Regioselective Synthesis of Phosphonylated Sugars from Reactions of Glycals with Diphenylphosphenium Cation
摘要:
Reaction of methyl 4,6-di-O-acetyl-2,3-dideoxy-D-erythro-hex-2-enopyranoside 1 with two equivalents of diphertylphosphenium cation at 0degreesC gave the 1-phosphonylated 2-enopyranos ides 3alpha and 3beta as major products. Similarly, reaction of diphenylphosphenium cation with tri-O-acetylglycal afforded the same products in a similar ratio. In contrast, a reaction with tri-O-benzylglucal at reflux temperature of dichloromethane afforded the 3-phosphonylated sugar 13 as a major product. These reactions may proceed via stable allyl cations.
Regioselective Synthesis of Phosphonylated Sugars from Reactions of Glycals with Diphenylphosphenium Cation
摘要:
Reaction of methyl 4,6-di-O-acetyl-2,3-dideoxy-D-erythro-hex-2-enopyranoside 1 with two equivalents of diphertylphosphenium cation at 0degreesC gave the 1-phosphonylated 2-enopyranos ides 3alpha and 3beta as major products. Similarly, reaction of diphenylphosphenium cation with tri-O-acetylglycal afforded the same products in a similar ratio. In contrast, a reaction with tri-O-benzylglucal at reflux temperature of dichloromethane afforded the 3-phosphonylated sugar 13 as a major product. These reactions may proceed via stable allyl cations.
Reaction of methyl 4,6-di-O-acetyl-2,3-dideoxy-D-erythro-hex-2-enopyranoside 1 with two equivalents of diphertylphosphenium cation at 0degreesC gave the 1-phosphonylated 2-enopyranos ides 3alpha and 3beta as major products. Similarly, reaction of diphenylphosphenium cation with tri-O-acetylglycal afforded the same products in a similar ratio. In contrast, a reaction with tri-O-benzylglucal at reflux temperature of dichloromethane afforded the 3-phosphonylated sugar 13 as a major product. These reactions may proceed via stable allyl cations.