Novel carbohydrate-based chiral ammonium ionic liquids derived from isomannide

This report describes the synthesis and characterization of novel carbohydrate-based chiral ammonium ionic liquids using isomannide as a biorenewable substrate. The diastereomeric interactions of these chiral ammonium ionic liquids with racemic Mosher’s acid salt have been studied using NMR, which indicates their participation in chiral discrimination and shows their potential applications in chiral resolution.

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(1S,4R,5R,8R)-4-Ethoxy-8-(p-toluenesulfonyloxy)-2,6-dioxabicyclo [3.3.0] octaneC15H20O6S[α]D22=+91.4 (c 0.85, MeOH)Absolute configuration: (1S,4R,5R,8R)

(1R,4R,5R,8S)-4-Ethoxy-8-(benzylamino)-2,6-dioxabicyclo [3.3.0] octaneC15H21NO3[α]D22=+94.0 (c 1.076, MeOH)Absolute configuration: (1R,4R,5R,8S)

((1R,4R,5R,8S)-4-Ethoxy-2,6-dioxabicyclo [3.3.0] octan-8-yl)-dimethylbenzylammonium iodideC17H26NO3I[α]D22=+54.8 (c 0.96, MeOH)Absolute configuration: (1R,4R,5R,8S)

((1R,4R,5R,8S)-4-Ethoxy-2,6-dioxabicyclo [3.3.0] octan-8-yl)-dimethylbenzylammonium bis(triflic)imideC19H26N2O7S2F6[α]D22=+35.6 (c 0.88, MeOH)Absolute configuration: (1R,4R,5R,8S)

((1R,4R,5R,8S)-4-Ethoxy-2,6-dioxabicyclo [3.3.0] octan-8-yl)-dimethylbenzylammonium hexafluorophosphateC17H26NO3PF6[α]D22=+49.8 (c 0.92, MeOH)Absolute configuration: (1R,4R,5R,8S)

((1R,4R,5R,8S)-4-Ethoxy-2,6-dioxabicyclo [3.3.0] octan-8-yl)-dimethylbenzylammonium trifluoroacetateC19H26NO5F3[α]D22=+53.1 (c 1, MeOH)Absolute configuration: (1R,4R,5R,8S)

((1R,4R,5R,8S)-4-Ethoxy-2,6-dioxabicyclo [3.3.0] octan-8-yl)-dimethylbenzylammonium tetrafluoroborateC17H26NO3BF4[α]D22=+61.3 (c 1, MeOH)Absolute configuration: (1R,4R,5R,8S)

((1R,4R,5R,8S)-4-Ethoxy-2,6-dioxabicyclo [3.3.0] octan-8-yl)-dimethylbenzylammonium trifluorosulfonateC18H26NO6SF3[α]D22=+49.8 (c 0.92, MeOH)