Galactopyranose, 6-chloro-6-deoxy

The only recorded example using this method in the sugar series is the chlorination of l,2 3,4-di-0-isopropylidene-D-galactopyranose (73) which affords in addition to the expected 6-chloro-6-deoxy derivative 74a, a 5,6-unsaturated derivative 75 as well. These products were separated by silica gel column chromatography no yields were given. 

Chloro-6-deoxy-l,2 3,4-di-0-isopropylidene-a-D-galactopyranose has been obtained in 96% yield by treatment of l,2 3,4-di-0-isopropylidene-6-0-p-tolylsul-fonyl-a-D-galactopyranose with lithium chloride inN,N-dimethylformamide [see K. W. Buck and A. B. Foster,/. Chem. Soc., 2217 (1963)]. 

Kent and coworkers98 have reported that N-(2-chloro-l,l,2-tri-fluoroethyl)diethylamine (51) reacts with l,2 3,4-di-0-isopropylidene-a-D-galactopyranose (42) in N,N-dimethylformamide at 60°, in the presence of anhydrous potassium fluoride, to give a mixture from which 6-chloro-6-deoxy-1,2 3,4-di-O-isopropylidene-a-D-galactopyra-... 

In order to obviate the formation of a formic ester, the reaction of l,2 3,4-di-0-isopropylidene-a-D-galactopyranose (42) was performed in p-dioxane. The 6-chloro-6-deoxy derivative (45) was again obtained, but only in low yield the major product was assigned the novel structure of 6-0-(4,6-dichloro-l,3,5-triazin-2-yl)-l,2 3,4-di-0-isopropylidene-a-D-galactopyranose (54). 

Fig. 2.—Proton, Free-induction Decay Signal45 of a Solution of 6-Deoxy-1,2 3,4-di-O-isopropylidene-6-phthalimido-o-D-galactopyranose (54) (0.06 mg) in 4 1 (v/v) Chloro-form-d (Commercial, 100% )-Hexafluorobenzene (0.06 ml) Contained in a Microcell. [The f.i.d. signal was acquired in 419 sec by using the crossed-coil mode with hetero-nuclear, internal, field-frequency stabilization on fluorine-19, with 1,024 pulses at 90 MHz, tp 40 jusec, St 400 /jsec, and 1,024 datum points (for definitions, see text).]...

The reagent triphenylphosphine in refluxing carbon tetrachloride forms chlorodeoxy compounds from the corresponding hydroxy compounds without some of the complications encountered with other reagents (see Section 3). It has been used for the conversion of l,2 3,4-di-0-isopro-pylidene-a-D-galactopyranose into the corresponding 6-chloro-6-deoxy derivative. ... 

Fluoroformic and chloroformic esters of secondary alcohols may be decarboxylated, thermally or catalytically, to the corresponding fluoro-i or chloro-i i compound. Although 6-0-(chloroformyl)-1,2 3,4-di-O-iso-propylidene-a-D-galactopyranose is converted into 6-chloro-6-deoxy-l, 2 ... 

Tri-0-benzoyl-2-chloro-0 -D-xylopyranosyl chloride, the 4-chloroheptose derivative (2), 2-amino-2-deoxy-a-D-galactopyranosyl phosphate, 1,3,4,6-tetra-0-acetyl-2-(A -acetylacetamido)-2-deoxy- -D-galactopyranose, 2-acet-amido-lr/V - (L-aspart-4-oy l)-2- deoxy-jS-D-glucopyranosylamine, and iVn 3-D-gluco-pyranosyl procaine. ... 

Tetra-Ac 1,3,4,6-Tetra-0-acetyl-2-chloro-2-deoxy-p-D-galactopyranose [141510-63-6]... 

Chloro-6-deoxy-l, 2 3,4-di-0 -isopropylidene-a-D-galactopyranose, C-84 3-Chloro-3-deoxy-l,2 5,6-di-0-isopropylidene-a-D-glucofuranose, C-86 6-Chloro-6-deoxy-l,2 3,5-di-D-isopropylidene-a-D-glucofuranose, C-88... 

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