Simultaneous Application of Arylmethylene Acetal and Butane Diacetal Groups for Protection of Hexopyranosides: Synthesis and Chemoselective Ring-Opening Reactions

Mihály Herczeg, Fruzsina Demeter, Erika Mezo, Máté Pap, A. Borbás

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The reductive cleavage of 4,6-O-arylmethylene acetals of hexopyranosides is an effective method for the regioselective formation of a benzyl-type ether at either the C-4 or the C-6 hydroxyl group. The compatibility of this method with Ley's butane diacetal (BDA) protection was studied. 4,6-O-(2-Naphthyl)methylene, benzylidene, and p-methoxybenzylidene acetals were introduced to 2,3-O-BDA-protected gluco- and galactosides, and the bis-acetalated products were subjected to reductive acetal openings with different reagents. LiAlH4-AlCl3 reduced the 4,6-acetals with complete chemo- and regioselectivity to give the corresponding 4-O-ethers. The use of Et3SiH-BF3·Et2O led to a mixture of differently reduced products, because transformation of the 4,6-acetal into the related 6-O-ether and reduction of the BDA system into a butane-2,3-diyl group took place competitively. BH3·NMe3-AlCl3 selectively cleaved the 4,6-acetal ring to give the 6-O-ethers as the major or exclusive products.

Original languageEnglish
Pages (from-to)5730-5741
Number of pages12
JournalEuropean Journal of Organic Chemistry
Volume2015
Issue number26
DOIs
Publication statusPublished - Sep 1 2015

Fingerprint

acetals
Acetals
butanes
rings
ethers
synthesis
Ethers
Ether
products
Galactosides
Regioselectivity
methylene
Hydroxyl Radical
compatibility
reagents
butane
cleavage

Keywords

  • Acetals
  • Carbohydrates
  • Chemoselectivity
  • Protecting groups
  • Reduction
  • Ring opening

ASJC Scopus subject areas

  • Organic Chemistry
  • Physical and Theoretical Chemistry

Cite this

Simultaneous Application of Arylmethylene Acetal and Butane Diacetal Groups for Protection of Hexopyranosides : Synthesis and Chemoselective Ring-Opening Reactions. / Herczeg, Mihály; Demeter, Fruzsina; Mezo, Erika; Pap, Máté; Borbás, A.

In: European Journal of Organic Chemistry, Vol. 2015, No. 26, 01.09.2015, p. 5730-5741.

Research output: Contribution to journalArticle

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