Fluorous Protecting Groups

Fig. 4. Fluorous protecting group (Bnf) simultaneous function as protecting group and as fluorous tag.

Zhang, W. 2004. Fluorous protecting groups and tags. Handbook of Fluorous Chemistry. In J.A. Gladysz, D.P. Curran, and I.T. Horvath, eds., pp. 222-36. Whey-VCH Germany. 

T. Miura, K. Goto, H. Waragai, H. Matsumoto, Y. Hirose, M. Ohmae, H. Ishida, A. Satoh, and T. Inazu, Rapid oligosaccharide synthesis using a fluorous protective group, J. Org. Chem., 69 (2004) 5348-5353. 

Fluorous trialkyl silyl protecting groups have also been used to simplify the purification of complex reaction mixtures [5] (Scheme 3.16). Separation of the reaction products can be achieved by means of a simple three-phase extraction (aqueous/or-ganic/fluorous) instead of the usual chromatography. In this respect, the concept of using fluorous protecting groups has some parallels with the solid-phase-sup-ported chemistry which also was primarily developed to simplify multiple workup operations. 

A related strategy was used for synthesis of a more complex carbohydrate, the trisaccharide moiety of globotriaosyl ceramide (Gb3) [10b] (Scheme 3.19). In this reaction an acyl-based fluorous protecting group was used to facilitate the intermediate purification steps in a similar way as can be achieved by solid phase carbohydrate chemistry [12]. 

The use of fluorous catalysts is presented for general reactions (Section 3.3.1) and for enantioselective transformations (Section 3.3.2) fluorous analogues of traditional reagents are detailed in Section 3.3.3, followed in Section 3.3.4 by an account of the use of fluorous protecting groups. 

An assortment of light fluorous protecting groups are commercially available ( CBz , diisopropyl silane, Marshall ester ) or can be readily... 

Synthesis of a tetrasaccharide using a fluorous protective group... 

Fluorous-Protecting Groups and Tags Amenable to Fluorous Solid-Phase Extraction I 225... 

Scheme 8.2 Fluorous-protecting groups for amine and phosphate used in oligosaccharide synthesis.

Scheme S.4 Several fluorous-protecting groups have been reported, which could potentially be readily applied to carbohydrate synthesis.

Scheme 8.5 Temporary fluorous-protecting groups used in can. .

Double-Tagging Carbohydrates with Fluorous-Protecting Groups I 231... 

With the advent of automation methods amenable to the use of fluorous-protecting group tags, explorations of the scope and limitations of fluorous-protecting groups... 

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