Use of triazole-ring formation to attach a Ru/TsDPEN complex for asymmetric transfer hydrogenation to a soluble polymer

The cycloaddition of a chiral ligand containing a terminal alkyne to a soluble polymer containing an azide provides a convenient means for the attachment of an asymmetric transfer hydrogenation catalyst to a soluble polymer support. Using these ligands in complexes with Ru(II), gave good results in terms of conversion and enantioselectivity (up to 95% ee) in ketone reduction reactions.

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N-[(R,R)-2-(Prop-2-ynyloxyethylamino)-1,2-diphenylethyl]-4-methyl benzenesulfonamideC26H28N2O3See = 100%[α]D35=+5.6 (c 0.22, CHCl3)Source of chirality: Enantiomerically pure diamine.Absolute configuration: (R,R)

N-[(R,R)-2-(1-Phenoxymethyl-1H-1,2,3-triazol-4-yl)methoxy ethylamino)-1,2-diphenylethyl]-4-methylbenzenesulfonamideC35H39N5O4See = 100%[α]D32=+6.7 (c 0.115, CHCl3)Source of chirality: Enantiomerically pure diamine.Absolute configuration: (R,R)

N-[(R,R)-2-(1-Benzyl-1H-1,2,3-triazol-4-yl)butylamino)-1,2-diphenylethyl]-4-methylbenzene-sulfonamideC34H37N5O2See = 100%[α]D30=+4.7 (c 0.315, CHCl3)Source of chirality: enantiomerically pure diamine.Absolute configuration: (R,R)

N-[(R,R)-2-(Hex-5-ynylamino)-1,2-diphenylethyl]-4-methyl BenzenesulfonamideC27H30N2O2See = 100%[α]D24=-26.6 (c 0.38, CHCl3)Source of chirality: enantiomerically pure diamine.Absolute configuration: (R,R)