| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1348755 | Tetrahedron: Asymmetry | 2006 | 8 Pages |
The synthesis of chiral ligands 4–18 derived from N-[(S)-α-phenylethyl]-trans-β-aminocyclohexanols (S,S,S)-1a and (R,R,S)-2 is described. Addition of diethylzinc to benzaldehyde catalyzed by ligands 4–18 (6 mol %) proceeds in fair to good yield (45–86%), and low to good enantioselectivities (1–76% ee). Highest enantioselectivities were induced by ligands (S,S,S)-4 and (S,S,S,S,R,R)-18 (76% and 68% ee, respectively). The configuration of the major enantiomer of carbinol 3 is (R) in both cases.
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(3aS,7aS)-3-N-[(S)-α-Phenylethyl]-octahydrobenzo[d]oxazoleC15H21NO[α]D = +39.8 (c 1, CHCl3)Source of chirality:(S)-α-phenylethylamineAbsolute configuration:(3aS,7aS,1′S)
(3aR,7aR)-3-N-[(S)-α-Phenylethyl]-octahydrobenzo[d]oxazoleC15H21NO[α]D = +23.8 (c 1, CHCl3)Source of chirality:(S)-α-phenylethylamineAbsolute configuration:(3aR,7aR,1′S)
(1S,2S)-N-[(S)-α-Phenylethyl]cyclohexane-1,2-diamineC14H22N2[α]D = +28.5 (c 1, CHCl3)Source of chirality:(S)-α-phenylethylamineAbsolute configuration:(1S,2S,1′S)
tert-Butyl (1S,2S)-2-N-[(S)-α-phenylethylamino]cyclohexylcarbamateC19H30N2O2[α]D = −17.5 (c 1, CHCl3)Source of chirality:(S)-α-phenylethylamineAbsolute configuration:(1S,2S,1′S)
(3aS,7aS)-1,3-Bis[(S)-α-phenylethyl]-octahydro-1H-benzo[d]imidazoleC23H30N2[α]D = +15.8 (c 1, CHCl3)Source of chirality:(S)-α-phenylethylamineAbsolute configuration:(3aS,7aS,1′S,1″S)
(3aS,7aS)-tert-Butyl 3-[(S)-α-phenylethyl]-octahydrobenzo[d]imidazole-1-carboxylateC20H30N2O2[α]D = +96.1 (c 1, CHCl3)Source of chirality:(S)-α-phenylethylamineAbsolute configuration:(3aS,7aS,1′S)
(4aS,8aS)-N,N′-1,4-Bis[(S)-α-phenylethyl]-octahydroquinoxalin-2(1H)-oneC24H30N2O[α]D = +5.0 (c 1, CHCl3)Source of chirality: (S)-α-phenylethylamineAbsolute configuration: (4aS,8aS,1′S,1″S)
(1S,2S)-N,N′-Bis-[(S)-α-phenylethyl]-N,N′-bis-(methylacetate)-1,2-cyclohexanediamineC28H38N2O4[α]D = +20.5 (c 1, CHCl3)Source of chirality: (S)-α-phenylethylamineAbsolute configuration: (1S,2S,1′S,1″S)
(1S,2S)-N,N′-Bis[(S)-α-phenylethyl]-bis(2-hydroxyethyl)-1,2-cyclohexanediamineC26H38N2O2[α]D = +47.0 (c 1, CHCl3)Source of chirality: (S)-α-phenylethylamineAbsolute configuration: (1S,2S,1′S,1″S)
(1S,2S)-N,N′-Bis[(S)-α-phenylethyl]-bis[(R)-2-hydroxyphenethyl]-1,2-cyclohexanediamineC38H46N2O2[α]D = −0.7 (c 1, CHCl3)Source of chirality: (S)-α-phenylethylamineAbsolute configuration: (1S,2S,1′S,1″S,2′R,2″R)
(1S,2S)-2-Azido-N-[(S)-α-phenylethyl]cyclohexanamineC14H20N4[α]D = +23.5 (c 1, CHCl3)Source of chirality: (S)-α-phenylethylamineAbsolute configuration: (1S,2S,1′S)
N,N′-Bis[(S)-α-phenylethyl]-bis[(R)-hydroxyphenethyl]-1,2-ethylendiamineC34H40N2O2[α]D = −47.2(c 1.10, CHCl3)Source of chirality: (S)-α-phenylethylamineAbsolute configuration: (1′S,1″S,2′R,2″R)
