Mechanistic studies on the stereoselective formation of glycosyl iodides

First characterization of β-D-glycosyliodides

Jacquelyn Gervay-Hague, Truc N. Nguyen, Michael J. Hadd

Research output: Contribution to journalArticle

66 Citations (Scopus)

Abstract

Treatment of glycosyl acetates with one equivalent of iodotrimethylsilane at low temperature results in the quantitative formation of glycosyl iodides. Carbohydrates that possess a participating group at the C-2 position initially form β-D-glycosyl iodides, which quickly equilibrate to the α-iodo anomers. The β anomer of peracetylated glucose reacts faster than the α anomer, presumably because the C-2 acetate can assist in displacing the silylated anomeric acetate. In contrast, the α anomer reacts faster than the β anomer in substrates lacking a participating group at C-2. For example, activation of 1-O-acetyl-2,3,4,6-tetra-O-benzyl-α-D-glucopyranose leads to formation of the β iodide, while the corresponding β acetate produces the α iodide. Although the β iodides quickly equilibrate to the α anomers, they can be prepared in sizable quantities at low temperatures where equilibration is slow. This report describes the first stereoselective formation and characterization of β-D-glycosyl iodides.

Original languageEnglish (US)
Pages (from-to)119-125
Number of pages7
JournalCarbohydrate Research
Volume300
Issue number2
DOIs
StatePublished - May 12 1997
Externally publishedYes

Fingerprint

Iodides
Acetates
Temperature
Chemical activation
Carbohydrates
Glucose
Substrates

Keywords

  • β-D-Glycosyl iodides
  • Glycosyl iodides
  • NMR characterization

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Organic Chemistry

Cite this

Mechanistic studies on the stereoselective formation of glycosyl iodides : First characterization of β-D-glycosyliodides. / Gervay-Hague, Jacquelyn; Nguyen, Truc N.; Hadd, Michael J.

In: Carbohydrate Research, Vol. 300, No. 2, 12.05.1997, p. 119-125.

Research output: Contribution to journalArticle

@article{97e8c39f8f964228bbff2412d153deed,
title = "Mechanistic studies on the stereoselective formation of glycosyl iodides: First characterization of β-D-glycosyliodides",
abstract = "Treatment of glycosyl acetates with one equivalent of iodotrimethylsilane at low temperature results in the quantitative formation of glycosyl iodides. Carbohydrates that possess a participating group at the C-2 position initially form β-D-glycosyl iodides, which quickly equilibrate to the α-iodo anomers. The β anomer of peracetylated glucose reacts faster than the α anomer, presumably because the C-2 acetate can assist in displacing the silylated anomeric acetate. In contrast, the α anomer reacts faster than the β anomer in substrates lacking a participating group at C-2. For example, activation of 1-O-acetyl-2,3,4,6-tetra-O-benzyl-α-D-glucopyranose leads to formation of the β iodide, while the corresponding β acetate produces the α iodide. Although the β iodides quickly equilibrate to the α anomers, they can be prepared in sizable quantities at low temperatures where equilibration is slow. This report describes the first stereoselective formation and characterization of β-D-glycosyl iodides.",
keywords = "β-D-Glycosyl iodides, Glycosyl iodides, NMR characterization",
author = "Jacquelyn Gervay-Hague and Nguyen, {Truc N.} and Hadd, {Michael J.}",
year = "1997",
month = "5",
day = "12",
doi = "10.1016/S0008-6215(96)00321-7",
language = "English (US)",
volume = "300",
pages = "119--125",
journal = "Carbohydrate Research",
issn = "0008-6215",
publisher = "Elsevier BV",
number = "2",

}

TY - JOUR

T1 - Mechanistic studies on the stereoselective formation of glycosyl iodides

T2 - First characterization of β-D-glycosyliodides

AU - Gervay-Hague, Jacquelyn

AU - Nguyen, Truc N.

AU - Hadd, Michael J.

PY - 1997/5/12

Y1 - 1997/5/12

N2 - Treatment of glycosyl acetates with one equivalent of iodotrimethylsilane at low temperature results in the quantitative formation of glycosyl iodides. Carbohydrates that possess a participating group at the C-2 position initially form β-D-glycosyl iodides, which quickly equilibrate to the α-iodo anomers. The β anomer of peracetylated glucose reacts faster than the α anomer, presumably because the C-2 acetate can assist in displacing the silylated anomeric acetate. In contrast, the α anomer reacts faster than the β anomer in substrates lacking a participating group at C-2. For example, activation of 1-O-acetyl-2,3,4,6-tetra-O-benzyl-α-D-glucopyranose leads to formation of the β iodide, while the corresponding β acetate produces the α iodide. Although the β iodides quickly equilibrate to the α anomers, they can be prepared in sizable quantities at low temperatures where equilibration is slow. This report describes the first stereoselective formation and characterization of β-D-glycosyl iodides.

AB - Treatment of glycosyl acetates with one equivalent of iodotrimethylsilane at low temperature results in the quantitative formation of glycosyl iodides. Carbohydrates that possess a participating group at the C-2 position initially form β-D-glycosyl iodides, which quickly equilibrate to the α-iodo anomers. The β anomer of peracetylated glucose reacts faster than the α anomer, presumably because the C-2 acetate can assist in displacing the silylated anomeric acetate. In contrast, the α anomer reacts faster than the β anomer in substrates lacking a participating group at C-2. For example, activation of 1-O-acetyl-2,3,4,6-tetra-O-benzyl-α-D-glucopyranose leads to formation of the β iodide, while the corresponding β acetate produces the α iodide. Although the β iodides quickly equilibrate to the α anomers, they can be prepared in sizable quantities at low temperatures where equilibration is slow. This report describes the first stereoselective formation and characterization of β-D-glycosyl iodides.

KW - β-D-Glycosyl iodides

KW - Glycosyl iodides

KW - NMR characterization

UR - http://www.scopus.com/inward/record.url?scp=0030914044&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030914044&partnerID=8YFLogxK

U2 - 10.1016/S0008-6215(96)00321-7

DO - 10.1016/S0008-6215(96)00321-7

M3 - Article

VL - 300

SP - 119

EP - 125

JO - Carbohydrate Research

JF - Carbohydrate Research

SN - 0008-6215

IS - 2

ER -