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Phenylsulfones, anomeric

Anomeric triphenylphosphonium salts have been used as well as phenylsul-fides,but in the latter case extra stabilization is necessary (see below). Anomeric nitrosugars, which have been extensively studied in C-glycosylation reactions by Vasella, will be covered in Sect. 2.2.1 and ester enolates derived from 3-deoxy-2-ketoulosonic acids (sialic acid and KDO derivatives), which bear a structural similarity to 2-deoxy pyranosides, will be covered in Sect. 4.4. Deprotonation of anomeric phenylsulfones has been discussed in Sect. 2.1.1 and additional transformations on closely related compounds are presented in Scheme 14 [20]. Alkylation of phenylsulfone 54 with epoxide 55 provides adduct 56 which eliminates benzenesulfinic acid at room temperature to give the C(l)-alkylated glycal 57 a similar elimination is also observed with adducts derived from... [Pg.10]

Beau and Sinay have developed an efficient synthesis of 2-deoxy-jS-glycosides based on anomeric phenylsulfone alkylation followed by in situ reductive lithiation with lithium naphthalenide (LN). The -C-glycoside product is established after protic quench of the intermediate axial alkyllithium (Scheme 12) [20]. [Pg.838]

Scheme 12. Alkylation/reductive lithiation of an anomeric phenylsulfone... Scheme 12. Alkylation/reductive lithiation of an anomeric phenylsulfone...

See other pages where Phenylsulfones, anomeric is mentioned: [Pg.22]    [Pg.22]    [Pg.105]    [Pg.144]    [Pg.146]    [Pg.146]    [Pg.336]   
See also in sourсe #XX -- [ Pg.340 ]




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