Mitsunobu glycosidation

If it is assumed that the Mitsunobu glycosidation reaction described above proceeds through an SN2-type process with inversion of configuration at the anomeric position, then it follows that the desired / -glycoside can be formed selectively if pure a-lactol 17 is used in the reaction. Unfortunately, the /Mactol isomer of 17 is thermodynamically more stable than the a-diastereoisomer and is formed almost exclusively if the system is allowed to fully equilibrate. In the protic medium used for the Luche reduction, a signifi-... 

Michael addition/elimination 256 Mitsunobu glycosidation 543 ff. Mitsunobu reaction 259, 5291,... 

The glycosylation based on the Mitsunobu reaction has been most commonly directed to the synthesis of O-aryl glycosides, a structural motif found in a variety of natural products [80-82], Early work by Grynkiewicz [83,84], among others [85-87], established the viability of triphenylphosphine and diethylazodicarboxylate to promote the glycosylation of phenol acceptors at ambient temperature. More recently, Roush and coworkers have discovered that the glycosylation performed well in the... 

Weinges, K. Haremsa, S. Maurer, W., The Mitsunobu Reaction on Methyl Glycosides as Alcohol Component. Carbohydr. Res. 1987, 164, 453-458. 

Fluoroalkyl Glycosides (RFn-(CH2)2-n-0-sugar) and Perfluor-oalkylidene Acetals Derived from Sugars The very low nucleophilicity of fluoroalcohols makes it difficult to substitute of a hydroxyl (anomeric or not). ° This is the reason why this type of ether is not very common. Such ethers have only been isolated in very small quantities in solvolysis reactions, or in carben insertions, performed in fluorous alcohols.Preparation of these ethers has been solved by means of the Mitsunobu reaction. This reaction is known to be dependent on the pA a of the acceptor of the glycosyl the acidity of fluorous alcohols allows a much easier deprotonation than with non fluorinated alcohols." ... 

K. Weinges, S. Haremsa, and W. Maurer, The Mitsunobu reaction on methyl glycosides as alcohol component, Carbohydr. Res. 164 453 (1987). 

As the Mitsunobu reaction requires weakly acidic nucleophiles, and since phenols have the necessary acidity, aryl glycosides [409-411] have been prepared this way. However, alcohols are... 

The 2-oxabicyclo[3.1.0]hexane nucleoside 166 was obtained via a Simmons-Smith type cyclopropanation reaction of intermediate 164, followed by glycosidation with several natural heterocyclic bases <05JOC6891 05NNNA383>. A restricted version of puromycin built on a bicyclo[3.1.0]hexane template was synthesized by Choi via Mitsunobu coupling of a 3-azido-substituted carbocyclic moiety with 6-chloropurine to give compound 167 <02OL589>. 

Aryl 2-deoxy-p-D-glycosides.1 These glycosides (4) can be prepared in high /3-selectivity by Mitsunobu coupling of phenols with 2a-(thiophenyl)- or 2a-(sclcno-phenyl)-a-D-pyranosnes 2, prepared by reaction of C6HsSC1 or Cf,HMitsunobu conditions provides mainly fi-... 

Inversion of configuration (cf Epimerization) of alcohols (Mitsunobu reaction), 160-161, 286 of ally lie acetates with Pd, 27, 164 of allylpalladium with d-synthons, 27, 264 of alkyl halides or sulfonates by 1,3-dithiane anions, 22 by organylcuprates, 36 by tetracarbonylferrate<2 -X 46-47 in triorganylborane rearr., 37-38 of glycosides with free 2-OH by DAST, 272 of glycosyl halides, 271 of oxiranes by 1-alkync anions, 64, 204 by enolate type anions, 63-64 by internal alcoholate addition, 265 Inversion-esterification of alcohols, 160-161, 286 Inverted DNA , 345-346 Iodide, hydrogen porphyrin synthesis with, 255 Iodine = diiodine (Ij) ... 

Viso A, Poopeiko N, Castilldn S (2000) Stereoselective synthesis of nucleosides from 1-thio and 1-seleno glycosides through consecutive 1,2-migration and glycosylation under Mitsunobu conditions. Tetrahedron Lett 41 407-411... 

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