Chemoenzymatic preparation of optically active anthracene derivatives

Syntheses and lipase-catalyzed resolutions of a trans-2-aminocyclopentanol rac-2 and trans-cyclopentane-1,2-diamine rac-3, bearers of an anthracene unit, have been effectively carried out. Burkholderia cepacia lipase catalyzed the transesterification of the β-amino alcohol with very high enantioselectivity (E > 200). Lipase B from Candida antarctica showed moderate enantioselectivity in the acetylation of the diamine when 1-phenylethyl acetate was used as an acyl donor. In addition, the treatment of the optically active diamine (1S,2S)-3 (ee = 95%) with pyridine-2,6-dicarbonyl dichloride yielded the bis(aminoamide) 6, which was tested as a chiral solvating agent (CSA) of carboxylic acids.

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(1S,2S)-2-[(9-Anthrylmethyl)(methyl)amino]cyclopentanolC21H23NOEe = 99%[α]D20=+56.4 (c 0.50, CHCl3)Source of chirality: Enzymatic resolutionAbsolute configuration: (1S,2S)

(1R,2R)-2-[(9-Anthrylmethyl)(methyl)amino]cyclopentyl acetateC23H25NO2Ee = 98%[α]D20=-52.5 (c 1.0, CHCl3)Source of chirality: Enzymatic resolutionAbsolute configuration: (1R,2R)

(1S,2S)-N-(9-Anthrylmethyl)-N-methylcyclopentane-1,2-diamineC21H24N2Ee = 95%[α]D20=+69.5 (c 0.50, CHCl3)Source of chirality: Enzymatic resolutionAbsolute configuration: (1S,2S)

(1R,2R)-N-{2-[(9-Anthrylmethyl)(methyl)amino]cyclopentyl}acetamideC23H26N2OEe = 85%[α]D20=-39.9 (c 0.50, CHCl3)Source of chirality: Enzymatic resolutionAbsolute configuration: (1R,2R)

(1S,2S)-tert-Butyl N-{2-[(9-anthrylmethyl)(methyl)amino]cyclopentyl}carbamateC26H32N2O2Ee = 95%[α]D20=+54.3 (c 1.0, CHCl3)Source of chirality: Enzymatic resolutionAbsolute configuration: (1S,2S)

(1′S,1″S,2′S,2″S)-N,N′-Bis{2-[(9-anthrylmethyl)(methyl)amino]cyclopentyl}pyridine-2,6-dicarboxamideC49H49N5O2Ee = 95%[α]D20=+141.5 (c 1.0, CHCl3)Source of chirality: Enzymatic resolutionAbsolute configuration: (1′S,1″S,2′S,2″S)