ORDER
REPRINTS
CHIRAL ALIPHATIC AND ARYLALKYL AMINES
575
153.5◦–154◦C (methanol/ether); 151◦–152◦C (24); MH+, 74. (R)-2-Pentylamine.
HCl: 175.5◦–176◦C (methanol/ether); 168◦C (racemate)(23); MH+, 88. (R)-2-
hexylamine. HCl: 106◦–107◦C (methanol/ether); 102◦–103◦C(23); MH+, 102.
(R)-2-heptylamine.HCl: 100◦–101◦C (hexane); 81◦–83◦C (racemate)(23) MH+,
116. (R)-2-octylamine.HCl: 89◦–90◦C (hexane); 90◦–91◦C(23); MH+, 130. (R)-
2-undecylamine.HCl: 85◦C (hexane); 84◦C (racemate)(23); MH+, 172. (R)-1-
phenylethylamine.HCI:171.5◦–172◦C (methanol/ether); 171◦–173◦C(25);
MH+, 122; also m/z 106, 105. (R)-2-phenylisopropylamine.HCl: l54◦–155◦C
(methanol/ether); 156◦C(23); MH+, 136.
Each of the alkyl and arylalkylamines (as the trifluoroacetyl-L-prolyl deriva-
tive) and N-acetyl amides was further characterized by comparison of its gas chro-
matographic retention time to that of an authentic sample.
Alternatively, the filtrates were added to a solution of oxalic acid (180 mg,
2 mmol) in ether (15 mL), and the oxalate salt was filtered and washed with ether.
The filtrates were rotary evaporated at 70◦C, the residue was loaded onto a column
of silica gel (4.0 g), and the N-acetyl amide (enriched in the R-enantiomer) was
eluted with hexane:ethyl acetate (1:1) (some of the excess oxalic acid also elutes
under these conditions).
Experimental data for characterization of the (S)-amine oxalates (recrystal-
lized from methanol-ether), all of which are new compounds, are: (S)-2-
butylamine.oxalate: 152.5◦–153◦C; 1NMR (D2O): δ 0.80 (t, 3H, terminal CH3),
δ 1.15 (d, 3H, α-CH3), δ 1.48 (m, 2H, β-CH2), δ 3.15 (m, 1H, α-CH). Elemental
analysis: calculated (found): %C = 44.17 (44.14); %H = 8.03 (8.15); %N = 8.58
(8.38).
(S)-2-pentylamine.oxalate: 149◦–150◦C; 1NMR (D2O): δ 0.80 (t, 3H, ter-
minal CH3), δ 1.15 (d, 3H, α-CH3), δ 1.27 (m, 2H, γ -CH2), δ 1.41 (m, 2H, β-CH2).
δ 3.22 (m,1H, α-CH). Elemental analysis: calculated (found): %C = 47.45 (47.54);
%H = 8.53 (8.76); %N = 7.90 (7.81).
1
(S)-2-hexylamine.oxalate: 141◦–143◦C; NMR (D2O): δ 0.78 (t, 3H, ter-
minal CH3), δ 1.14 (d, 3H, α-CH3), δ 1.21 (m, 4H, γ ,δ-CH2), δ 1.47 (m, 2H,
β-CH2), δ 3.21 (m, 1H, α-CH). Elemental analysis: calculated (found): % C =
50.25(50.04); %H = 8.96 (8.71); % N = 7.32 (7.18).
(S)-2-heptylamine.oxalate: 103◦–104◦C; 1NMR (D2O): δ 0.75 (t, 3H termi-
nal CH3), δ 1.05–1.30 (m, 9H, α-CH3) plus γ ,δ,ꢀ-CH2), δ 1.45 (m, 2H, β-CH2), δ
3.21 (m, 1H, α-CH). Elemental analysis: calculated (found): %C = 52.67 (52.30);
%H = 9.33 (9.15); %N = 6.82 (6.61).
1
(S)-2-octylamine.oxalate: 109◦–111◦C; NMR (D2O): δ 0.74 (t, 3H, ter-
minal CH3), δ 1.05–130 (m, 11H, α-CH3) plus γ ,δ,ε,φ-CH2,) δ 1.44 (m, 2H,
β-CH2), δ 3.19 (m, 1H, α-CH). Elemental analysis: calculated (found): %C =
54.77 (54.01); %H = 9.65 (9.98); %N = 6.39 (6.19).
1
(S)-2-undecylamine.oxalate: 103◦–107◦C; NMR (D2O): δ 0.72 (t, 3H,
terminal CH3), δ 1.05–1.30 (m, 17H, α-CH3) plus (7 × CH2), δ 1.48 (m, 2H,