| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1347985 | Tetrahedron: Asymmetry | 2007 | 10 Pages |
Copper complexes of chiral iminopyridines prepared from camphane-derived ketones and picolylamine catalyzed the enantioselective Henry (nitroaldol) reaction between nitromethane and a number of aromatic and aliphatic aldehydes with high yields and good enantioselectivities. Iminopyridines derived from (1R)-(+)-camphor and (1S)-(+)-ketopinic acid gave the best results to afford the opposite enantiomers in each case, despite the fact they have the same stereochemical pattern at the camphane skeleton. The reactions were carried out without air or moisture exclusion.
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(E)-N-((1R,4R)-1,7,7-Trimethylbicyclo[2.2.1]heptan-2- ylidene)(pyridin-2-yl)methanamineC16H22N2[α]D25=-24.2 (c 0.91, CHCl3)Source of chirality: (1R)-(+)-camphorAbsolute configuration: (1R,4R)
(E)-N-((1R,4R)-1,7,7-Trimethylbicyclo[2.2.1]heptan-2-ylidene)(6-methylpyridin-2-yl)methanamineC17H24N2[α]D25=-23.9 (c 0.92, CHCl3)Source of chirality: (1R)-(+)-camphorAbsolute configuration: (1R,4R)
(E)-N-((1R,4R)-1,7,7-Trimethylbicyclo[2.2.1]heptan-2-ylidene)-2-(pyridin-2-yl)propan-2-amineC18H26N2[α]D25=-5.6 (c 0.99, CHCl3)Source of chirality: (1R)-(+)-camphorAbsolute configuration: (1R,4R)
(E)-N-((1R,4R)-1,7,7-Trimethylbicyclo[2.2.1]heptan-2-ylidene)-2-(pyridin-2-yl)ethanamineC17H24N2[α]D25=-28.4 (c 1.01, CHCl3)Source of chirality: (1R)-(+)-camphorAbsolute configuration: (1R,4R)
(E)-2-((Pyridin-2-yl)methylimino)-7,7-dimethylbicyclo[2.2.1]heptane-1-carboxylic acidC16H20N2O2[α]D25=+64.8 (c 1.11, CHCl3)Source of chirality: (1S)-(+)-ketopinic acid
((E,1S,4R)-2-((Pyridin-2-yl)methylimino)-7,7-dimethylbicyclo[2.2.1]heptan-1-yl)diphenylmethanolC28H30N2O[α]D25=+163.7 (c 0.97, CHCl3)Source of chirality: (1S)-(+)-ketopinic acidAbsolute configuration:(1S,4R)
((E)-2-((Pyridin-2-yl)methylimino)-7,7-dimethylbicyclo[2.2.1]heptan-1-yl)methanesulfonic acidC16H22N2O3S[α]D25=-39.6 (c 1.03, CHCl3)Source of chirality: (1S)-(+)-camphorsulfonic acid
(S)-(+)-2-Nitro-1-phenylethanolC8H9NO3Ee 72%[α]D25=+33.7 (c 1.05, CH2Cl2)Source of chirality: enantioselective Henry reactionAbsolute configuration: (S)
(S)-(+)-1-(2-Methoxyphenyl)-2-nitroethanolC9H11NO4Ee 85%[α]D25=+39.8 (c 1.05, CH2Cl2)Source of chirality: enantioselective Henry reactionAbsolute configuration: (S)
(R)-(−)-1-(2-Benzyloxyphenyl)-2-nitroethanolC15H15NO4Ee 83%[α]D25=-33.8 (c 1.10, CH2Cl2)Source of chirality: enantioselective Henry reactionAbsolute configuration: (R)
(R)-(−)-1-(2-Methylthiophenyl)-2-nitroethanolC9H11NO3SEe 83%[α]D25=-62.6 (c 1.09, CH2Cl2)Source of chirality: enantioselective Henry reactionAbsolute configuration: (R)
(S)-(+)-1-(2-Methylphenyl)-2-nitroethanolC9H11NO3Ee 82%[α]D25=+41.7 (c 1.07, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(S)
(S)-(+)-1-(2-Ethylphenyl)-2-nitroethanolC10H13NO3Ee 84%[α]D25=+33.6 (c 0.96, CH2Cl2)Source of chirality:Enantioselective Henry reactionAbsolute configuration:(S)
(S)-(+)-1-(2-Chlorophenyl)-2-nitroethanolC8H8ClNO3Ee 65%[α]D25=+40.3 (c 1.10, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(S)
(R)-(−)-1-(2-Bromophenyl)-2-nitroethanolC8H8BrNO3Ee 78%[α]D25=-29.2 (c 1.06, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(R)
(S)-(+)-1-(2-Iodophenyl)-2-nitroethanolC8H8BrNO3Ee 71%[α]D25=+24.2 (c 1.08, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(S)
(S)-(−)-2-Nitro-1-(2-nitrophenyl)ethanolC8H8N2O5Ee 27%[α]D25=-50.3 (c 0.38, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(S)
(S)-(+)-1-(4-Methoxyphenyl)-2-nitroethanolC9H11NO4Ee 78%[α]D25=+32.3 (c 1.05, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(S)
(R)-(−)-1-(4-Methylphenyl)-2-nitroethanolC9H11NO3Ee 81%[α]D25=-37.2 (c 1.14, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(R)
(S)-(+)-1-(4-Chlorophenyl)-2-nitroethanolC8H8ClNO3Ee 56%[α]D25=+24.7 (c 1.13, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(S)
(R)-(−)-2-Nitro-1-(4-nitrophenyl)ethanolC8H8N2O5Ee 27%[α]D25=-10.0 (c 1.06, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(R)
(S)-(+)-1-(3-Methoxyphenyl)-2-nitroethanolC9H11NO4Ee 76%[α]D25=+26.6 (c 0.97, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(S)
(R)-(−)-1-(3-Methylphenyl)-2-nitroethanolC9H11NO3Ee 72%[α]D25=-36.8 (c 1.09, CH2Cl2)Source of chirality:enantioselective Henry reactionAbsolute configuration:(R)
(R)-(−)-1-(3-Chlorophenyl)-2-nitroethanolC8H8ClNO3Ee 63%[α]D25=-27.2 (c 1.05, CH2Cl2)Source of chirality: enantioselective Henry reactionAbsolute configuration: (R)
(R)-(+)-1-Nitro-4-phenyl-2-butanolC10H13NO3Ee 74%[α]D25=+13.1 (c 0.51, CH2Cl2)Source of chirality: enantioselective Henry reactionAbsolute configuration: (R)
(R)-(−)-1-Cyclohexyl-2-nitroethanolC10H13NO3Ee 73%[α]D25=-14.7 (c 1.03, CHCl3)Source of chirality: enantioselective Henry reactionAbsolute configuration: (R)
(R)-(+)-4-Methyl-1-nitro-2-pentanolC6H13NO3Ee 79%[α]D25=+1.4 (c 1.01, CH2Cl2)Source of chirality: enantioselective Henry reactionAbsolute configuration: (R)
