroalkenyl.

5. A process of preparing a compound having structural Formula (I):

comprising reacting a compound having structural Formula (VII)

with NH 3 or NH 3 .H 2 O;

wherein

X is alkyl, substituted alkyl, alkenyl, substituted alkenyl, heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substituted heteroalkenyl; and

R 7 is a leaving group selected from the group consisting of halo, —OMs, —OTs, and —OTf.

6. A compound having structural Formula (VII):

wherein

X is alkyl, substituted alkyl, alkenyl, substituted alkenyl, heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substituted heteroalkenyl; and

R 7 is a leaving group selected from the group consisting of halo, —OMs, —OTs, and —OTf.

7. A process of preparing a compound having structural Formula (Ia):

comprising reacting a compound having structural Formula (VIII)

with R 8 —NH 2 , in the presence of an activating reagent;

wherein

Y is C1-C12 alkylene or C1-C12 alkenylene;

R 8 is C1-C12 alkyl; and

R 9 is hydrogen or C1-C12 alkyl.

8. The process of any of the claim 1 , 4 , and 5 , wherein the compound having structural Formula (I) is

9. A process of preparing a compound having structural Formula (Ib):

comprising reacting a compound having structural Formula (I)

with an alkali metal- or alkaline earth metal-based inorganic base,

wherein

M is a cation of alkali metal or alkaline earth metal;

X is alkyl, substituted alkyl, alkenyl, substituted alkenyl, heteroalkyl, substituted heteroalkyl, heteroalkenyl, or substituted heteroalkenyl;

n is 1, when M is a cation of alkali metal; and

n is 2, when M is a cation of alkaline earth metal.

10. The process of claim 9 , wherein

X is C1-C12 alkyl, C1-C12 heteroalkyl, C1-C12 alkenyl, C1-C12 heteroalkenyl, —Y—C(O)—OR 2 , or —Y—C(O)—NH—R 2 ;

Y is C1-C12 alkylene or C1-C12 alkenylene; and

each R 2 is independently hydrogen or C1-C12 alkyl.

11. The process of claim 9 , wherein the compound having structural Formula (Ib) is

12. A process of preparing a compound having structural Formula (Ia):

comprising

reacting a compound having structural Formula (IIc1)

with a hydroxide or alkoxide base in an aqueous solution at a temperature ranging from about 25 to about 95° C.,

wherein

Y is C1-C12 alkylene or C1-C12 alkenylene; and

R 8 is C1-C12 alkyl.

13. The process of claim 11 , wherein the compound having structural formula (Ia) is