6860
M. Argese et al. / Tetrahedron 62 (2006) 6855–6861
ꢀ
MeOH (270 mL) to afford 8 (6.2 g; 26%). Mp 255–257 C
we used: (i) injection: 50 mbar, 5 s; (ii) electrolyte: 30 mM
sodium borate buffer at pH 9.3, 0.3 mM EDTA, 20 mM
sodium dodecyl sulfate (SDS), 1% MeOH. For the analyses
of the mixtures containing 6–9 we used: (i) injection:
9
ꢀ
(400 MHz, CDCl ) (see the atom numbers in the ORTEP
ꢂ1
1
(lit. 252 C). IR (KBr) n 1458, 1687 cm
; H NMR
3
view of the parent compound 9) d 2.60 (m, 2H: 5, 6), 2.76
(m, 4H: 4, 7, 5, 6), 3.12 (m, 2H: 4, 7), 3.45 (m, 2H: 3, 8),
5
0 mbar, 3 s; (ii) electrolyte: 50 mM sodium borate buffer
at pH 8.1, 0.3 mM EDTA, 180 mM sodium dodecyl sulfate
SDS), 1% MeOH.
13
3.89 (m, 2H: 3, 8), 4.13 (s, 2H: 9, 10); C NMR
(100 MHz, CDCl ) d 44.5 (3, 8), 47.1 (5, 6), 49.7 (4, 7),
(
3
+
6
9.8 (9, 10), 157.6 (1, 2); MS m/z (ESI) 223 (M+H) , 245
(M+Na) ; Anal. Calcd for C H N O : C, 54.04; H, 6.35;
10 14 4 2
+
4
4
.3. Synthetic methods
N, 25.21. Found: C, 53.95; H, 6.40; N, 25.12.
.3.1. cis-Octahydro-2a,4a,6a,8a-tetraazacyclopent[fg]-
acenaphthylene 1,2-dione (6). A solution of bis-aminals
having the composition described in Table 1, entry 4 (21 g;
4.3.4. trans-Octahydro-2a,4a,6a,8a-tetraazacyclopent-
[fg]acenaphthylene 3,4-dione (9). A solution of bis-aminals
having the composition reported in Table 1, entry 6 (5.5 g;
0.033 mol) in EtOH (80 mL) was treated with MeONa
(0.88 g; 0.0163 mol) and DEO (2.38 g; 0.0163 mol). After
heating at reflux for 8 h under nitrogen atmosphere, the reac-
tion mixture was concentrated to 20 g. The suspension thus
obtained was filtered and the solid was crystallised from
MeOH (10 mL) to afford 9 (0.5 g; 13.8%). Mp 255–
0
.125 mol) in EtOH (160 mL) was treated with MeONa
6.75 g; 0.125 mol) and DEO (36.5 g; 0.25 mol). After 2 h
(
at reflux under nitrogen atmosphere, the mixture was cooled
to 30 C and 37% HCl (12.3 g; 0.125 mol) was dropped in.
ꢀ
The precipitated hydrochloride was filtered, washed with
EtOH (3ꢁ20 mL), dissolved in water (80 mL), and then the
solution was neutralized with Na CO (6.9 g; 0.065 mol)
2
3
ꢀ
ꢂ1
1
and taken to dryness. The residue was boiled with MeOH
55 mL), the suspension was filtered and the clear solution
was left at rt for 24 h. The crystalline precipitate was filtered,
256 C. IR (KBr) n 1433, 1682 cm ; H NMR (400 MHz,
CDCl ) d 2.71 (ddd, 2H, J¼6.5, 8.7, 10.2 Hz: 4, 7), 2.90
(
3
(m, 2H: 5, 6), 3.38 (m, 4H: 4, 7, 5, 6), 3.49 (ddd, 2H,
J¼5.9, 10.2, 11.6 Hz: 3, 8), 4.20 (ddd, 2H, J¼0.7, 6.5,
washed with MeOH (10 mL) and dried to afford 6 (7.5 g;
ꢀ
ꢂ1
13
2
7%). Mp 158–160 C. IR (KBr) n 1429, 1719 cm
;
11.6 Hz: 3, 8), 4.42 (s, 2H: 9, 10); C NMR (100 MHz,
CDCl ) d 44.6 (3, 8), 49.9 (5, 6), 53.3 (4, 7), 71.8 (9, 10),
1
H NMR (400 MHz, CDCl ) d 2.56 (ddd, 2H, J¼2.2, 5.7,
3
3
+
+
1
3
0.3 Hz: 6, 1), 2.73 (m, 2H: 7, 8), 2.95 (m, 4H: 7, 8, 6, 1),
.11 (ddd, 2H, J¼5.7, 10.0, 13.9 Hz: 5, 2), 3.64 (d, 1H,
156.9 (1, 2); MS m/z (ESI) 223 (M+H) , 245 (M+Na) ;
Anal. Calcd for C H N O : C, 54.04; H, 6.35; N, 25.21.
Found: C, 53.88; H, 6.44; N, 24.98.
1
0 14 4 2
J¼4.6 Hz: 9), 4.20 (ddd, 2H, J¼2.2, 6.4, 13.9 Hz: 5, 2),
1
3
5
d 38.0 (5, 2), 48.0 (6, 1), 50.4 (7, 8), 65.4 (10), 74.8 (9),
.17 (d, 1H, J¼4.6 Hz: 10); C NMR (100 MHz, CDCl )
3
4.4. X-ray crystallographic study
+
+
160.0 (4, 3); MS m/z (ESI) 223 (M+H) , 245 (M+Na) ;
Anal. Calcd for C H N O : C, 54.04; H, 6.35; N, 25.21.
Found: C, 54.02; H, 6.39; N, 25.18.
Cell parameters and intensity data for compounds 6, 7, 8 and
9 were obtained on a Siemens P4 diffractometer, using
1
0 14 4 2
˚
graphite monochromated Cu Ka radiation (l¼1.54180 A).
4
.3.2. trans-Octahydro-2a,4a,6a,8a-tetraazacyclopent[fg]-
Cell parameters were determined by least squares fitting of
25 centered reflections. The intensities of three standard re-
flections were measured every 60 min to check the stability
of the diffractometer and the decay of the crystals. Intensity
data were corrected for Lorentz and polarisation effects, an
absorption correction was applied once the structures were
acenaphthylene 1,2-dione (7). The mother liquor obtained
from the filtrate of the hydrochloride used for the preparation
of 6 was evaporated to dryness and the residue was purified
by silica gel chromatography (6:3:1 CHCl /CH OH/25%
3
3
NH OH). The fractions enriched with the desired com-
4
2
0
pound were combined and evaporated to dryness, then the
residue was crystallised three times from methanol to afford
solved by using the Walker and Stuart method.
2
1
Structures were solved using the SIR-97 program and sub-
sequently refined by the full-matrix least squares program
SHELX-97. Given that the solid state structure of com-
ꢀ
737 cm ; H NMR (400 MHz, CDCl ) d 1.48 (d, 1H,
7
1
(1.5 g; 5.4%). Mp 258–260 C. IR (KBr) n 1442,
ꢂ1
1
22
3
J¼6.2 Hz: 9), 2.33 (m, 2H: 6, 1), 2.46 (m, 2H: 7, 8), 3.22
pound 8 was found to be isomorphous and isostructural
with the already published structure, our X-ray data will
9
(
dd, 2H, J¼4.7, 10. 9 Hz: 6, 1), 3.38 (m, 4H: 7, 8, 5, 2),
4
5
8
.22 (d, 1H, J¼6.2 Hz: 10), 4.28 (dd, 2H, J¼3.1, 14.1 Hz:
not be published. The hydrogen atoms of compounds 6, 7
and 9 were introduced in calculated position and their coor-
dinates refined in agreement with those of the linked atoms.
All the nonhydrogen atoms were refined anisotropically.
Atomic scattering factors and anomalous dispersion correc-
1
3
, 2); C NMR (100 MHz, CDCl ) d 41.2 (5, 2), 50.8 (7,
3
), 52.3 (6, 1), 67.0 (10), 92.8 (9), 157.5 (4, 3); MS m/z
+
+
(ESI) 223 (M+H) , 245 (M+Na) ; Anal. Calcd for
C H N O : C, 54.04; H, 6.35; N, 25.21. Found: C, 53.97;
H, 6.41; N, 25.15.
1
0 14 4 2
2
3
tions for all the atoms were taken from the literature. The
molecular plots were produced by the ORTEP3 program
2
4
4.3.3. cis-Octahydro-2a,4a,6a,8a-tetraazacyclopent[fg]-
acenaphthylene 3,4-dione (8). A solution of bis-aminals
having the composition reported in Table 1, entry 6 (30 g;
and the ORTEP views of compounds 6, 7 and 9, along with
a PLUTO view of compound 8, are detailed in Figures 1–4.
Crystal parameters and structure refinement data for 6, 7 and
9 are resumed in Table 5.
0
(
.178 mol) in EtOH (225 mL) was treated with DEO
13 g; 0.089 mol) and heated at reflux for 18 h under nitro-
gen atmosphere. After addition of further DEO (2.6 g;
.018 mol) and heating for 4 h at reflux, the solid, which
Crystallographic data (excluding structure factors) for the
structures in this paper have been deposited with the Cam-
bridge Structural Data Centre as supplementary publication
numbers CCDC 292972, CCDC 292973 and CCDC 292974.
0
spontaneously precipitated was filtered after cooling the
suspension to rt. The product was crystallised from