Aminomethylation of N-methylmorpholinium 6-amino-4-aryl-3,5-dicyano-1,4- dihydropyridine-2-selenolates as an approach to the preparation of 3,5,7,11-tetraazatricyclo[7.3.1.02,7]tridec-2-ene-8-selenone derivatives

Article abstract of DOI:10.1007/s11172-013-0201-3

A reaction of N-methylmorpholinium 6-amino-4-aryl-3,5-dicyano-1,4- dihydropyridine- 2-selenolates with primary amines and excess of formaldehyde leads to 3,5,7,11-tetra- azatricyclo[7.3.1.02,7]tridec-2-ene-8-selenone derivatives. The same compounds were obtained by a multicomponent cascade cyclocondensation of benzaldehyde, cyanoselenoacetamide, primary amine, and excess of formaldehyde.

Full text of DOI:10.1007/s11172-013-0201-3

Russian Chemical Bulletin, International Edition, Vol. 62, No. 6, pp. 1401—1404, June, 2013
1401
Aminomethylation of Nꢀmethylmorpholinium 6ꢀaminoꢀ4ꢀarylꢀ3,5ꢀdicyanoꢀ1,4ꢀ
dihydropyridineꢀ2ꢀselenolates as an approach to the preparation
of 3,5,7,11ꢀtetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ8ꢀselenone derivatives
K. A. Frolov, V. V. Dotsenko, and S. G. Krivokolysko
ChemEx Laboratory, V. Dal´ EastꢀUkrainian National University,
20a kv. Molodezhnyi, 91034 Lugansk, Ukraine.
Eꢀmail: ka.frolov@inbox.ru
A reaction of Nꢀmethylmorpholinium 6ꢀaminoꢀ4ꢀarylꢀ3,5ꢀdicyanoꢀ1,4ꢀdihydropyridineꢀ
2ꢀselenolates with primary amines and excess of formaldehyde leads to 3,5,7,11ꢀtetraꢀ
azatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ8ꢀselenone derivatives. The same compounds were obtained
by a multicomponent cascade cyclocondensation of benzaldehyde, cyanoselenoacetamide,
primary amine, and excess of formaldehyde.
Key words: Nꢀmethylmorpholinium 6ꢀaminoꢀ4ꢀarylꢀ3,5ꢀdicyanoꢀ1,4ꢀdihydropyridineꢀ2ꢀ
selenolate, multicomponent cyclocondensation, cyanoselenoacetamide, Mannich reaction,
3,5,7,11ꢀtetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ8ꢀselenone.
Pyridineꢀ2(1H)ꢀchalcogenones are an interesting class
of heterocyclic compounds with a wide range of practicalꢀ
ly useful properties and a possibility of chemical converꢀ
sions, which lead to various new heterocyclic systems.1,2
In continuation of our studies in the field of aminomeꢀ
thylation of such compounds,3—18 we have found that
treatment of Nꢀmethylmorpholinium 6ꢀaminoꢀ4ꢀarylꢀ3,5ꢀ
dicyanoꢀ1,4ꢀdihydropyridineꢀ2ꢀselenolates 1a—c with priꢀ
mary amines in the presence of an excess of the 37% aqueꢀ
ous formaldehyde resulted in 3,5,7,11ꢀtetraazatricycloꢀ
[7.3.1.02,7]tridecꢀ2ꢀeneꢀ8ꢀselenone derivatives 2a—h in
12—55% yields (Scheme 1, method A).
An alternative approach to the preparation of the tarꢀ
get structures 2 consisted in the multicomponent cycloꢀ
condensation of benzaldehyde (3), cyanoselenoacetamide
(4), primary amine, and formaldehyde. Thus, the reaction
of benzaldehyde with cyanoselenoacetamide 4 in the presꢀ
ence of morpholine and subsequent treatment with primary
Scheme 1
1: R = 2ꢀFC6H4 (a), 2ꢀMeOC6H4 (b), 2ꢀEtOC6H4 (c), Ph (d, e); B = Nꢀmethylmorpholine (a—d), morpholine (e)
2
a
b
R
Ph
Ph
R´
Ph
Me
2
c
d
R
R´
2ꢀMeOC6H4 4ꢀMeC6H4
2ꢀMeOC6H4 Ph
2
e
f
R
R´
2ꢀMeOC6H4 CH2Ph
2ꢀMeOC6H4 Me
2
g
h
R
R´
2ꢀEtOC6H4 4ꢀMeC6H4
2ꢀEtOC6H4 CH2Ph
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1401—1404, June, 2013.
1066ꢀ5285/13/6206ꢀ1401 © 2013 Springer Science+Business Media, Inc.

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Frolov et al.
amines and excess of 37% aqueous formaldehyde resulted
in compounds 2a,b in 14 and 39% yields. The reaction
possibly proceeds through the consecutive formation of
unsaturated selenoamide 5 and selenolate 1e. The latter
further undergoes a cascade aminomethylation to form
3,5,7,11ꢀtetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ8ꢀseleꢀ
nones 2 (see Scheme 1, method B).
Earlier,19 we have shown that the reaction of benzꢀ
aldehyde with cyanoselenoacetamide, primary amines, and
excess of formaldehyde catalyzed by Nꢀmethylmorpholine
led to pyrimido[4,3ꢀb][1,3,5]selenadiazine derivatives.
Supposedly, the alternative direction of the reaction obꢀ
served in this case is due to the higher bacisity of morphoꢀ
line as compared to that of Nꢀmethylmorpholine. Apparꢀ
ently, 2ꢀcyanoꢀ3ꢀphenylpropꢀ2ꢀeneselenoamide 5 formed
in the first step reacts in situ in the presence of morpholine
with the second equivalent of cyanoselenoacetamide to
form selenolate 1e. Subsequent aminomethylation proꢀ
ceeds similarly to that in method A.
are converted to compounds 2. According to pathway b,
the initial aminomethylation takes place at the nitrogen
atoms with the formation of pyridotriazines 8, which in
the course of subsequent Cꢀaminomethylation through the
intermediate 9 are converted to the final products 2.
Both pathways for the formation of tetraazatricycloꢀ
tridecene skeleton of compounds 2 can proceed simultaꢀ
neously. Supposedly, the construction of the 3,7ꢀdiꢀ
azabicyclo[3.3.1]nonane fragment begins from the
C(5)ꢀaminomethylation of dihydropyridine ring. As it was
shown earlier20—22 using related pyridineꢀ2ꢀthiolates as
an example, the presence of an electronꢀwithdrawing subꢀ
stituent at position C(5) was a determining factor for the
reaction of C(3),C(5)ꢀdiaminomethylation to proceed. In
the absence of an electronꢀwithdrawing substituent, pyriꢀ
dineꢀ2ꢀthiolates play the role of typical S,Nꢀbinucleophiles
and do not give the Cꢀaminomethylation products.8
The structure of 3,5,7,11ꢀtetraazatricyclo[7.3.1.02,7]ꢀ
tridecꢀ2ꢀeneꢀ8ꢀselenones 2 was confirmed by spectroꢀ
scopic studies. The IR spectra of the compounds synꢀ
thesized exhibit absorption bands at 2248—2255 and
1646—1655 cm–1, which indicate the presence of the unꢀ
conjugated nitrile group and the C=N fragment, respecꢀ
tively. The 1H NMR spectra of compounds 2 are characꢀ
terized by the presence of four sets of signals, which correꢀ
spond to four methylene groups. The signals for the proꢀ
tons C(4)H2 and C(6)H2 of the tetrahydroꢀ1,3,5ꢀtriazine
ring were found as two pairs of doublets in the region
 4.23—5.18 (2J = 17.0—17.4 Hz) and 5.07—6.12
(2J = 12.7—13.7 Hz), respectively. Protons C(10)H2 and
C(12)H2 resonate at  2.89—4.29 as two pairs of doublets
with 2J = 10.5—11.8 Hz or as multiplets resulting from the
partial overlap of the signals. The 1H NMR spectra of
compounds 2 also exhibit signals for proton C(13)H as
a singlet at  4.21—4.77 and three sets of signals for the
substituents: one from C(13)Ar and two from the primary
amine. The 1H NMR spectra of compounds 2 agree with
the data obtained for the related 8ꢀthioxoꢀ3,5,7,11ꢀ
tetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀenes,4,5 whose strucꢀ
ture is unambiguously confirmed by Xꢀray crystalloꢀ
graphy.5
Two plausible pathways can be suggested for the amiꢀ
nomethylation of compounds 1 (Scheme 2, a and b).
Pathway a supposes an initial formation of products of
Cꢀaminomethylation of 6, which through the bispidine
intermediate 7 and subsequent N,N´ꢀdiaminomethylation
Scheme 2
In conclusion, Nꢀmethylmorpholinium 6ꢀaminoꢀ4ꢀ
arylꢀ3,5ꢀdicyanoꢀ1,4ꢀdihydropyridineꢀ2ꢀselenolates under
the Mannich reaction conditions form 3,5,7,11ꢀtetraꢀ
azatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ8ꢀselenones. Similar
result was obtained by the morpholineꢀcatalyzed multiꢀ
component cascade cyclocondensation of benzaldehyde,
cyanoselenoacetamide, primary amine, and formaldehyde.
Experimental
1
H NMR spectra were recorded on a Bruker Avance II 400
spectrometer (399.97 MHz) in DMSOꢀd6, using Me4Si as an
internal standard. IR spectra were recorded on a IKSꢀ29 spectroꢀ
photometer (in Nujol), elemental analysis was performed on

Tetraazatricyclo[7.3.1.02,7]trideceneselenones
Russ.Chem.Bull., Int.Ed., Vol. 62, No. 6, June, 2013
1403
a Carlo Erba Strumentazione Elemental Analyzer 1106 instruꢀ
ment. The individuality of the samples obtained was controlled
by TLC on Silufol UVꢀ254 plates, using a mixture of acetꢀ
one—hexane (1 : 1) as an eluent and the iodine vapors or a UV
detector as a visualizing agent. Melting points of compounds
were determined on a Kofler heating stage and were not correctꢀ
ed. The preparation and the properties of selenolates 1b 23 and
1d 24 were described earlier. Selenolates 1a,c were synthesized
according to the known procedure25 by the reaction of aldehydes
with 2 equiv. of cyanoselenoacetamide 4 in the presence of
Nꢀmethylmorpholine. Cyanoselenoacetamide 4 was obtained by
passing H2Se through the solution of malononitrile in diethyl
ether.26 All the syntheses were carried out under argon.
NꢀMethylmorpholinium 6ꢀaminoꢀ3,5ꢀdicyanoꢀ4ꢀ(2ꢀfluoroꢀ
phenyl)ꢀ1,4ꢀdihydropyridineꢀ2ꢀselenolate (1a). The yield was
66%, m.p. 155—157 C. Found (%): C, 54.21; H, 5.09; N, 13.31.
C13H8FN4Se•C5H12NO. Calculated (%): C, 54.42; H, 5.05;
N, 13.36. IR, /cm–1: 3415, 3315, 3270 (NH2, NH); 2175
(2 CN); 1650 (C=C). 1H NMR, : 2.35 (s, 3 H, NMe); 2.51—2.65
(m, 4 H, N(CH2)2); 3.59—3.71 (m, 4 H, O(CH2)2); 4.64 (s, 1 H,
C(4)H); 5.84 (br.s, 2 H, NH2); 7.05—7.31 (m, 4 H, HAr); 9.34
(s, 1 H, NH).
NꢀMethylmorpholinium 6ꢀaminoꢀ3,5ꢀdicyanoꢀ4ꢀ(2ꢀethoxyꢀ
phenyl)ꢀ1,4ꢀdihydropyridineꢀ2ꢀselenolate (1c). The yield was
63%, m.p. 120—122 C. Found (%): C, 53.73; H, 5.68; N, 15.47.
C15H13N4OSe•C5H12NO. Calculated (%): C, 53.81; H, 5.60;
N, 15.69. IR, /cm–1: 3382, 3310 (NH2, NH); 2190 (2 CN);
1620 (C=C). 1H NMR, : 1.44 (t, 3 H, OCH2CH3, 3J = 6.9 Hz);
2.26 (s, 3 H, NMe); 2.38—2.47 (m, 4 H, N(CH2)2); 3.56—3.61
(m, 4 H, O(CH2)2); 4.07 (q, 2 H, OCH2CH3, 3J = 6.9 Hz); 4.72
(s, 1 H, C(4)H); 5.69 (br.s, 2 H, NH2); 6.88—7.49 (m, 4 H,
HAr); 9.07 (s, 1 H, NH).
Tetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ8ꢀselenones 2.
Method A. A mixture of the corresponding selenolate 1 (2.3 mmol),
a primary amine (6 mmol), and excess of the 37% aqueous formꢀ
aldehyde (54 mmol, 4.0 mL) in EtOH (40 mL) was stirred for
10 min under argon, then refluxed until the starting reagents
were dissolved (~2—3 min), rapidly filtered through a paper
filter, and allowed to stand for 24 h at room temperature under
argon. A precipitate formed was filtered off, washed with EtOH
and hexane.
Method B. A mixture of benzaldehyde 3 (0.14 mL, 1.36 mmol),
freshly prepared cyanoselenoacetamide 4 (0.20 g, 1.36 mmol),
and morpholine (1 drop) in ethanol (15 mL) was stirred under
argon at 20 C. After 10 min, the corresponding primary amine
(2.9 mmol) and excess of 37% aq. formaldehyde (2.0 mL,
27 mmol) were added, and the mixture was stirred for another
10 min. Then, the solution obtained was refluxed for 2—3 min,
filtered through a folded paper filter, and allowed to stand for
24 h at room temperature under argon. A precipitate formed was
filtered off and washed with EtOH and hexane.
5,11ꢀDimethylꢀ13ꢀphenylꢀ8ꢀselenoxoꢀ3,5,7,11ꢀtetraazatriꢀ
cyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ1,9ꢀdicarbonitrile (2b). The yield
was 0.22 g (23%, method A), 0.22 g (39%, method B), m.p.
200—202 C (EtOH). Found (%): C, 55.31; H, 4.94; N, 20.13.
C19H20N6Se. Calculated (%): C, 55.48; H, 4.90; N, 20.43. IR,
/cm–1: 2255 (2 CN); 1655 (C=N). 1H NMR, : 2.41, 2.49
(both s, 3 H each, 2 Me); 2.89, 3.09, 3.31, 3.35 (all d, 1 H each,
2
C(10)H2, C(12)H2, J = 10.8 Hz); 4.21 (s, 1 H, C(13)H); 4.23,
4.46 (both d, 1 H each, C(4)H2, 2J = 17.2 Hz); 5.07, 5.54 (both
d, 1 H each, C(6)H2, 2J = 12.7 Hz); 7.25—7.44 (m, 5 H, Ph).
13ꢀ(2ꢀMethoxyphenyl)ꢀ5,11ꢀdi(4ꢀmethylphenyl)ꢀ8ꢀselenoxoꢀ
3,5,7,11ꢀtetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ1,9ꢀdicarboꢀ
nitrile (2c). The yield was 0.67 g (49%, method A). Spectroꢀ
scopic characteristics of the sample obtained were identical to
those given in the work.17
13ꢀ(2ꢀMethoxyphenyl)ꢀ5,11ꢀdiphenylꢀ8ꢀselenoxoꢀ3,5,7,11ꢀ
tetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ1,9ꢀdicarbonitrile (2d).
The yield was 0.47 g (36%, method A), m.p. 212—214 C (EtOH).
Found (%): C, 63.49; H, 4.68; N, 14.69. C30H26N6OSe. Calcuꢀ
lated (%): C, 63.71; H, 4.63; N, 14.86. IR, /cm–1: 2250
(2 CN); 1655 (C=N). 1H NMR, : 3.74, 4.26 (both d, 1 H each,
2
C(10)H2 or C(12)H2, J = 11.6 Hz); 3.85 (s, 3 H, OMe); 3.88,
4.06 (both d, 1 H each, C(12)H2 or C(10)H2, 2J = 11.8 Hz);
4.77 (s, 1 H, C(13)H); 4.88, 5.17 (both d, 1 H each, C(4)H2, 2J =
= 17.4 Hz); 5.41, 6.12 (both d, 1 H each, C(6)H2, 2J = 13.4 Hz);
6.58—7.33 (m, 14 H, HAr).
5,11ꢀDibenzylꢀ13ꢀ(2ꢀmethoxyphenyl)ꢀ8ꢀselenoxoꢀ3,5,7,11ꢀ
tetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ1,9ꢀdicarbonitrile (2e).
The yield was 0.69 g (51%, method A), m.p. 190—192 C (EtOH).
Found (%): C, 64.59; H, 5.12; N, 14.96. C32H30N6OSe. Calcuꢀ
lated (%): C, 64.75; H, 5.09; N, 14.16. IR, /cm–1: 2252 (2 CN);
1650 (C=N). 1H NMR, : 2.94, 3.12, 3.52, 3.78 (all d, 1 H each,
2
C(10)H2, C(12)H2, J = 10.7 Hz); 3.79—3.84 (m, 4 H, overlap
of two signals CH2Ph); 3.89 (s, 3 H, OMe); 4.28, 4.44 (both d,
2
1 H each, C(4)H2, J = 17.2 Hz); 4.49 (s, 1 H, C(13)H); 5.24,
5.47 (both d, 1 H each, C(6)H2, 2J = 12.7 Hz); 6.99—7.42
(m, 14 H, HAr).
13ꢀ(2ꢀMethoxyphenyl)ꢀ5,11ꢀdimethylꢀ8ꢀselenoxoꢀ3,5,7,11ꢀ
tetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ1,9ꢀdicarbonitrile (2f).
The yield was 0.56 g (55%, method A). Spectroscopic characterꢀ
istics of the sample obtained were identical to those given in the
work.17
13ꢀ(2ꢀEthoxyphenyl)ꢀ5,11ꢀdi(4ꢀmethylphenyl)ꢀ8ꢀselenoxoꢀ
3,5,7,11ꢀtetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ1,9ꢀdicarboꢀ
nitrile (2g). The yield was 0.56 g (40%, method A), m.p.
191—193 C (BuOH). Found (%): C, 65.00; H, 5.38; N, 13.67.
C33H32N6OSe. Calculated (%): C, 65.23; H, 5.31; N, 13.83. IR,
1
/cm–1: 2248 (2 CN); 1655 (C=N). H NMR, : 1.48 (t, 3 H,
3
OCH2CH3, J = 6.9 Hz); 2.15, 2.25 (both s, 3 H each, 2 Me);
3.57 (d, 1 H, C(12)H2 or C(10)H2, 2J = 11.7 Hz); 3.71, 3.93
(both d, 1 H each, C(10)H2 or C(12)H2, 2J = 11.5 Hz); 4.07—4.16
(m, 3 H, overlap of two signals C(12)H or C(10)H and
OCH2CH3); 4.64 (s, 1 H, C(13)H); 4.86, 5.05 (both d, 1 H each,
C(4)H2, 2J = 17.3 Hz); 5.66, 5.89 (both d, 1 H each, C(6)H2,
2J = 13.6 Hz); 6.61—7.30 (m, 12 H, HAr).
5,11,13ꢀTriphenylꢀ8ꢀselenoxoꢀ3,5,7,11ꢀtetraazatricycloꢀ
[7.3.1.02,7]tridecꢀ2ꢀeneꢀ1,9ꢀdicarbonitrile (2a). The yield
was 0.15 g (12%, method A), 0.10 g (14%, method B), m.p.
218—220 C (DMF). Found (%): C, 64.86; H, 4.54; N, 15.51.
C29H24N6Se. Calculated (%): C, 65.04; H, 4.52; N, 15.69. IR,
/cm–1: 2250 (2 CN); 1655 (C=N). 1H NMR, : 3.68, 3.84,
4.07, 4.29 (all d, 1 H each, C(10)H2, C(12)H2, 2J = 11.7 Hz);
4.45 (s, 1 H, C(13)H); 4.85, 5.18 (both d, 1 H each, C(4)H2,
2J = 17.1 Hz); 5.41, 6.07 (both d, 1 H each, C(6)H2, 2J = 13.7 Hz);
6.80—7.34 (m, 15 H, 3 Ph).
5,11ꢀDibenzylꢀ13ꢀ(2ꢀethoxyphenyl)ꢀ8ꢀselenoxoꢀ3,5,7,11ꢀ
tetraazatricyclo[7.3.1.02,7]tridecꢀ2ꢀeneꢀ1,9ꢀdicarbonitrile (2h).
The yield was 0.52 g (37%, method A), m.p. 204—206 C (EtOH).
Found (%): C, 65.04; H, 5.35; N, 13.55. C33H32N6OSe. Calcuꢀ
lated (%): C, 65.23; H, 5.31; N, 13.83. IR, /cm–1: 2250 (2 CN);
1650 (C=N). 1H NMR, : 1.50 (t, 3 H, OCH2CH3, 3J = 6.9 Hz);

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Russ.Chem.Bull., Int.Ed., Vol. 62, No. 6, June, 2013
Frolov et al.
2.91, 3.52 (both d, 1 H each, C(12)H2 or C(10)H2, 2J = 10.9 Hz);
3.11, 3.55 (both d, 1 H each, C(10)H2 or C(12)H2, 2J = 10.5 Hz);
3.75—3.84 (m, 4 H, overlap of two signals CH2Ph); 4.05—4.18
(m, 2 H, OCH2CH3); 4.28, 4.44 (both d, 1 H each, C(4)H2, 2J =
= 17.0 Hz); 4.49 (s, 1 H, C(13)H); 5.26, 5.44 (both d, 1 H each,
C(6)H2, 2J = 12.9 Hz); 7.01—7.33 (m, 14 H, HAr).
13. J. Liebscher, H. Hartmann, DD Pat. 126309; Chem. Abstr.,
1977, 88, 62425.
14. K. Shimada, K. Aikawa, T. Fujita, M. Sato, K. Goto,
S. Aoyagi, Y. Takikawa, S. Kabuto, Bull. Chem. Soc. Jpn,
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S. Kabuto, Chem. Lett., 1997, 8, 701.
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in revised form February 5, 2013