Process for the preparation of protected mono-sugar and oligo-sugar halides

Claim 2

A process for the preparation of a protected sugar halide or halogenated sugar derivative having an anomeric halogen atom by halogenating the anomeric hydroxy group, which comprises reacting one equivalent of a protected sugar or a protected sugar derivative, wherein said sugar derivative is a deoxy-sugar, amino-sugar, thio-sugar, sugar acid or an ester of a sugar acid having an anomeric hydroxyl group, with an equivalent of a secondary α-haloenamine in an inert solvent at a temperature between -20° and 80° C.

Claim 3

A process according to claim 1, wherein the solvent used is a halogenated aliphatic hydrocarbon, an aromatic hydrocarbon or an aliphatic ether.

Claim 4

A process according to claim 1, wherein the process is conducted in the presence of 1 to 3 equivalents of the α-haloenamine.

Claim 5

A process according to claim 1, which is carried out under an atmosphere of a protective gas.

Claim 6

A process according to claim 1, wherein the α-haloenamine has the formula I ##STR2## in which each of R 1 and R 2 independently of one another is linear or branched C 1 -C 12 alkyl, C 4 -C 7 cyclalkyl, C 1 -C 12 alkyl-C 4 -C 7 cycloalkyl, C 4 -C 7 cycloalkylmethyl, C 1 -C 12 alkyl-C 4 -C 7 cycloalkylmethyl, phenyl, C 1 -C 12 alkylphenyl, benzyl or C 1 -C 12 alkylbenzyl, or each of R 1 and R 2 together is tetramethylene, pentamethylene or hexamethylene; R 3 and R 4 independently of one another are linear or branched C 1 -C 12 alkyl, C 4 -C 7 cyclalkyl, C 1 -C 12 alkyl-C 4-C 7 cycloalkyl, C 4 -C 7 cycloalkylmethyl, C 1 -C 12 alkyl-C 4 -C 7 cycloalkylmethyl, phenyl or benzyl, or R 3 and R 4 together are tetramethylene, pentamethylene or 3-oxa-1,5-pentylene; and X is halogen.

Claim 7

A process according to claim 5, wherein R 1 and R 2 independently of one another are C 1 -C 6 alkyl.

Claim 8

A process according to claim 6, wherein R 1 and R 2 are each methyl.

Claim 9

A process according to claim 5, wherein R 3 and R 4 independently of one another are C 1 -C 6 alkyl.

Claim 10

A process according to claim 8, wherein R 3 and R 4 are each C 1 -C 4 alkyl.

Claim 11

A process according to claim 8, wherein R 3 and R 4 are identical and are methyl, ethyl, n-propyl or isopropyl.

Claim 12

A process according to claim 1, wherein the protected sugar or sugar derivative is a monosaccharide or oligosaccharide or a monosaccharide or oligosaccharide derivative.

Claim 13

A process according to claim 11, wherein the protected monosaccharide or oligosaccharide is an aldose or ketose having an anomeric hydroxyl group.

Claim 14

A process according to claim 11, wherein the protected monosaccharide or oligosaccharide is an aldopyranose aldohexose, aldofuranose, ketopyranose or ketofuranose having an anomeric hydroxyl group.

Claim 15

A process according to claim 13, wherein the aldopyranose is D-ribose, D-arabinose, D-xylose, or D-lyxose; the aldohexose is D-allose, D-altrose, D-glucose, D-mannose, D-gulose, D-idose, D-galactose or D-talose; and the ketofuranose is D-psicose, D-fructose, D-sorbose or D-tagatose; the hydroxyl groups thereof, apart from the anomeric hydroxyl group, being protected.

Claim 16

A process according to claim 1, wherein the hydroxyl groups of the sugar or sugar derivative, apart from the anomeric hydroxyl group, are protected by C 1 -C 8 alkyl, trialkylsilyl having 3 to 20 C atoms, C 7 -C 12 aralkyl, C 1 -C 12 alkylidene, benzylidene, C 2 -C 12 acyl or R 5 -SO 2 -, R 5 being C 1 -C 12 alkyl, C 5 cycloalkyl, C 6 cycloalkyl, phenyl, benzyl, C 1 -C 12 alkylphenyl or C 1 -C 12 alkylbenzyl.

Claim 17

A process according to claim 1, wherein the reaction is begun at a temperature between -20° and 20° C. and allowed to proceed to complete conversion at an elevated temperature of up to 80° C.

Claim 18

A process according to claim 16, wherein the reaction is begun at a temperature of about 0° C. and allowed to proceed to complete conversion at an elevated temperature of up to 80° C.