title: Nucleophilic ring-opening in a carbohydrate nitrocyclopropane: a stereospecific approach to chiral isoalkyl structures.
abstract: Chemical reactions to open the cyclopropane ring in (1R)-1,2-dideoxy-3,4:5,6-di-O-isopropylidene-1,2-C-methylene-1-nitro-D-m annitol (1) were investigated. Catalytic hydrogenation over Pd-C produced the corresponding 1-amino compound, isolated as its N-acetyl derivative, but failed to cleave the ring. However, ring opening succeeded by nucleophilic addition of sodium thiophenoxide to 1, giving 1,2-dideoxy-3,4:5,6-di-O-isopropylidene-1-nitro-2-C- (phenylthio)methyl-D-mannitol. The latter reacted further with thiophenoxide to furnish phenyl 2-deoxy-3,4:5,6-di-O-isopropylidene-2-C-(phenylthio)methyl-D- mannothiohydroximate. Raney nickel converted both of these thio sugar derivatives into the same product, namely, 1-acetamido-1,2-dideoxy-3,4:5,6-di-O-isopropylidene-2-C-methyl-D-mannito l. The use of these transformations for the design of stereospecific syntheses of chiral isoalkyl structures is proposed.
mesh_terms: D000478:Alkylation; D003521:Cyclopropanes; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D008353:Mannitol / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D008358:Mannose; D009574:Nitro Compounds
chemical_list: D003521:Cyclopropanes; D007202:Indicators and Reagents; D009574:Nitro Compounds; C056093:1,2-dideoxy-3,4,5,6-di-O-isopropylidene-1,2-C-methylene-1-nitromannitol; D008353:Mannitol; C030797:cyclopropane; D008358:Mannose