D-Glucal tri-0-acetyl

All derivatives used were prepared by essentially standard literature procedures and had physical constants in accord with previously reported values. Furthermore, the P.M.R. spectra were in each case consistent with the assigned structures. All solutions were concentrated under reduced pressure and m.p. s are uncorrected. (I) 2-Deoxy-D-arafczno-hexopyranose was a commercial sample from Pfanstiehl Lab. Inc., Waukegan, Illinois and was used without further purification. (II) 3, 4, 6-Tri-O-acetyl-D-glucal (1) was a commercial sample from Aldrich Chem. Co., Milwaukee, Wisconsin and was purified by distillation and recrystallized three times from aqueous ethanol. (Ill) 1, 3, 4, 6-tetra-0-acetyl-2-deoxy-a-D-arahino-hexopyranose (4) was prepared by the method of Bonner (11) while the corresponding / -anomer (5) was synthesized following the procedure of Overend, Stacey, and Stanek (47). (IV) 5, 6-Dideoxy-1, 2-0-isopropylidene-a-D-xj/io-hex-5-enofuranose (20) was provided by A. Rosenthal and G. Khan of this Department. 

Introduction of F2 into 3,4,6-tri-O-acetyl-D-glucal (61) in CCI3F (Freon 11) at —78° in a manner used for the non-labeled compound (so-called cold synthesis) gave a 4 1 mixture of 3,4,6-tri-0-acetyl-2-deoxy-2-[ F]fluoro-a-D-gluco- (574) and ) -D-manno-pyranosyl fluorides (575),... 

An approach to 2-deoxy-2-(thiocyanato)-D-glucopyranose derivatives has been reported by Igarashi and Honma.37 This reaction proceeds in the presence of acetic acid and acetic anhydride by addition of thiocyanogen to 3,4,6-tri-O-acetyl-D-glucal (20), with the formation of a mixture of isomeric thiocyanates (274 and 275) and isothiocyanate 21 (3% yield), as well as 3,4,6-tri-0-acetyl-2-(thiocyanato)-D-glucal (276). 

An isolated example of the use of x-ray diflraction analysis is provided by the work of Camerman and coworkers. Hydroformyl-ation of 3,4,6-tri-O-acetyl-D-glucal gave 4,5,7-tri-0-acetyl-2,6-anhydro-3-deoxy-D-gIuco- and -D-manno-heptitols, which were converted into the corresponding 1-p-bromobenzenesulfonates. One of these sulfonates was shown hy x-ray analysis to have the CJ(d) conformation in which all of the substituents are oriented equatorially hence, this sulfonate was the D-gluco isomer. 

Tri-O-acetyl-D-glucal has been converted into 3,4,6-tri-0-acetyl-2-deoxy-2-fluoro-a-D-glucopyranosyl fluoride (35%) and the corresponding -o-manno-difluoride (26%) by reaction with fluorine diluted with argon at — 78°C. This method could be used to introduce a F-Iabel into 2-deoxy-2-fluoro-D-glucose, which is readily obtained by hydrolysis of the a-D- /uco-difluoride. The reactions shown in Scheme 26 have been used to synthesize 2-deoxy-2-fluoro-D-allose a... 

In 2009, Balamurugan et al. discovered that AuCls might efficiently catalyze the Perrier reaction of 3,4,6-tri-O-acetyl-D-glucal 5 with a range of 0-, S-, and C-nucleophiles to afford 2,3-unsaturated 0-, S-, and C-glycosyl compounds 6, respectively. Moderate to good a-selectivity was observed (Scheme 3). ... 

Unsaturated sugars are useful synthetic intermediates (11). The most commonly used are the so-called glycals (1,5- or 1,4-anhydroalditol-l-enes). In the presence of a Lewis-acid catalyst, 3,4,6-tri-0-acetyl-l,5-anhydro-2-deoxy-D-arabinohex-l-enitol [2873-29-2] commonly called D-glucal triacetate, adds nucleophiles in both kineticaHy controlled and thermodynamically controlled (soft bases predominately at C-3 and hard bases primarily at C-1) reactions (11,13). 

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