6844
M. Aepkers, B. Wu¨nsch / Bioorg. Med. Chem. 13 (2005) 6836–6849
20
589
6.12. rac-cis-2-(2-Phenyl-1,3-dioxolan-4-yl)ethan-1-amine
(( )-12a)
yield (4S)-12c. Colorless oil, yield 41.7 mg (97%). ½aꢁ
ꢀ2.15 (c 1.74, CH2Cl2).
As described for the racemic amine ( )-12b, the racemic
azide ( )-10a (28.5 mg, 0.13 mmol) was hydrogenated to
yield ( )-12a. Colorless oil, yield 18.4 mg (73%). MS
6.17. (+)-(4R)-2-(2,2-Diphenyl-1,3-dioxolan-4-yl)ethan-1-
amine ((4R)-12c)
1
(CI): m/z (%) = 194 (MH, 100). H NMR (CDCl3): d
As described for the racemic amine ( )-12b, the azide
(4R)-10c (32.5 mg, 0.11 mmol) was hydrogenated to
[ppm] = 1.39 (br s, 2H, NH2), 1.78 (dtd, J = 13.7/7.2/
4.9 Hz, 1H, CH2CH2NH2), 1.87 (ddt, J = 13.7/7.6/
6.7 Hz, 1H, CH2CH2NH2), 2.86 (dt, J = 12.5/7.0 Hz,
1H, CH2CH2NH2), 2.92 (ddd, J = 12.5/7.3/6.4 Hz, 1H,
CH2CH2NH2), 3.70 (dd, J = 7.6/7.0 Hz, 1H, 5-H), 4.12
(dd, J = 7.6/6.7 Hz, 1H, 5-H), 4.31 (dddd, J = 7.6/7.0/
6.7/4.9 Hz, 1H, 4-H), 5.79 (s, 1H, 2-H), 7.34–7.39 (m,
3H, arom. H in m- and p-position), 7.45–7.49 (m, 2H,
20
589
yield (R)-12c. Colorless oil, yield 30.0 mg (100%). ½aꢁ
+2.08 (c 1.35, CH2Cl2).
6.18. rac-trans-2-(2-Phenyl-1,3-dioxolan-4-yl)ethan-1-
amine (( )-13a)
As described for the racemic amine ( )-12b, the racemic
azide ( )-11a (24.1 mg, 0.11 mmol) was hydrogenated to
yield ( )-13a. Colorless oil, yield 13.3 mg (63%). MS
arom. H in o-position). IR (film): m [cmꢀ1] = 3392 (m,
~
m
NH), 2928, 2884 (m, mCH), (193.25) HR-MS: Calcd.
1
for MꢀH 192.1025. Found: 192.1025.
(CI): m/z (%) = 194 (MH, 100). H NMR (CDCl3): d
[ppm] = 1.44 (br s, 2H, NH2), 1.69 (dtd, J = 13.7/7.0/
4.3 Hz, 1H, CH2CH2NH2), 1.87 (dddd, J = 13.7/8.2/
7.0/6.4 Hz, 1H, CH2CH2NH2), 2.85 (dt, J = 12.5/
7.0 Hz, 1H, CH2CH2NH2), 2.93 (ddd, J = 12.5/7.3/
6.4 Hz, 1H, CH2CH2NH2), 3.63 (dd, J = 7.3/6.4 Hz,
1H, 5-H), 4.27 (dd, J = 7.3/6.4 Hz, 1H, 5-H), 4.32 (dtd,
J = 8.2/6.4/4.3 Hz, 1H, 4-H), 5.92 (s, 1H, 2-H), 7.34–
7.39 (m, 3H, arom. H in m- and p-position), 7.44–7.48
~
6.13. rac-cis-2-(2-Ethyl-2-phenyl-1,3-dioxolan-4-yl)ethan-
1-amine ( )-(12b)
Racemic azide ( )-10b (22.3 mg, 0.09 mmol) was dis-
solved in THF (5 mL), Pd/C (5 %, 2.2 mg) was added,
and the suspension was stirred under a H2 atmosphere
(1 bar) at room temperature for 90 min. The mixture
was filtered through Celiteꢂ and the filtrate was concen-
trated in vacuo. Colorless oil, yield 17.9 mg (90%). MS
(CI): m/z (%) = 222 (MH, 100), 88 (O–CH2–CH–
(m, 2H, arom.
H in o-position). IR (film): m
[cmꢀ1] = 3389 (m, mNH), 2924, 2876 (m, mCH). HR-MS:
Calcd for MꢀH 192.1025. Found: 192.1025.
1
(CH2)2– NH2 + H, 38). H NMR (CDCl3): d [ppm] =
0.88 (t, J = 7.3 Hz, 3H, CH2CH3), 1.45 (br s, 2H,
NH2), 1.70 (dtd, J = 13.7/7.0/4.9 Hz, 1H, CH2CH2NH2),
1.82 (dq, J = 13.7/7.0 Hz, 1H, CH2CH2NH2), 1.88 (q,
J = 7.3 Hz, 2H, CH2CH3), 2.82 (dt, J = 12.5/7.0 Hz,
1H, CH2CH2NH2), 2.88 (dt, J = 12.5/7.0 Hz, 1H,
CH2CH2NH2), 3.58 (t, J = 7.0 Hz, 1H, 5-H), 3.87 (t,
J = 7.0 Hz, 1H, 5-H), 3.99 (qd, J = 7.0/4.9 Hz, 1H, 4-
H), 7.26–7.35 (m, 3H, arom. H in m- and p-position),
6.19. rac-trans-2-(2-Ethyl-2-phenyl-1,3-dioxolan-4-
yl)ethan-1-amine (( )13b)
As described for the racemic amine ( )-12b, the azide
( )-11b (24.7 mg, 0.10 mmol) was hydrogenated to yield
racemic ( )-13b. Colorless oil, yield 19.9 mg (90%). MS
1
(CI): m/z (%) = 222 (MH, 100). H NMR (CDCl3): d
[ppm] = 0.85 (t, J = 7.3 Hz, 3H, CH2CH3), 1.42 (br s,
2H, NH2), 1.48 (dtd, J = 13.7/7.2/4.9 Hz, 1H,
CH2CH2NH2), 1.61 (dddd, J = 13.7/7.9/7.0/6.4 Hz, 1H,
CH2CH2NH2), 1.86 (q, J = 7.3 Hz, 2H, CH2CH3), 2.77
(dt, J = 12.5/7.0 Hz, 1H, CH2CH2NH2), 2.84 (ddd,
J = 12.5/7.5/6.4 Hz, 1H, CH2CH2NH2), 3.35 (t,
J = 8.2 Hz, 1H, 5-H), 4.14 (dd, J = 8.2/6.1 Hz, 1H, 5-
H), 4.25 (tdd, J = 8.1/6.1/4.9 Hz, 1H, 4-H), 7.25–7.34
(m, 3H, arom. H in m- and p-position), 7.43–7.47 (m,
~
7.40–7.44 (m, 2H, arom. H in o-position). IR (film): m
[cmꢀ1] = 3368 (m, mNH), 2938, 2878 (s, mCH). HR-MS:
Calcd 221.1416. Found: 221.1416.
6.14. (+)-2-[(2R,4S)-2-Ethyl-2-phenyl-1,3-dioxolan-4-
yl]ethan-1-amine ((2R,4S)-12b)
As described for the racemic amine ( )-12b, the azide
(2R,4S)-10b (27.2 mg, 0.11 mmol) was hydrogenated to
yield (2R,4S)-12b. Colorless oil, yield 21.6 mg (89%).
2H, arom. H in o-position). IR (film): m [cmꢀ1] = 3368
~
(m, mNH), 2974, 2938, 2877 (s, each, mCH). HR-MS: Calcd
221.1416. Found: 221.1420.
20
½aꢁ +20.6 (c 1.03, CH2Cl2).
589
6.15. (ꢀ)-2-[(2S,4R)-2-Ethyl-2-phenyl-1,3-dioxolan-4-
yl]ethan-1-amine ((2S,4R)-12b)
6.20. (ꢀ)-2-[(2S,4S)-2-Ethyl-2-phenyl-1,3-dioxolan-4-
yl]ethan-1-amine ((2S,4S)-13b)
As described for the racemic amine ( )-12b, the azide
(2S,4R)-10b (19.8 mg, 0.08 mmol) was hydrogenated to
yield (2S,4R)-12b. Colorless oil, yield 17.7 mg (100%).
As described for the racemic amine ( )-12b, the azide
(2S,4S)-11b (24.7 mg, 0.10 mmol) was hydrogenated to
yield (2S,4S)-13b. Colorless oil, yield 21.0 mg (95%).
20
20
½aꢁ ꢀ17.4 (c 0.85, CH2Cl2).
½aꢁ ꢀ15.0 (c 1.01, CH2Cl2).
589
589
6.16. (ꢀ)-(4S)-2-(2,2-Diphenyl-1,3-dioxolan-4-yl)ethan-1-
amine ((4S)-12c)
6.21. (+)-2-[(2R,4R)-2-Ethyl-2-phenyl-1,3-dioxolan-4-
yl]ethan-1-amine ((2R,4R)-13b)
As described for the racemic amine ( )-12b, the azide
(4S)-10c (47.3 mg, 0.16 mmol) was hydrogenated to
As described for the racemic amine ( )-12b, the azide
(2R,4R)-11b (24.7 mg, 0.10 mmol) was hydrogenated