Diastereoselective alkynylation of glucose-modified imines with terminal alkynes

The copper(I)-catalyzed enantioselective alkynylation of aldimines incorporating a 2,3,4,6-tetrakis-O-pivaloyl-d-glucopyranosyl (Piv4Glc) chiral auxiliary with terminal alkynes is reported. The present system provides a versatile tool for the construction of optically active propargylamine derivatives. Good yields and enantiomeric excess values were achieved with an array of imines and biologically active, propargylamine derivatives.

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N-(2,3,4,6-Tetra-O-pivaloyl-β-d-glucopyranosyl)-1,3-diphenylprop-2-ynylamineC41H55NO9De = 90%[α]D20=+30.55 (c 0.036, CHCl3)Source of chirality: 2,3,4,6-tetra-O-pivaloyl-β-d-glucopyranoseAbsolute configuration: (R)

N-(2,3,4,6-Tetra-O-pivaloyl-β-d-glucopyranosyl)-1-(4-nitrophenyl)-3-phenylprop-2-ynylamineC41H54N2O11De = 91%[α]D20=+32.4 (c 0.032, CHCl3)Source of chirality: 2,3,4,6-tetra-O-pivaloyl-β-d-glucopyranoseAbsolute configuration: (R)

N-(2,3,4,6-Tetra-O-pivaloyl-β-d-glucopyranosyl)-1-(4-chlorophenyl)-3-phenylprop-2-ynylamineC41H54ClNO9De = 93%[α]D20=+36.6 (c 0.023, CHCl3)Source of chirality: 2,3,4,6-tetra-O-pivaloyl-β-d-glucopyranoseAbsolute configuration: (R)

N-(2,3,4,6-Tetra-O-pivaloyl-β-d-glucopyranosyl)-1-(3-trifluoromethyl)penyl-3-phenylprop-2-ynylamineC41H54N2O11De = 96%[α]D20=+16.9 (c 0.043, CHCl3)Source of chirality: 2,3,4,6-tetra-O-pivaloyl-β-d-glucopyranoseAbsolute configuration: (R)

N-(2,3,4,6-Tetra-O-pivaloyl-β-d-glucopyranosyl)-1-(4-trifluoromethyl)penyl-3-phenylprop-2-ynylamineC42H54F3NO9De = 93%[α]D20=+31.45 (c 0.027, CHCl3)Source of chirality: 2,3,4,6-tetra-O-pivaloyl-β-d-glucopyranoseAbsolute configuration: (R)

N-(2,3,4,6-Tetra-O-pivaloyl-β-d-glucopyranosyl)-1-(4-methylphenyl)-3-phenylprop-2-ynylamineC42H57NO9De = 92%[α]D20=+17.2 (c 0.073, CHCl3)Source of chirality: 2,3,4,6-tetra-O-pivaloyl-β-d-glucopyranoseAbsolute configuration: (R)

N-(2,3,4,6-Tetra-O-pivaloyl-β-d-glucopyranosyl)-1-(4- chlorophenyl)-hept-2-ynylamineC39H58ClNO9De = 78%[α]D20=+11.9 (c 0.056, CHCl3)Source of chirality: 2,3,4,6-tetra-O-pivaloyl-β-d-glucopyranoseAbsolute configuration: (R)

N-(2,3,4,6-Tetra-O-pivaloyl-β-d-glucopyranosyl)-1-(4-chlorophenyl)-3-(trimethylsilyl)-prop-2-ynylamineC38H58ClNO9SiDe = 28%[α]D20=+9.4 (c 0.039, CHCl3)Source of chirality: 2,3,4,6-tetra-O-pivaloyl-β-d-glucopyranoseAbsolute configuration: (R)