Mukaiyama glycosyl fluoride

The preparation of glycosyl fluorides is described next. Aiming to have a convenient glycosyl donor convertible into 1,2-CM-furanosides, Mukaiyama and coworkers prepared 2,3,5-tri-O-benzyl-yS-D-ribofuranosyl fluoride (36y3) by treatment of a protected D-ribofuranose (35) with 2-fluoro-1 -meth-ylpyridinium tosylate (FMPTs) the total yield was raised by anomerizing the simultaneously produced a-1-fluoride (36a, 7, p 66, 72.f 24 Hz) to 36 (7, F 63.5 Hz, 72,F very small ) by treatment with BF3-OEt2. 

Glycosylations utilizing the aforedescribed glycosyl fluorides are described next. In 1981, Mukaiyama and coworkers attempted to prepare 1,2-cw-glycosides by utilizing the relatively stable (as compared with other glycosyl halides) 2,3,4,6-tetra-0-benzyl-)8-D-glucopyranosyl fluoride (47)5)... 

Jona, H, Mandai, H, Chavasiri, W, Takeuchi, K, Mukaiyama, T, Protic acid catalyzed stereoselective glycosylation using glycosyl fluorides. Bull. Chem. Soc. Jpn., 75, 291-309, 2002. 

Mukaiyama, T, Jona, H, Takeuchi, K, Trifluoromethanesulfonic acid (TfOH)-catalyzed stereoselective glycosylation using glycosyl fluoride, Chem. Lett., 696-691, 2000. 

Mukaiyama, T, Takeuchi, K, Jona, H, Maeshima, H, Saitoh, T, A catalytic and stereoselective glycosylation with (3-glycosyl fluorides, Helv. Chim. Acta, 83, 1901-1918, 2000. 

Yanagisawa, M, Mukaiyama, T, Catalytic and stereoselective glycosylation with glycosyl fluoride using active carbocationic species paired with tetrakis(pentafluorophenyl)borate or trifluorometha-nesulfonate, Chem. Lett., 224-225, 2001. 

Mukaiyama, T, Maeshima, H, Jona, H, Catalytic and stereoselective glycosylation with disarmed glycosyl fluoride by using a combination of stannous(II) chloride (SnCl2) and silver tetrakis(penta-fluorophenyl)borate [AgB(C6F5)4] as a catalyst, Chem. Lett, 388-389, 2001. 

Within the present article, a few selected examples are provided ofboth classical and more recent glycosylation methods applied to the synthesis of sLcL sLe", or of sulfated Lewis determinants. Recent procedures involve the use of glycal donors as developed by Danishefsky and his associates, of glycosyl fluorides according to Mukaiyama and Nicolaou, of sulfoxide donors as reported by Kahne, and enzyme-catalyzed oligosaccharide syntheses as developed by the schools of Whitesides, Wong, and Paulson. ... 

---