Extension of the Nef reaction to C-glycosylnitromethanes.
Acid-catalysed methanolysis of 3,4,5,6-tetra-O-acetyl-1,2-dideoxy-l-arabino-hex-1-enitol proceeds via a cascade set of consecutive reactions resulting in its regiospecific conversion to a mixture of alpha- and beta-C-L-arabinofuranosylmethanal dimethyl acetals and a mixed internal methyl acetal. Structures of the final products of the overall process provide unique evidence that a kinetically controlled, five-membered-ring closure precedes a six-membered-ring closure in reversible systems capable of giving both five-membered and six-membered all-sp3-atom rings. Determination of the reaction intermediate enabled extension of the Nef reaction to C-glycosylnitromethanes. Protonated aci-nitro forms of C-glycosylnitromethanes that are resistant to the Nef reaction in aqueous acidic media undergo a modified Nef reaction in acidified methanol, and the corresponding C-glycosylmethanal dimethyl acetals with alpha-L-arabinopyranosyl, beta-D-glucopyranosyl, beta-D-galactopyranosyl, beta-D-mannopyranosyl and beta-L-rhamnopyranosyl configurations were obtained in moderate yields.
Petrusová
Mária
M
Institute of Chemistry, Slovak Academy of Sciences, SK-84538 Bratislava, Slovakia.
Vojtech
Michal
M
Pribulová
Bozena
B
Lattová
Erika
E
Matulová
Mária
M
Poláková
Monika
M
BeMiller
James N
JN
Kren
Vladimír
V
Petrus
Ladislav
L
D007700:Kinetics; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D008956:Models, Chemical; D015394:Molecular Structure; D009005:Monosaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D009595:Nitroparaffins / Q000737:chemistry*
D009005:Monosaccharides; D009595:Nitroparaffins; D008697:Methane; C008640:nitromethane