Sugar Derived Crown Ethers and Their Analogs: Synthesis and Properties

Abstract

Receptors with the sugar unit incorporated into the macrocyclic structure -their synthesis and complexing abilities -are reviewed. The receptors with the disaccharide moieties (although such derivatives are rare) including sucrose are also described in this review.Dedicated to Professor Andras Liptak on the occasion of his 70 th birthday.

Synthesis of l‐threitol‐based crown ethers and their application as enantioselective phase transfer catalyst in Michael additions

“…Lariat ethers 6a and 7a generated ee values of 98/99%, while macrocycle 8a allowed an ee of 86%. The reason for the low yields may be the base-catalyzed dimerization side reaction of diethyl bromomalonate (17).…”

“…26,27 Stoddart performed pioneering work in preparing and investigating macrocycles built up from sugar alcohols such as L-iditol, L-threitol, and D-mannitol. [15][16][17]26,27 At that time, they had not yet studied the catalytic effects of these compounds in phase transfer reactions. Later on, a few articles were published on the synthesis of chiral crown ethers derived from diethyl L-tartrate, [28][29][30][31][32][33][34][35][36][37] but from among the macrocycles prepared, only a few were investigated as chiral phase transfer catalysts, which were not too efficient.…”

“…were synthesized. [15][16][17] A few of them proved to be efficient phase transfer catalysts in certain asymmetric reactions. …”

Synthesis of macrocyclic derivatives with di-sucrose scaffold

“…Carbohydrates are often used as platforms for the construction of macrocyclic receptors in optically pure form. [2][3][4][5] This refers, however, mostly to monosaccharides; [6][7][8][9][10][11] application of di-saccharides in chiral scaffolds has been rather limited. [12][13][14] Figure 1.…”

Synthesis of chiral pyridino-15-crown-5 type ligands containing α-D-hexapyranoside unit and their application in asymmetric synthesis

“…Therefore, these compounds should serv as useful tools for the separation of enantiomers, chiral recognition in enzymatic reactions and for the control of asymmetric reactions. 2 Stoddart et al were the first group that published the enantiomeric discriminating ability of certain sugar-based crown compounds towards the antipodes of chiral ammonium salts. 3 Although many optically active macrocycles incorporating one or more monosaccharide units have been synthesized, only a few have been successfully applied as catalysts in asymmetric reactions.…”