PROCESS FOR PREPARATION OF ALDONIC ACIDS AND DERIVATIVES THEREOF
A process for the preparation of L-gluconic acid or a salt thereof, comprises treating an aqueous solution of 6-bromo-6-deoxy-2,3-anhydro-D-manno-1,4-lactone with a base at a pH of at least 12 and at a temperature of 45 to 55° C. to obtain an aqueous solution of L-gluconic acid.
1 . A process for preparing a compound, comprising:
reacting 2,6-dibromo-2,6-dideoxy-D-mannono-1,4-lactone with a Lewis base and a catalytic amount of water, to form 6-bromo-6-deoxy-2,3-anhydro-D-manno-1,4-lactone.
2 . The process of claim 1 , wherein the reacting is carried out in a solvent comprising a ketone.
3 . The process of claim 1 , wherein the catalytic amount of water is 0.05 to 2% by weight of a solvent in which the 6-bromo-6-deoxy-2,3-anhydro-D-manno-1,4-lactone is formed.
4 . The process of claim 1 , wherein the catalytic amount of water is 0.75 to 0.8% by weight of a solvent in which the 6-bromo-6-deoxy-2,3-anhydro-D-manno-1,4-lactone is formed.
5 . The process of claim 1 , wherein the Lewis base comprises at least one member selected from the group consisting of fluorides and carbonates.
6 . The process of claim 1 , wherein the Lewis base comprises potassium fluoride and potassium carbonate.
7 . The process of claim 1 , wherein the reacting is carried out at a temperature of 20 to 45° C.
8 . The process of claim 2 , wherein:
the catalytic amount of water is 0.05 to 2% by weight of the solvent,
the Lewis base comprises at least one member selected from the group consisting of fluorides and carbonates, and
the reacting is carried out at a temperature of 20 to 45° C.
9 . The process of claim 1 , further comprising forming L-glucose from the 6-bromo-6-deoxy-2,3-anhydro-D-manno-1,4-lactone.
10 . The process of claim 8 , further comprising forming L-glucose from the 6-bromo-6-deoxy-2,3-anhydro-D-manno-1,4-lactone.
11 . A process for preparing a compound, comprising:
reacting a bromohydrin with a Lewis base and a catalytic amount of water, to form an epoxide.
12 . The process of claim 11 , wherein the bromohydrin is α-lactone.
13 . The process of claim 11 , wherein the bromohydrin is an α-bromohydrin lactone.
14 . The process of claim 11 , wherein the bromohydrin is an α-bromohydrin aldonolactone.
15 . The process of claim 11 , wherein the reacting is carried out in a solvent comprising a ketone.
16 . The process of claim 11 , wherein the catalytic amount of water is 0.05 to 2% by weight of a solvent in which the epoxide is formed.
17 . The process of claim 11 , wherein the Lewis base comprises at least one member selected from the group consisting of fluorides and carbonates.
18 . The process of claim 11 , wherein the reacting is carried out at a temperature of 20 to 45° C.
19 - 25 . (canceled)
26 . A process for preparing a compound, comprising:
reacting 6-bromo-6-deoxy-2,3-anhydro-D-manno-1,4-lactone with a base at a pH of at least 12 and at a temperature of 45 to 55° C., to form L-gluconic acid or a salt thereof.
27 - 30 . (canceled)
31 . A process for preparing a compound, comprising:
reacting D-glucono-1,5-lactone or a salt thereof with a hydrogen halide at a temperature of from 40 to 60° C., to form a reaction mixture; and
adding methanol to the reaction mixture, to form 2,6-dibromo-2,6-dideoxy-D-mannono-1,4-lactone.
32 - 37 . (canceled)