Single Diastereomers of Polyhydroxylated 9-Oxa-1-azabicyclo[4.2.1]nonanes from Intramolecular 1,3-Dipolar Cycloaddition of ω-Unsaturated Nitrones

• Published in: Journal of organic chemistry 2006-10, Vol.71 (22), p.8669-8672
• Main Authors: Pádár, Petra, Bokros, Attila, Paragi, Gábor, Forgó, Péter, Kele, Zoltán, Howarth, Nicola M, Kovács, Lajos
• Format: Article
• Language: English
• Subjects: Alkanes - chemical synthesis; Alkanes - chemistry; Carbohydrates with 4, 5, 6, ... C atoms, dissacharides and oligosaccharides; Carbohydrates. Nucleosides and nucleotides; Chemistry; Cyclization; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with o, s, se, te hetero atom and condensed derivatives; Heterocyclic compounds with several n hetero atoms in the same ring, in separated rings or in fused rings; Hydroxylation; Molecular Structure; Nitrogen Oxides - chemistry; Organic chemistry; Preparations and properties; Stereoisomerism
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo061503b

8-Benzyloxymethyl-3,4,5-tribenzoyloxy-9-oxa-1-azabicyclo[4.2.1]nonane has been prepared as the single diastereoisomer 8 from an intramolecular 1,3-dipolar cycloaddition involving 2-(benzyloxy)acetaldehyde and ω-unsaturated hydroxylamine 7 derived from methyl α-d-glucopyranoside. The analogous 8-methoxycarbonyl 9-oxa-1-azabicyclo[4.2.1]nonane was afforded in a similar manner, from methyl d-galactopyranoside and methyl glyoxylate, as a 3:1 mixture of diastereoisomers 15 and 16. When conducted in achiral ionic liquid 17 this ratio increased to 8:1, and in chiral ionic liquid 18, compound 15 was formed exclusively.