Resolution of (±)-2,2′-dihydroxy-1,1′-binaphthyl-3,3′-dicarboxylic acid using (1R,2R)-trans-cyclohexane-1,2-diamine

A simple and efficient method has been developed to resolve (±)-2,2′-dihydroxy-1,1′-binaphthyl-3,3′-dicarboxylic acid [(±)-BINOL-3,3′-dicarboxylic acid] (±)-1 using inexpensive and readily accessible chiral resolving agent (1R,2R)-trans-cyclohexane-1,2-diamine 2. Enantiomers of BINOL-3,3′-dicarboxylic acid were obtained in good yields and enantiomeric purity, for example, (S)-(−)-1 was isolated in 34% yield with >99% ee and (R)-(+)-1 was obtained in 36% yield with >99% ee. The formation of diastereomeric salt A between (S)-BINOL-3,3′-dicarboxylic acid and (1R,2R)-trans-cyclohexane-1,2-diamine was ascertained by using IR, single crystal X-ray crystallography, and HRMS.

Figure optionsDownload as PowerPoint slide

(S)-2,2′-Dihydroxy-[1,1′-binaphthalene]-3,3′-dicarboxylic acidC22H14O6[α]D25 = −189 (c 1.06, pyridine)source of chirality: ResolutionAbsolute configuration: (S)