| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1346095 | Tetrahedron: Asymmetry | 2012 | 5 Pages |
Various 1-acyl-2,4,10-trioxaadamantanes were prepared from the corresponding 1-methoxycarbonyl derivatives, via conversion to the N-acylpiperidine derivatives followed by reaction with a Grignard reagent in refluxing THF. These α-keto orthoformates were converted to the corresponding imines with 1-(S)-phenethyl amine (TiCl4/Et3N/toluene/reflux), with the Schiff bases being reduced further with NaBH4 (MeOH/0 °C) into the corresponding 1-(S)-phenethyl amines (diastereomeric excess 91:9 by NMR). Hydrogenolysis of the phenethyl group (Pd-C/MeOH) finally led to the 1-(aminoalkyl)trioxaadamantanes, which are chiral C-protected α-amino acids, in excellent overall yields.
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N-[(1S)-Phenethyl] (1S)-(2,4,10-trioxaadamant-3-yl)propylamineC18H25NO3[α]D24=-98.1 (c 1, CHCl3)Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S),(1S)
N-(1S)-Phenethyl (1S)-(2,4,10-trioxaadamant-3-yl)butylamineC19H27NO3[α]D24=-110.9 (c 1.38, CHCl3)Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S),(1S)
N-[(1S)-Phenethyl] (1S)-(2,4,10-trioxaadamant-3-yl)heptylamineC22H33NO3[α]D24=-73.2 (c 2.2, CHCl3);Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S),(1S)
N-[(1S)-Phenethyl] (1R)-(2,4,10-trioxaadamant-3-yl)heptylamineC22H33NO3[α]D24=-2.9 (c 0.46, CHCl3)Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S),(1R)
N-[(1S)-Phenethyl] (1S)-(2,4,10-trioxaadamant-3-yl)-3-methylbutylamineC20H29NO3[α]D24=-90.2 (c 1.8, CHCl3)Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S),(1S)
N-[(1S)-Phenethyl] (1S)-(2,4,10-trioxaadamant-3-yl)-4-methylpentylamineC21H31NO3[α]D24=-72.3 (c 2.15, CHCl3);Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S),(1S)
N-[(1S)-Phenethyl] (1S)-(2,4,10-trioxaadamant-3-yl)-2-phenethylamineC24H29NO3[α]D24=-72.2 (c 0.49, CHCl3)Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S),(1S)
(1S)-(2,4,10-Trioxaadamant-3-yl)propylamineC10H17NO3[α]D24=-14.1 (c 0.8, CHCl3)Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S)
(1S)-(2,4,10-Trioxaadamant-3-yl)butylamineC11H19NO3[α]D24=-35.7 (c 3.8, CHCl3)Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S)
(1S)-(2,4,10-Trioxaadamant-3-yl)heptylamineC14H25NO3[α]D24=-14.5 (c 1.25, CHCl3)Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S)
(1S)-(2,4,10-Trioxaadamant-3-yl)-3-methylbutylamineC12H21NO3[α]D24=-17.6 (c 0.64, CHCl3);Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S)
(1S)-(2,4,10-Trioxaadamant-3-yl)-4-methylpentylamineC13H23NO3[α]D24=-17.6 (c 1.7, CHCl3)Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S)
(1S)-(2,4,10-Trioxaadamant-3-yl)-2-phenethylamineC16H21NO3[α]D24=-23.7 (c 2.8, CHCl3)Source of chirality: chiral-auxiliary based asymmetric synthesisAbsolute configuration: (1S)
