Design and synthesis of spiro bis(1,2,3-triazolium) salts as chiral ionic liquids

Room temperature chiral spiro ionic liquids 1 and 2 based on 1,2,3-triazolium salts, were synthesized via an intramolecular double Huisgen reaction. The preparation of the enantiomerically pure spiro triazolium salts was achieved by resolution by HPLC using a chiral stationary phase column and subsequent N-dialkylations of spiro triazoles 6 and 10.

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(R)-(6-(but-3-yn-1-yl)-4,5,6,7-Tetrahydro-[1,2,3]triazolo[1,5-a]pyridin-6-yl)methanolC11H15N3Oee = 100%[α]D22=+10.4 (c 0.91, CHCl3)Source of chirality: resolutionAbsolute configuration: R

(R)-(6-(but-3-yn-1-yl)-4,5,6,7-Tetrahydro-[1,2,3]triazolo[1,5-a]pyridin-6-yl)methyl trifluoromethanesulfonateC12H14F3N3O3See = 100%[α]D18=+3.8 (c 0.94, CHCl3)Source of chirality: resolutionAbsolute configuration: R

(M)-5,7,7′,8′-Tetrahydro-4H,5′H-6,6′-spirobi[[1,2,3]triazolo[1,5-a]pyridine]C11H14N6ee = 100%[α]D17=-3.4 (c 0.41, CHCl3)Source of chirality: resolutionAbsolute configuration: M

(M)-2,2′-Dihexyl-5,5′,7,7′-tetrahydro-4H,4′H-6,6′-spirobi[[1,2,3]triazolo[1,5-a]pyridine]-2,2′-diium diiodideC23H40I2N6ee = 100%[α]D19=-31.3 (c 0.20, CH2Cl2)Source of chirality: resolutionAbsolute configuration: M

(M)-2,2′-Dihexyl-5,5′,7,7′-tetrahydro-4H,4′H-6,6′-spirobi[[1,2,3]triazolo[1,5-a]pyridin-2,2′-iium] dibis(trifluoromethanesulfonyl)amidateC27H40F12N8O8S4ee = 100%[α]D22=-11.3 (c 0.97, CH2Cl2)Source of chirality: resolutionAbsolute configuration: M