Enantioselective desymmetrization of prochiral allenic diols via cooperative catalysis of Pd(OAc)2 and a chiral phosphoric acid

The first non-enzymatic desymmetrization of prochiral allenic diols via cooperative binary catalysis of Pd(OAc)2 and (R)-STRIP has been reported. This method allows easy access to a series of optically active disubstituted dihydrofurans through palladium mediated 5-endo-trig cyclizations of allenic alcohol with high yields and good to excellent enantioselectivity. A broad substrate scope has been demonstrated.

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(R)-(5-Phenyl-2,5-dihydrofuran-3-yl)methanolC11H12O2[α]D20 = +170.0 (c 0.40, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-(3-Methoxyphenyl)-2,5-dihydrofuran-3-yl)methanolC12H14O3[α]D20 = +125.0 (c 0.27, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-(3-(Trifluoromethyl)phenyl)-2,5-dihydrofuran-3-yl)methanolC12H11F3O2[α]D20 = +97.9 (c 0.29, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-(m-Tolyl)-2,5-dihydrofuran-3-yl)methanolC12H14O2[α]D20 = +169.0 (c 0.2, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-(p-Tolyl)-2,5-dihydrofuran-3-yl)methanolC12H14O2[α]D20 = +96.2 (c 0.53, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-(3-Chlorophenyl)-2,5-dihydrofuran-3-yl)methanolC11H11ClO2[α]D20 = +143.8 (c 0.21, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-(2-Chlorophenyl)-2,5-dihydrofuran-3-yl)methanolC11H11ClO2[α]D20 = +164.8 (c 0.5, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-(4-Chlorophenyl)-2,5-dihydrofuran-3-yl)methanolC11H11ClO2[α]D20 = +174.2 (c 0.38, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-(3-Fluorophenyl)-2,5-dihydrofuran-3-yl)methanolC11H11FO2[α]D20 = +99.3 (c 0.30, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-(3-Bromophenyl)-2,5-dihydrofuran-3-yl)methanolC11H11BrO2[α]D20 = +97.3 (c 0.22, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-([1,1′-Biphenyl]-4-yl)-2,5-dihydrofuran-3-yl)methanolC17H16O2[α]D20 = +145.0 (c 0.16, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-(5-(Naphthalen-2-yl)-2,5-dihydrofuran-3-yl)methanolC15H14O2[α]D20 = +143.2 (c 0.25, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(S)-(5-Cyclohexyl-2,5-dihydrofuran-3-yl)methanolC11H18O2[α]D20 = +70.3 (c 0.33, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (S)

(R)-4-Methyl-2-phenyl-2,5-dihydrofuranC11H12O[α]D20 = +138.3 (c 0.2, CHCl3)Source of chirality: (R)-(5-phenyl-2,5-dihydrofuran-3-yl)methanolAbsolute configuration: (R)