| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1345412 | Tetrahedron: Asymmetry | 2013 | 6 Pages |
A convenient synthesis of δ,γ-unsaturated amino acids has been developed. After a mixture of (R)-tert-butanesulfinamide and glyoxylic acid with molecular sieves in CH2Cl2 was stirred for 42 h at room temperature, allylboronic acid pinacol ester was added to the mixture to give (R)-2-((R)-tert-butanesulfinamido)pent-4-enoic acid with high diastereoselectivity. The corresponding reaction of (Z)-crotylboronic acid pinacol ester produced no product; however, that of (E)-crotylboronic acid pinacol ester produced (2R,3S)-2-((R)-tert-butylsulfinamido)-3-methylpent-4-enoic acid with excellent diastereoselectivity.
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(2R,RS)-2-(tert-Butylsulfinamido)pent-4-enoic acidC9H17NO3S[α]D23=-32.6 (c 1.0, CHCl3)Source of chirality: (R)-tert-butanesulfinamideAbsolute configuration: (2R,RS)
(2R,3S,RS)-2-(tert-Butylsulfinamido)-3-methylpent-4-enoic acidC10H19NO3S[α]D23=-78.5 (c 1.0, CHCl3).Source of chirality: (R)-tert-butanesulfinamideAbsolute configuration: (2R,3S,RS)
(2S,3R,SS)-2-(tert-Butylsulfinamido)-3-methylpent-4-enoic acidC10H19NO3S[α]D30=+74.1 (c 1.0, CHCl3)Source of chirality: (S)-tert-butanesulfinamideAbsolute configuration: (2S,3R,SS)
(2R,3S,RS)-2-(tert-Butylsulfinamido)-3-propylpent-4-enoic acidC12H23NO3S[α]D29=-37.9 (c 1.0, CHCl3)Source of chirality: (R)-tert-butanesulfinamideAbsolute configuration: (2R,3S,RS)
(2S,3R,SS)-2-(tert-Butylsulfinamido)-3-propylpent-4-enoic acidC12H23NO3S[α]D29=+37.8 (c 1.3, CHCl3)Source of chirality: (S)-tert-butanesulfinamideAbsolute configuration: (2S,3R,SS)
(2R,RS)-2-(tert-Butylsulfinamido)-4-methylpent-4-enoic acidC10H19NO3S[α]D28=-33.9 (c 1.1, CHCl3)Source of chirality: (R)-tert-butanesulfinamideAbsolute configuration: (2R,RS)
(R)-2-Aminopent-4-enoic acidC5H9NO2[α]D25=+23.7 (c 0.11, H2O, 94% ee)Source of chirality: (R)-tert-butanesulfinamideAbsolute configuration: (R)
(2S,3R)-2-Amino-3-methylpent-4-enoic acidC6H11NO2[α]D26=+16.9 (c 0.61, H2O)Source of chirality: (S)-tert-butanesulfinamideAbsolute configuration: (2S,3R)
(2S,3R)-2-Amino-3-propylpent-4-enoic acidC8H14NO2[α]D25=-3.2 (c 0.62, MeOH).Source of chirality: (S)-tert-butanesulfinamideAbsolute configuration: (2S,3R)
(R)-2-Amino-4-methylpent-4-enoic acidC6H11NO2[α]D18=+40.7 (c 0.39, H2O)Source of chirality: (R)-tert-butanesulfinamideAbsolute configuration: (R)
(S)-2-Amino-4-hydroxy-4-methylpentanoic acidC6H13NO3[α]D31=-11.4 (c 0.51, MeOH)Source of chirality: (S)-tert-butanesulfinamideAbsolute configuration: (S)
