| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1347617 | Tetrahedron: Asymmetry | 2008 | 6 Pages |
The combination of cross-metathesis and aza-Michael addition is an efficient method for generating piperidine alkaloids. Allosedridine and 2-epi-ethylnorlobelol were synthesized in six steps with ca. 25% overall yield. The aza-Michael addition is reversible for phenyl and alkyl ketones; however, the epimerization is not observed for the corresponding ester and amide.
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(−)-AllosedridineC8H17NO[α]D20=-20.7 (c 0.22, MeOH)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (2S, 2′R)
(−)-2-epi-EthylnorlobelolC9H19NO[α]D20=-6.8 (c 0.24, EtOH)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (2S, 2′R)
Methyl (2S)-1-[(1R)-1-phenylethyl]piperidineacetateC16H23NO2[α]D20=+39.2 (c 1, CHCl3)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (2S, αR)
Methyl (2R)-1-[(1R)-1-phenylethyl]piperidineacetateC16H23NO2[α]D20=+9.7 (c 1.5, CHCl3)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (2R, αR)
N-Methoxy-N-methyl (2S)-1-[(1R)-1-phenylethyl]piperidineacetamideC17H26N2O2[α]D20=+20.4 (c 1, CHCl3)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (2S, αR)
(R)-N-(1-Phenylethyl)-5-hexenyl amineC14H21N[α]D20=+46.8 (c 1, CHCl3)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (αR)
tert-Butyl 5-oxopentyl (R)-(1-phenylethyl)carbamateC18H27NO3[α]D20=+71.7 (c 1, CHCl3)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (αR)
tert-Butyl 7-[methoxy(methyl)amino]-7-oxo-(5,E)-hepten-yl-(R)-(1-phenylethyl)carbamateC22H34N2O4[α]D20=+54.0 (c 1, CHCl3)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (αR)
tert-Butyl (7-oxo-7-phenyl-(5,E)-heptenyl)-(R)-(1-phenylethyl)carbamateC26H33NO3[α]D20=+49.0 (c 1, CHCl3)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (αR)
1-[(2S)-1-[(1R)-1-Phenylethyl]-2-piperidinyl]-2-propanoneC26H23NO[α]D20=+41.4 (c 1.1, CHCl3)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (2S, αR)
Methyl (2S)-1-[(1R)-1-phenylethyl]piperidineacetateC17H25NO[α]D20=+32.6 (c 0.8, CHCl3)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (2S, αR)
(R)-1-((S)-1-((R)-1-Phenylethyl)-2-piperidinyl)propan-2-olC16H25NO[α]D20=+13.5 (c 0.4, CHCl3)Source of chirality: (R)-α-methylbenzylamineAbsolute configuration: (2S, 2′R, αR)
(R)-1-((S)-1-((R)-1-Phenylethyl)-2-piperidinyl)butan-2-olC17H27NO[α]D20=+5.8 (c 0.35, CHCl3)
