Lipase-promoted dynamic kinetic resolution of racemic β-hydroxyalkyl sulfones

A series of racemic aryl β-hydroxyalkyl sulfones have been successfully transformed into the corresponding optically active O-acetyl derivatives in high yields (up to 80%) with enantiomeric excesses more than 99% using a dynamic kinetic resolution procedure, in which a lipase-promoted kinetic resolution is combined with a concomitant ruthenium-catalysed racemization of the substrates.

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Phenyl 1-(2-hydroxy)propyl sulfoneC9H12O3SEe >99%[α]D = −12.0 (c 1.1, CHCl3)Source of chirality: enzymatic dynamic kinetic resolutionAbsolute configuration: R

p-Tolyl 1-(2-hydroxy)propyl sulfoneC10H14O3SEe >99%[α]D = −11.6 (c 1.1, CHCl3)Source of chirality: enzymatic dynamic kinetic resolutionAbsolute configuration: R

p-Tolyl 1-(2-hydroxy)butyl sulfoneC11H16O3SEe >99%[α]D = −9.2 (c 1.1, CHCl3)Source of chirality: enzymatic dynamic kinetic resolutionAbsolute configuration: R

Phenyl 1-(2-acetoxy)propyl sulfoneC11H14O4SEe >99%[α]D = −1.1 (c 1.1, CHCl3)Source of chirality: enzymatic dynamic kinetic resolutionAbsolute configuration: R

p-Tolyl 1-(2-acetoxy)propyl sulfoneC12H16O4SEe >99%[α]D = −1.1 (c 1.1, CHCl3)Source of chirality: enzymatic dynamic kinetic resolutionAbsolute configuration: R

p-Tolyl 1-(2-acetoxy)butyl sulfoneC13H18O4SEe >99%[α]D = −4.4 (c 1.1, CHCl3)Source of chirality: enzymatic dynamic kinetic resolutionAbsolute configuration: R

Phenyl1-(2-hydroxy)propyl sulfoneC9H12O3SEe = 85%[α]D = +10.2 (c 1.1, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: S

p-Tolyl 1-(2-hydroxy)propyl sulfoneC10H14O3SEe = 82%[α]D = +10.0 (c 1.1, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: S