Thermal/hyperbaric heterocycloaddition of 1,4-dialkoxy-1,3-dienes: the de novo (E,Z) way to sugars.
1-(Z)-Alkoxy-4-(E)-methoxybutadiene derivatives have been reacted with ethylgyoxylate and diethyl ketomalonate under thermal or hyperbaric conditions. They provide, with a total regioselectivity and fair to total endoselectivities, the expected dihydropyranic cycloadducts. Three of those pseudo-glycals have been converted in a few classical steps (deprotection, reduction, and dihydroxylation) into (racemic) allose, mannose, and gullose derivatives. The order of these three steps has a direct influence on the efficiency of the transformation and determines the stereochemistry of the final sugar.
Bataille
Carole
C
Laboratoire des Fonctions Azotées et Oxygénées Complexes, UMR 6014 CNRS, IRCOF, Université de Rouen, 76821-Mont St. Aignan Cedex, France.
Bégin
Gautier
G
Guillam
Anne
A
Lemiègre
Loïc
L
Lys
Caroline
C
Maddaluno
Jacques
J
Toupet
Loïc
L
D000447:Aldehydes / Q000737:chemistry; D000466:Alkadienes / Q000737:chemistry; D002241:Carbohydrates / Q000138:chemical synthesis*; D011312:Pressure; D013237:Stereoisomerism; D013696:Temperature
D000447:Aldehydes; D000466:Alkadienes; D002241:Carbohydrates