Chiral ionic liquids derived from isosorbide: synthesis, properties and applications in asymmetric synthesis
作者:Olivier Nguyen Van Buu、Audrey Aupoix、Nhung Doan Thi Hong、Giang Vo-Thanh
DOI:10.1039/b902956g
日期:——
A novel class of chiral ammonium and imidazolium-based ionic liquids has been designed and synthesized using isosorbide as a biorenewable substrate. These chiral ionic liquids were found to catalyze the aza Diels–Alder reaction to give good yields and moderate diastereoselectivitives.
Each of the two hydroxyl groups of isosorbide can be alkylated selectively, either by direct alkylation with benzyl chloride or allyl bromide according to the reaction conditions, or by a three-step procedure involving selective monoacetylation, alkylation with four different reagents, and finally deacetylation. Monobutyl and monomethyl derivatives from isosorbide are also described.
The invention consists of esters of anhydrosugar alcohols useful as plasticizers for polymeric compounds. Specifically, esters are formed of bis-anhydrohexitols, such as isosorbide, isomannide and isosiditide, and used as substitutes for the phthalate-based plasticizers in common use. The bis-anhydrohexitols are preferably produced from biological sources.
Synthesis of novel chiral imidazolium-based ionic liquids derived from isosorbide and their applications in asymmetric aza Diels–Alder reaction
作者:Olivier Nguyen Van Buu、Audrey Aupoix、Giang Vo-Thanh
DOI:10.1016/j.tet.2009.01.055
日期:2009.3
A novel family of chiral imidazolium-based ionic liquids containing a Chiral moiety and a free hydroxyl function has been designed and synthesized using isosorbide as a biorenewable substrate. These chiral ionic liquids were found to catalyze the aza Diels-Alder reaction to give good yields and moderate diastereoselectivities. Chiral ionic liquids are recycled while their efficiency is preserved. (C) 2009 Elsevier Ltd. All rights reserved.