Asymmetric synthesis of propargylic alcohols catalyzed by (−)-MITH

This investigation describes that in the presence of 2.5 mol % of (−)-2-exo-morpholinoisobornane-10-thiol (MITH) 1, catalytic asymmetric alkynylation of aldehydes gives enantioenriched propargylic alcohols with good enantioselectivities.

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(1S)-1,3-Diphenyl-prop-2-yn-1-olC15H12O86% ee[α]D27=-2.4 (c 1.2, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-3-Phenyl-1-p-tolyl-prop-2-yn-1-olC16H14O86% ee[α]D27=-5.2 (c 1.2, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-3-Phenyl-1-m-tolyl-prop-2-yn-1-olC16H14O85% ee[α]D27=-5.8 (c 1.3, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-3-Phenyl-1-o-tolyl-prop-2-yn-1-olC16H14O86% ee[α]D27=+12.2 (c 1.2, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-1-(4-Chloro-phenyl)-3-phenyl-prop-2-yn-1-olC15H11ClO86% ee[α]D27=-7.9 (c 1.4, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-1-(3-Chloro-phenyl)-3-phenyl-prop-2-yn-1-olC15H11ClO86% ee[α]D27=-14.2 (c 1.5, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-1-(2-Chloro-phenyl)-3-phenyl-prop-2-yn-1-olC15H11ClO83% ee[α]D27=+46.2 (c 1.4, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-1-(4-Methoxy-phenyl)-3-phenyl-prop-2-yn-1-olC16H14O280% ee[α]D27=-4.2 (c 1.7, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-3-Phenyl-1-(4-trifluoromethyl-phenyl)-prop-2-yn-1-olC16H11F3O87% ee[α]D27=-6.9 (c 1.4, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(3S)-1,5-Diphenyl-pent-1-en-4-yn-3-ol (5i)C17H14O61% ee[α]D27=-7.3 (c 0.5, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (3S)

(3S)-2-Methyl-1,5-diphenyl-pent-1-en-4-yn-3-olC18H16O71% ee[α]D27=+31.6 (c 1.0, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (3S)

(3S)-1,5-Diphenyl-pent-1-yn-3-olC17H16O49% ee[α]D27=+28.4 (c 1.1, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (3S)

(1S)-1-Phenyl-3-(4-trifluoromethyl-phenyl)-prop-2-yn-1-olC16H11F3O84% ee[α]D27=+1.3 (c 1.1, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-3-(4-Methoxy-phenyl)-1-phenyl-prop-2-yn-1-olC16H14O276% ee[α]D26=+1.9 (c 1.1, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-3-(4-Chloro-phenyl)-1-phenyl-prop-2-yn-1-olC15H11ClO66% ee[α]D26=+2.6 (c 1.0, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)

(1S)-1-Phenyl-hept-2-yn-1-olC13H16O75% ee[α]D25=-18.1 (c 1.3, CHCl3)Source of chirality: asymmetric catalysisAbsolute configuration: (1S)