Stereocontrolled synthesis of C-glycosides: further studies on the organolithium reagents derived from 2-deoxy-D-glucose and D-glucose.
The addition of alpha- and beta-2-deoxy-D-glucopyranosyl lithium reagents i and ii to prochiral aldehydes is a syn-selective process, synthetically useful only with the alpha-lithio reagent i (syn:anti selectivity of approximately 10:1 with saturated aldehydes). This has been demonstrated by using propionaldehyde and converting the syn-isomers of both series to an easily identified acyclic meso-chain (alpha-series) or a C2 symmetric acyclic chain (beta-series). The preparation of alpha- and beta-D-glucopyranosyl dilithio reagents 26 and 27 is possible but a notable decrease in efficiency and facial selectivity is observed in coupling reactions with model aldehydes.
Lesimple
P
P
Université d'Orléans, Laboratoire de Biochimie Structurale associé au CNRS, Orléans, France.
Beau
J M
JM
D000447:Aldehydes / Q000378:metabolism; D003847:Deoxyglucose / Q000737:chemistry* / Q000378:metabolism; D005947:Glucose / Q000737:chemistry* / Q000378:metabolism; D006027:Glycosides / Q000138:chemical synthesis*; D007202:Indicators and Reagents / Q000138:chemical synthesis; D018020:Lithium Compounds / Q000138:chemical synthesis*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D013237:Stereoisomerism
D000447:Aldehydes; D006027:Glycosides; D007202:Indicators and Reagents; D018020:Lithium Compounds; D003847:Deoxyglucose; D005947:Glucose