W. Seelen et al. / Tetrahedron Letters 44 (2003) 4491–4493
4493
Reagents and conditions: (a) HC(OMe)2NMe2, 110°C, 70%;
(b) H2NOH·HCl, MeOH, 50°C, 98%; (c) NaOMe, MeOH,
23°C, 77%; (d) H2NNH2, EtOH, 23°C, 4 M HCl in dioxane,
70%. 1H NMR (300 MHz, DMSO-d6, 298 K) of 4: l
(ppm)=13.60 (br.s, NH), 6.91 (br.s, NH2), 3.10 (sext.
J:7.0, 1H), 2.71–2.30 (m, 3H), 2.02–1.91 (m, 1H), 1.18 (d,
J=6.7, Me).
1
9. All new compounds were characterised by H/13C NMR,
MS, TLC and—if crystalline—melting point 1H NMR data
(300 MHz, 298 K) of selected compounds: 2 (CDCl3): l
(ppm)=5.26 (br.s, NH), 1.90 (tt, J=8.4, 5.0 Hz, 1H,
H-C(6)), 1.64 (s, 9H, tert-Bu), 0.92–0.87 (m, 2H), 0.68–62
(m, 2H). 3 (CDCl3): l (ppm)=3.25 (br.s, NH2), 5.33 (s, 1H,
H-(4)), 2.33 (tt, J=8.5, 5.2 Hz, 1H, H-C(6)), 1.62 (s, 9H,
tert-Bu), 0.99–0.93 (m, 2H), 0.66–0.61 (m, 2H). 5 (CDCl3):
l (ppm)=5.29 (br.s, NH2), 3.05 (sext., J:7.0, 1H, H-C(6)),
2.55–2.30 (m, 3H), 1.88 (m, 1H), 1.63 (s, 9H tert-Bu), 1.27
(d, J=7.1, Me). 6 (CDCl3): l (ppm)=3.30 (sext., J:7.0,
1H, H-C(6)), 2.92 (br. s, NH2), 2.75 (m, 1H), 2.60 (m, 1H),
2.1 (m, 1H), 1.60 (s, 9H, tert-Bu), 1.22 (d, J=7.1, Me). 7
(CDCl3): l (ppm)=7.50–7.30 (m, 5H), 5.42 (d, J=12.2,
PhCH), 5.38 (d, J=12.2, PhCH), 5.00 (br.s, NH2), 3.01
(sext. J:7.1, H-C(6)), 2.58–2.31 (m, 3H), 1.96–1.82 (m,
1H), 1.26 (d, J=7.1, Me). 9 (CDCl3): l (ppm)=7.36–7.12
(m, 5H), 5.20 (d, J=12.1, 1H, PhCH), 5.16 (d, J=12.1, 1H,
PhCH), 3.26 (br.s, NH2), 3.01 (sext. J:7.0, 1H, H-C(6)),
2.61–2.36 (m, 3H), 1.99–1.82 (m, 1H), 1.27 (d, J=7.1, Me).
10 (CDCl3): l (ppm)=5.11 (s, 2H, PhCH2), 3.58 (t, J:7.6,
1H, OCHCH2), 3.55 (t, J:7.6, 1H, OCHCH2), 3.32 (br.s,
NH2), 3.11 (sext. J:7.0, 1H, H-C(6)), 2.78–2.66 (m, 1H),
2.54–2.35 (m, 2H), 2.12–2.01 (m, 1H), 1.24 (d, J=7.1, Me),
0.91 (t, J:7.8, 1H, CH2CHSiMe3), 0.90 (dd, J=8.2, 6.3,
1H, CH2CHSiMe3), −0.02 (s, SiMe3). 11 (CDCl3): l
(ppm)=10.35 (br.s, NH), 7.61–7.53 (m, 4H), 7.46–7.32 (m,
5H), 3.76 (s, 2H, PhCH2), 3.09–2.95 (m, 2H), 2.91–2.80 (m,
1H), 2.52–2.41 (m, 1H), 1.91–1.79 (m, 1H), 1.59 (s, 9H,
tert-Bu), 1.27 (d, J=7.1, Me). 12 (DMSO-d6): l (ppm)=
11.91 (br.s, NH), 10.30 (br.s, NH), 7.66–7.59 (m, 4H),
7.48–7.33 (m, 5H), 3.61 (s, 2H, PhCH2), 3.10 (br.s, 1H,
H-C(6)), 2.63–2.48 (m, 3H), 1.90–1.82 (m, 1H), 1.15 (d,
J=6.9, Me).
Figure 1. X-Ray structure analysis14 of 11: ORTEP15 presen-
tation (ellipsoids enclose 50% of the electron density).
Acknowledgements
We thank Dr. Stuart Ince (Schering AG) for linguistic
improvements and Dr. Eckhard Ottow (Schering AG)
for his support.
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Data Centre as supplementary publication number CCDC
205961. Copies of the data can be obtained, free of charge,
on application to CCDC, 12 Union Road, Cambridge CB2
1EZ, UK (Fax: +44-1223-336-033 or e-mail: deposit@
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8. Prepared from 2-methylcyclopentanone according to the
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