Chiral pyridinium-based ionic liquids containing the (1R,2S,5R)-(−)-menthyl group

A novel class of chiral pyridinium salts in which the chirality resides in the cation have been prepared and characterized. The physicochemical and anti-microbial properties have been determined. The group of prepared salts contained chiral ionic liquids and decomposable chiral pyridinium chlorides.

Graphical abstractA novel class of chiral pyridinium salts in which the chirality resided in the cation have been prepared and characterized. The physicochemical and anti-microbial properties have been determined. The group of prepared salts contained chiral ionic liquids and decomposable chiral pyridinium chlorides.Figure optionsDownload full-size imageDownload as PowerPoint slide

1-[(1R,2S,5R)-(−)-Menthoxymethyl]pyridinium chlorideC16H26ClNO[α]D20=-124.2 (c 0.9, EtOH)Chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-2-methylpyridinium chlorideC17H28ClNO[α]D20=-99.7 (c 0.5, EtOH)Chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-3-methylpyridinium chlorideC17H28ClNO[α]D20=-126.9 (c 0.6, EtOH)Chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-4-methylpyridinium chlorideC17H28ClNO[α]D20=-117.1 (c 1.3, EtOH)Chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

4-Ethyl-1-[(1R,2S,5R)-(−)-Menthoxymethyl]pyridinium chlorideC18H30ClNO[α]D20=-124.8 (c 1.0, EtOH)Chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

4-tert-Butyl-1-[(1R,2S,5R)-(−)-menthoxymethyl]pyridinium chlorideC20H34ClNO[α]D20=-102.7 (c 1.3, EtOH)Chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

5-Hydroxy-1-[(1R,2S,5R)-(−)-menthoxymethyl]-2-methylpyridinium chlorideC17H28ClNO2[α]D20=-120.9 (c 1.1, EtOH)Chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

3-Carbamoyl-1-[(1R,2S,5R)-(−)-menthoxymethyl]pyridinium chlorideC17H27ClN2O2[α]D20=-122.2 (c 1.0, EtOH)Decomposable chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

3-Hydroxy-1-[(1R,2S,5R)-(−)-menthoxymethyl]pyridinium chlorideC16H26ClNO2[α]D20=-147.3 (c 1.0, EtOH)Decomposable chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-4-(dimethylamino)pyridinium chlorideC18H31ClN2O[α]D20=-117.8 (c 0.5, EtOH)Chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-3-(dimethylamino)pyridinium chlorideC18H31ClN2O[α]D20=-154.6 (c 1.0, EtOH)Decomposable chiral pyridinium chlorideAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]pyridinium tetrafluoroborateC16H26BF4NO[α]D20=-116.5 (c 0.7, EtOH)Chiral pyridinium tetrafluoroborateAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-2-methylpyridinium tetrafluoroborateC17H28BF4NO[α]D20=-116.3 (c 1.0, EtOH)Chiral pyridinium tetrafluoroborateAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-3-methylpyridinium tetrafluoroborateC17H28BF4NO[α]D20=-116.9 (c 1.0, EtOH)Chiral pyridinium tetrafluoroborateAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-4-methylpyridinium tetrafluoroborateC17H28BF4NO[α]D20=-109.9 (c 0.7, EtOH)Chiral pyridinium tetrafluoroborateAbsolute configuration: (1R,2S,5R)

4-Ethyl-1-[(1R,2S,5R)-(−)-menthoxymethyl]pyridinium tetrafluoroborateC18H30BF4NO[α]D20=-112.2 (c 1.1, EtOH)Chiral pyridinium tetrafluoroborateAbsolute configuration: (1R,2S,5R)

5-Hydroxy-1-[(1R,2S,5R)-(−)-menthoxymethyl]-2-methylpyridinium tetrafluoroborateC17H28BF4NO2[α]D20=-108.9 (c 1.0, EtOH)Chiral pyridinium tetrafluoroborateAbsolute configuration: (1R,2S,5R)

3-Carbamoyl-1-[(1R,2S,5R)-(−)-menthoxymethyl]pyridinium tetrafluoroborateC17H27BF4N2O2[α]D20=-111.9 (c 1.0, EtOH)Chiral pyridinium tetrafluoroborateAbsolute configuration: (1R,2S,5R)

3-Hydroxy-1-[(1R,2S,5R)-(−)-menthoxymethyl]pyridinium tetrafluoroborateC16H26BF4NO2[α]D20=-114.8 (c 1.0, EtOH)Chiral pyridinium tetrafluoroborateAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-4-(dimethylamino)pyridinium tetrafluoroborateC18H31BF4N2O[α]D20=-112.6 (c 1.0, EtOH)Chiral pyridinium tetrafluoroborateAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-3-(dimethylamino)pyridinium tetrafluoroborateC18H31BF4N2O[α]D20=-139.4 (c 0.5, EtOH)Chiral pyridinium tetrafluoroborateAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]pyridinium perchlorateC16H26ClNO5[α]D20=-110.9 (c 0.6, EtOH)Chiral pyridinium perchlorateAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]pyridinium iodideC16H26INO[α]D20=-50.9 (c 0.8, EtOH)Chiral pyridinium iodideAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]pyridinium hexafluorophosphateC16H26F6NOP[α]D20=-97.6 (c 1.0, EtOH)Chiral pyridinium hexafluorophosphateAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]pyridinium bis(trifluoromethanesulfonyl)imideC18H26F6N2O5S2[α]D20=-70.9 (c 1.4, EtOH)Chiral ionic liquidAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-2-methylpyridinium bis(trifluoromethanesulfonyl)imideC19H28F6N2O5S2[α]D20=-77.2 (c 1.1, EtOH)Chiral ionic liquidAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-3-methylpyridinium bis(trifluoromethanesulfonyl)imideC19H28F6N2O5S2[α]D20=-70.3 (c 1.3, EtOH)Chiral ionic liquidAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-4-methylpyridinium bis(trifluoromethanesulfonyl)imideC19H28F6N2O5S2[α]D20=-71.2 (c 1.0, EtOH)Chiral ionic liquidAbsolute configuration: (1R,2S,5R)

4-ethyl-1-[(1R,2S,5R)-(−)-Menthoxymethyl]pyridinium bis(trifluoromethanesulfonyl)imideC20H30F6N2O5S2[α]D20=-69.7 (c 0.5, EtOH)Chiral ionic liquidAbsolute configuration: (1R,2S,5R)

4-tert-Butyl-1-[(1R,2S,5R)-(−)-menthoxymethyl]pyridinium bis(trifluoromethanesulfonyl)imideC22H34F6N2O5S2[α]D20=-70.4 (c 1.6, EtOH)Chiral ionic liquidAbsolute configuration: (1R,2S,5R)

3-Carbamoyl-1-[(1R,2S,5R)-(−)-menthoxymethyl]pyridinium bis(trifluoromethanesulfonyl)imideC19H27F6N3O6S2[α]D20=-75.4 (c 1.2, EtOH)Chiral ionic liquidAbsolute configuration: (1R,2S,5R)

1-[(1R,2S,5R)-(−)-Menthoxymethyl]-3-(dimethylamino)pyridinium bis(trifluoromethanesulfonyl)imideC20H31F6N3O5S2[α]D20=-92.5 (c 0.85, EtOH)Chiral ionic liquidAbsolute configuration: (1R,2S,5R)