Enantiomerically pure α-pinene derivatives from material of 65% enantiomeric purity. Part 2: C2-symmetric N,N′-3-(2α-hydroxy)pinane diimines and diamines

The conversion of enantiomerically enriched (ee >99%) 2α-hydroxypinan-3-one and its oxime (obtained in previously described procedures∗ from α-pinene of 65% ee) into a range of derivatives with potential application in asymmetric synthesis was attempted. C2-Symmetrical compounds, ligands for potential catalysts, were synthesized from 2α-hydroxypinan-3-one and either aliphatic or aromatic diamines. Reduction or etherification/reduction of selected diiminodiols afforded respective diaminodiols and diaminoethers, which were further transformed into azolium salts. Reactions of dipinanediaminoethers with dichlorophenylphosphine and subsequent in situ oxidation of the products afford the respective stable phosphinediamide oxides. Four selected compounds were crystallographically studied.

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Di{(1S,1′S,2S,2′S,5S,5″S)-2-hydroxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ene}-diazaneC20H32N2O2Ee >99%[α]D20=-24.6 (c 1, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,5S,5′S)

Di{(1S,1′S,2S,2′S,5S,5′S)-2-benzyloxy-2,6,6-trimethyl-bicyclo[3.1.1]-hept-3-ene}-ethane-1,2-diamineC22H36N2O2Ee >99%[α]D20=7.6 (c 1, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,5S,5′S)

Di{(1S,1′S,2S,2′S,5S,5′S)-2-hydroxy-2,6,6-trimethyl-bicyclo[3.1.1]-hept-3-ene}-butane-1,4-diamineC24H40N2O2Ee >99%[α]D20=5.8 (c 0.5, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,5S,5′S)

Di{(1S,1′S,2S,2′S,5S,5″S)-2-hydroxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ene}-α,α′-p-xylene diamineC28H40N2O2Ee >99%[α]D20=16.0 (c 1, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,5S,5′S)

Di{(1S,1′S,2S,2′S,5S,5″S)-2-hydroxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ene}-benzene-1,2-diamineC26H36N2O2Ee >99%[α]D20=-140.3 (c 1, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,5S,5′S)

Di{(1S,1′S,2S,2′S,5S,5″S)-2-hydroxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ene}-benzene-1,3-diamineC26H36N2O2Ee >99%[α]D20=-14.8 (c 0.5, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,5S,5′S)

Di{(1S,1′S,2S,2′S,5S,5″S)-2-hydroxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ene}-benzene-1,4-diamineC26H36N2O2Ee >99%[α]D20=99.4 (c 0.5, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,5S,5′S)

Di{(1S,1′S,2S,2′S,5S,5″S)-2-methoxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ene}-ethane-1,2-diamineC24H40N2O2Ee >99%[α]D20=13.6 (c 0.51, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,5S,5′S)

Di{(1S,1′S,2S,2′S,5S,5″S)-2-benzoxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ene}-ethane-1,2-diamineC36H48N2O2Ee >99%[α]D20=101.4 (c 0.5, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,5S,5′S)

Di{(1S,1′S,2S,2′S,5S,5″S)-2-methoxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ene}-benzene-1,2-diamineC28H40N2O2Ee >99%[α]D20=-57.4 (c 1, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,5S,5′S)

Di{(1S,1′S,2S,2′S,3R,3′R,5S,5″S)-2-hydroxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ane}-ethane-1,2-diamineC22H40N2O2Ee >99%[α]D20=-46.5 (c 1, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,3R,3′R,5S,5′S)

Di{(1S,1′S,2S,2′S,3R,3′R,5S,5″S)-2-methoxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ane}-ethane-1,2-diamineC24H44N2O2Ee >99%[α]D20=-34.1 (c 1, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,3R,3′R,5S,5′S)

Di{(1S,1′S,2S,2′S,3R,3′R,5S,5″S)-2-benzoxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ane}-ethane-1,2-diamineC36H52N2O2Ee >99%[α]D20=-19.8 (c 0.2, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,3R,3′R,5S,5′S)

Di{(1S,1′S,2S,2′S,3R,3′R,5S,5″S)-2-methoxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ane}-benzene-1,3-diamineC28H42N2O2Ee >99%[α]D20=-93.5 (c 1, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S, 3R,3′R,5S,5′S)

Di{(1S,1′S,2S,2′S,3R,3′R,5S,5″S)-2-hydroxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ane}-benzene-1,3-diamineC26H40N2O2Ee >99%[α]D20=-177.8 (c 0.2, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,3R,3′R,5S,5′S)

1,3-Bis{(1S,1′S,2S,2′S,3R,3′R,5S,5″S)-2-benzoxy-2,6,6-trimethyl-bicyclo[3.1.1.]-hept-3-ane}-imidazolinium chloride dihydrateC37H51N2O2Cl·2H2OEe >99%[α]D20=-47.1 (c 0.2, CH3OH)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,3R,3′R,5S,5′S)

1,3-Di{(1S,1′S,2S,2′S,3R,3′R,5S,5″S)-2-methoxy-2,6,6-trimethyl-bicyclo[3.1.1.]hept-3-ane}-2-phenyl[1.3.2]diazaphospholidine 2-oxideC30H47N2O3PEe >99%[α]D20=+11.3 (c 1, CHCl3)Source of chirality: (+)-α-pineneAbsolute configuration: (1S,1′S,2S,2′S,3R,3′R,5S,5′S)