One-step synthesis of substituted 2-amino-4H-chromenes and 2-amino-4H-benzo[f]chromenes. Molecular and crystal structure of 2-amino-3-cyano-6-hydroxy-4-phenyl-4H-benzo[f]chromene

Article abstract of DOI:10.1023/A:1022135402451

Substituted 2-aminochromenes were synthesized by three-component condensation of aromatic aldehydes, derivatives of cyanoacetic acid, and phenols or naphthols. The molecular and crystal structure of 2-amino-3-cyano-6-hydroxy-4-phenyl-4H-benzo[f]chromene w

Full text of DOI:10.1023/A:1022135402451

2238
Russian Chemical Bulletin, International Edition, Vol. 51, No. 12, pp. 2238—2243, December, 2002
Oneꢀstep synthesis of substituted 2ꢀaminoꢀ4Hꢀchromenes
and 2ꢀaminoꢀ4Hꢀbenzo[ f ]chromenes. Molecular and crystal structure
of 2ꢀaminoꢀ3ꢀcyanoꢀ6ꢀhydroxyꢀ4ꢀphenylꢀ4Hꢀbenzo[ f ]chromene
a
b
A. M. Shestopalov,a Yu. M. Emelianova, and V. N. Nesterov
ꢀ
aN. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences,
47 Leninsky prosp., 119991 Moscow, Russian Federation.
Fax: +7 (095) 135 5328. Eꢀmail: shchem@dol.ru
bA. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences,
28 ul. Vavilova, 119991 Moscow, Russian Federation.
Fax: +7 (095) 135 5085
Substituted 2ꢀaminochromenes were synthesized by threeꢀcomponent condensation of
aromatic aldehydes, derivatives of cyanoacetic acid, and phenols or naphthols. The molecular
and crystal structure of 2ꢀaminoꢀ3ꢀcyanoꢀ6ꢀhydroxyꢀ4ꢀphenylꢀ4Hꢀbenzo[f]chromene was esꢀ
tablished by Xꢀray diffraction analysis.
Key words: pyran, phenol, naphthol, chromene, benzochromene, Xꢀray diffraction analyꢀ
sis, molecular structure, crystal structure.
Considerable interest in fused 2ꢀaminoꢀ4Hꢀpyrans
stems from the possibility of their use as drugs, pesticides,
analogs of natural compounds, dyes, and other materials
of practical importance.1—7 Substituted 2ꢀaminoꢀ4Hꢀ
benzochromenes were proposed for the treatment of imꢀ
mune diseases and diabetic complications resulted from
an increase in permeability of blood vessels and a change
in blood pressure.2 Some of these compounds exhibit acꢀ
tivity preventing cell growth and multiplication by interꢀ
fering with one of the phases of the cell cycle.3 Chromenꢀ
4ꢀone derivatives or their salts can be used as immunoꢀ
modulators and for the prophylaxis and treatment of difꢀ
ferent diseases of connective tissues, diabetes, psoriasis,
pernicious anemia, ulcerous colitis, and chronic hepaꢀ
titis.4 In addition, many compounds containing the
enaminonitrile fragment are used as convenient synthons
in the organic synthesis.1,5—7
Previously,8—11 2ꢀaminoꢀ4Hꢀchromenes (1—3,
Scheme 1) have been synthesized in two steps. The first
step consisted in preparing and isolating arylmethyleneꢀ
malononitrile. The second step involved the reaction of
this compound with the corresponding phenol or naphꢀ
thol. However, the preliminary synthesis (and isolation of
arylmethylenemalononitriles) is sometimes impossible.12
In addition, this process is associated with a particular
danger because the resulting compounds are strong
lacrimators and are similar in toxicity to CS, which is a
component of war gases.7 When considering methods for
the synthesis of substituted chromenes, we got interested
in the study13 in which 2ꢀaminoꢀ4ꢀarylꢀ3ꢀcyanoꢀ4Hꢀ
(benzo)chromenes were prepared by threeꢀcomponent
condensation of aromatic aldehydes, malononitrile, and
resorcinol or βꢀnaphthol. In the cited study,13 the prodꢀ
uct of the reaction of benzaldehyde, malononitrile, and
resorcinol was assigned the structure of 2ꢀaminoꢀ3ꢀcyanoꢀ
5ꢀhydroxyꢀ4ꢀphenylꢀ4Hꢀchromene without reporting the
1
interpretation of the H NMR spectra, and, hence, this
assumption was not confirmed.
The present study had two main purposes. One goal
was to examine the behavior of phenol and naphthol deꢀ
rivatives, which differ from those described earlier,13 in
threeꢀcomponent condensation. Another aim was to study
the structures of the resulting products in detail.
Threeꢀcomponent condensation was carried out by
adding a catalytic amount of triethylamine to an ethanolic
solution of aromatic aldehyde 4, malononitrile 5a (or
cyanoacetic ester 5b), and the corresponding phenol 6 (or
naphthalenediol 7—9) taken in an equimolar ratio and
bringing the reaction mixture to boiling. Under these conꢀ
ditions, the reaction proceeded regioselectively to give
the final (benzo)chromenes 1—3 in high yields (see the
Experimental section).
The use of naphthalenediols attracted our attention
because the reactions of some of these compound with
double amounts of aromatic aldehyde 4 and malononitrile
5a can afford naphthopyrans 10 and 11, which are of
interest for further investigation.
An earlier attempt9 to synthesize benzochromenes
from 2,7ꢀnaphthalenediol and arylmethylenemalonoꢀ
nitriles has failed. We succeeded in preparing 2ꢀaminoꢀ
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2079—2083, December, 2002.
1066ꢀ5285/02/5112ꢀ2238 $27.00 © 2002 Plenum Publishing Corporation

Oneꢀstep synthesis of 2ꢀaminoꢀ4Hꢀchromenes
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 12, December, 2002 2239
Scheme 1
Ar = 4ꢀMeOCOC6H4 (1a,e, 4a), 2,4ꢀF2C6H3 (1b,c,f, 4b),
3ꢀBrC6H4 (1d, 4c), 3ꢀC5H4N (1g, 4d), Ph (2a, 4e),
4ꢀClC6H4 (2b, 4f, 11), 3ꢀC4H3S (3, 4g, 10a), 4ꢀFC6H4 (4h, 10b);
R = OH (1a—c, 6a), NH2 (1d—g, 6b);
Z = CN (1a,b,d—g, 5a), COOEt (1c, 5b)
4ꢀarylꢀ3ꢀcyanoꢀ6ꢀhydroxyꢀ4Hꢀbenzo[ f ]chromenes 2a,b
(Ar = Ph or 4ꢀClC6H4) by threeꢀcomponent condensaꢀ
tion. In addition, we found that the reaction of pꢀchloroꢀ
benzaldehyde, malononitrile, and 2,7ꢀnaphthalenediol
afforded only benzochromene 2b regardless of the reagent
ratio (1 : 1 : 1 or 2 : 2 : 1), whereas threeꢀcomponent
condensation with the use of 2,3ꢀnaphthalenediol gave
benzochromene 3 and pyranobenzochromenes 10a,b.
The addition of double amounts of 4ꢀClC6H4CHO
and malononitrile to 1,5ꢀnaphthalenediol yielded chroꢀ
menochromene 11.
All the compounds were synthesized as stable colorꢀ
less powders, which can be recrystallized from EtOH or
MeCN. Their structures were confirmed by spectroscopic
methods and elemental analysis (see the Experimental
section).
1
In the H NMR spectra of compounds 1a,b,d,e, the
signals for the H(5), H(6), and H(8) protons are wellꢀ
3
resolved (δ, J/Hz): 6.59—6.78 (d, H(5) J = 7.8—10.5);
3
4
6.27—6.48 (dd, H(6), J = 7.8—10.5, J = 0.6—1.4);
4
6.22—6.42 (d, H(8), J = 0.6—1.1). In the spectra of
compounds 1f,g, the signals for the H(5) and H(6) proꢀ

2240
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 12, December, 2002
Shestopalov et al.
N(1S)
C(1S)
C(18)
C(2S)
C(19)
C(20)
C(17)
C(16)
O(2)
C(9)
C(15)
C(8)
C(7)
C(4)
N(2)
C(1)
C(6)
C(5)
C(10)
C(2)
C(3)
C(11)
C(18)
C(14)
N(1)
O(1)
C(13)
Fig. 1. Overall view of the 2ꢀaminoꢀ3ꢀcyanoꢀ6ꢀhydroxyꢀ4ꢀphenylꢀ4Hꢀbenzo[ f ]chromene molecule (2a) and the acetonitrile molꢀ
ecule of solvation.
3
tons are observed as two doublets (δ 6.28—6.61, J =
8.1—8.8 Hz) and the signals for the H(8) protons are
observed as singlets (δ 6.24). The assignment of the sigꢀ
nals was made based on the NMR spectroscopic data for
substituted phenols,14 which was allowable due to the
nonaromaticity of the pyran ring. The results of our study
provide evidence in favor of the 7ꢀhydroxyꢀ and 7ꢀaminoꢀ
4Hꢀchromene structures rather than the 5ꢀhydroxyꢀ and
5ꢀaminoꢀ4Hꢀchromene structures, which have been erꢀ
roneously proposed previously.13
along the O(1)...C(4) and C(3)...C(5) lines are rather
small (6.4 and 8.4°, respectively). The dihedral angle beꢀ
tween the naphthalene bicycle and the planar fragment of
the heterocycle is 2.3°, which indicates that the tricyclic
moiety of the molecule is flattened. The pseudoaxial pheꢀ
nyl substituent is virtually perpendicular to the plaꢀ
nar fragment of the pyran ring (the dihedral angle beꢀ
Table 1. Bond lengths (d) in 2ꢀaminoꢀ3ꢀcyanoꢀ6ꢀhydroxyꢀ4ꢀ
phenylꢀ4Hꢀbenzo[ f ]chromene (2a)
The structure of 2ꢀaminoꢀ3ꢀcyanoꢀ6ꢀhydroxyꢀ4ꢀpheꢀ
nylꢀ4Hꢀbenzo[ f ]chromene 2a obtained as a solvate with
acetonitrile was unambiguously established by Xꢀray difꢀ
fraction analysis. Figure 1 shows the overall view of molꢀ
ecule 2a and the acetonitrile molecule of solvation. The
bond lengths and bond angles are given in Tables 1 and 2,
respectively (the atomic numbering scheme used in the
tables does not correspond to the IUPAC rules accepted
in the text of the paper).
Unlike substituted 4Hꢀpyrans studied previously,8,15,16
including 2ꢀaminoꢀ3ꢀethoxycarbonylꢀ4ꢀ(2ꢀfluoropheꢀ
nyl)ꢀ4Hꢀbenzo[ f ]chromene,8 which have a flattened boat
conformation of the heterocycle, the pyran ring in molꢀ
ecule 2a has a sofa conformation with the C(4) atom
deviating from the plane through the remaining five atꢀ
oms of the ring (coplanar to within 0.014 Å) by 0.129 Å
(the O(1) atom is strictly in the plane). The folding angles
Bond
d/Å
Bond
d/Å
O(1)—C(2)
O(1)—C(14)
O(2)—C(8)
N(1)—C(2)
N(2)—C(1)
1.356(2)
1.398(2)
1.365(3)
1.350(3)
1.146(3)
C(7)—C(8)
C(8)—C(9)
C(9)—C(10)
1.370(3)
1.400(3)
1.359(3)
C(10)—C(11) 1.418(3)
C(11)—C(12) 1.416(3)
C(12)—C(13) 1.358(3)
C(13)—C(14) 1.406(3)
C(15)—C(16) 1.398(3)
C(15)—C(20) 1.388(3)
C(16)—C(17) 1.386(3)
C(17)—C(18) 1.381(3)
C(18)—C(20) 1.384(4)
C(19)—C(20) 1.393(3)
C(1S)—C(2S) 1.453(5)
N(1S)—C(1S) 1.129(4)
C(1)—C(3)
C(2)—C(3)
C(3)—C(4)
C(4)—C(5)
C(4)—C(15)
C(5)—C(14)
C(5)—C(6)
C(6)—C(7)
C(6)—C(11)
1.420(3)
1.356(3)
1.518(3)
1.521(3)
1.535(3)
1.369(3)
1.436(3)
1.411(3)
1.432(3)

Oneꢀstep synthesis of 2ꢀaminoꢀ4Hꢀchromenes
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 12, December, 2002 2241
Table 2. Bond angles (ω) in 2ꢀaminoꢀ3ꢀcyanoꢀ6ꢀhydroxyꢀ4ꢀpheꢀ
nylꢀ4Hꢀbenzo[ f ]chromene (2a)
affords 7ꢀhydroxyꢀ or 7ꢀaminochromenes 1 rather than
5ꢀhydroxychromenes.13 Second, 2,7ꢀdihydroxynaphthaꢀ
lene reacts at position 1, which was confirmed by the
Angle
ω/deg
Angle
ω/deg
120.8(2)
results of Xꢀray diffraction analysis.
C(2)—O(1)—C(14) 118.5(2) C(7)—C(8)—С(9)
Experimental
N(2)—C(1)—C(3) 179.3(2) C(10)—C(9)—C(8) 120.0(2)
N(1)—C(2)—O(1) 109.9(2) C(9)—C(10)—C(11) 121.1(2)
N(1)—C(2)—C(3) 127.2(2) C(12)—C(11)—C(10) 121.6(2)
C(3)—C(2)—O(1) 122.8(2) C(12)—C(11)—C(6) 119.5(2)
C(2)—C(3)—C(1) 118.0(2) C(10)—C(11)—C(6) 119.0(2)
C(2)—C(3)—C(4) 123.5(2) C(13)—C(12)—C(11) 120.5(2)
C(1)—C(3)—C(4) 118.3(2) C(12)—C(13)—C(14) 119.5(2)
C(3)—C(4)—C(5) 109.4(2) C(5)—C(14)—O(1) 123.3(2)
C(3)—C(4)—C(15) 110.3(2) C(5)—C(14)—C(13) 123.6(2)
C(5)—C(4)—C(15) 111.7(1) O(1)—C(14)—C(13) 113.0(2)
C(14)—C(5)—C(4) 121.6(2) C(20)—C(15)—C(16) 119.3(2)
C(14)—C(5)—C(6) 117.5(2) C(20)—C(15)—C(4) 121.7(2)
C(6)—C(5)—C(4) 120.9(2) C(16)—C(15)—C(4) 119.0(2)
C(7)—C(6)—C(5) 122.6(2) C(17)—C(16)—C(15) 119.9(2)
C(11)—C(6)—C(5) 119.4(2) C(18)—C(17)—C(16) 120.7(2)
C(7)—C(6)—C(11) 118.0(2) C(17)—C(18)—C(19) 119.7(2)
C(8)—C(7)—C(6) 121.0(2) C(18)—C(19)—C(20) 120.1(2)
O(2)—C(8)—C(7) 122.9(2) C(15)—C(20)—C(19) 120.3(2)
O(2)—C(8)—C(9) 116.3(2) N(1S)—C(1S)—C(2S)179.0(4)
The melting points were determined on a Kofler stage. The
IR spectra were measured on a Perkin—Elmer 577 instrument in
KBr pellets (1/200). The H NMR spectra were measured on a
1
Bruker ACꢀ300 spectrometer (300 MHz) in DMSOꢀd6; the
chemical shifts are given in the δ scale relative to Me4Si.
2ꢀAminoꢀ4ꢀarylꢀ3ꢀcyano(ethoxycarbonyl)ꢀ4Hꢀ(benꢀ
zo[ f ])chromenes (1—3). Triethylamine (0.5 mL) was added to a
solution of aromatic aldehyde 4 (10 mmol), malononitrile (or
cyanoacetic ester) 5 (10 mmol), and phenol 6 (or naphthol
7—9) (10 mmol) in EtOH (25 mL). The reaction mixture was
refluxed for 10 min. The precipitate that formed was filtered off,
washed with EtOH and hexane, and crystallized from EtOH.
Compound 2a was crystallized from MeCN.
For the synthesis of chromenes 10 and 11, double amounts
of aldehyde and malononitrile were required.
2ꢀAminoꢀ3ꢀcyanoꢀ7ꢀhydroxyꢀ4ꢀ(4ꢀmethoxycarbonylphenyl)ꢀ
4Hꢀchromene (1a). The yield was 78%, m.p. 233 °C (decomp.).
Found (%): C, 66.95; H, 4.34; N, 8.77. C18H14N2O4. Calcuꢀ
lated (%): C, 67.08; H, 4.38; N, 8.69. IR, ν/cm–1: 3480 (O—H);
3408, 3336 (N—H); 2192 (CN); 1702 (C=O); 1656 (NH2 bendꢀ
ing). 1H NMR, δ: 3.83 (s, 3 H, Me); 4.74 (s, 1 H, H(4)); 6.42 (d,
1 H, H(8), J = 1.1 Hz); 6.48 (dd, 1 H, H(6), J = 1.1 Hz, J =
10.0 Hz); 6.78 (d, 1 H, H(5), J = 10.0 Hz); 6.84 (s, 2 H, NH2);
7.31 and 7.89 (both d, 2 H each, C6H4, J = 9.4 Hz); 9.64
(s, 1 H, OH).
2ꢀAminoꢀ3ꢀcyanoꢀ4ꢀ(2,4ꢀdifluorophenyl)ꢀ7ꢀhydroxyꢀ4Hꢀ
chromene (1b). The yield was 87%, m.p. 221 °C. Found (%):
C, 63.90; H, 3.47; N, 9.22. C16H10F2N2O2. Calculated (%):
C, 64.00; H, 3.36; N, 9.33. IR, ν/cm–1: 3480 (O—H); 3408,
3344, 3256 (N—H); 2196 (CN); 1644 (NH2 bending). 1H NMR,
δ: 4.89 (s, 1 H, H(4)); 6.41 (d, 1 H, H(8), J = 0.6 Hz); 6.47 (dd,
1 H, H(6), J = 0.6 Hz, J = 10.5 Hz); 6.57 (br.s, 2 H, NH2); 6.75
(d, 1 H, H(5), J = 10.5 Hz); 6.96 (m, 2 H, C6H3); 7.18 (m, 1 H,
C6H3); 9.39 (s, 1 H, OH).
tween these planes is 88.1°). Apparently, this orientation
of the substituent is determined by forced intramoꢀ
lecular nonbonded contacts (C(3)...C(16), 3.086(3) Å;
C(5)...C(16), 3.057(3) Å; and C(7)...C(20), 3.383(3) Å),
which are shorter than twice the van der Waals radius of
the carbon atom.17
In the planar N(1)—C(2)=C(3)—C(1)≡N(2) fragꢀ
ment, the bond lengths are essentially redistributed as
compared to the standard values18 due to conjugation of
the NH2 and CN groups with the C(2)=C(3) double bond.
In the crystal, molecules 2a and the solvent molꢀ
ecules are linked via the rather strong intermolecular
O(2)—H(1)...N(1S) hydrogen bonds (2 – x, 0.5 + y,
1.5 – z) (O(2)...N(1S), 2.812(4) Å; O(2)—H(1),
0.99(4) Å; H(1)...N(1S), 1.83(4) Å; O(2)—H(1)...N(1S),
171(3)°). The H atoms of the amino group are also
involved in weak intermolecular hydrogen bonds
N(1)—H(1A)...N(2) (–x, 1 – y, 1 – z) (N(1)...N(2),
3.110(4) Å; N(1)—H(1A), 0.90(4) Å; H(1A)...N(2),
2.30(4) Å; N(1)—H(1A)...N(2), 150(3)°) and
N(1)—H(1B)...O(1) (–x, – y, 1 – z) (N(1)...O(1),
3.403(4) Å; N(1)—H(1B), 0.87(4) Å; H(1b)...O(1),
2.58(4) Å; N(1)—H(1B)...O(1), 159(3)°) via which molꢀ
ecules 2a are linked in infinite ribbons.
2ꢀAminoꢀ3ꢀethoxycarbonylꢀ4ꢀ(2,4ꢀdifluorophenyl)ꢀ7ꢀhydrꢀ
oxyꢀ4Hꢀchromene (1c). The yield was 69%, m.p. 205 °C.
Found (%): C, 62.33; H, 4.30; N, 3.91. C18H15F2NO4. Calcuꢀ
lated (%): C, 62.25; H, 4.35; N, 4.03. IR, ν/cm–1: 3424 (O—H);
1
3308 (N—H); 1666 (C=O); 1615 (NH2 bending). H NMR, δ:
1.07 (t, 3 H, Me, J = 8.9 Hz); 3.95 (к, 2 H, OCH2, J = 8.9 Hz);
5.11 (s, 1 H, H(4)); 6.43 (m, 2 H, H(8), H(6)); 6.83 (m, 3 H,
H(5), C6H3); 7.13 (m, 1 H, C6H3); 7.44 (br.s, 2 H, NH2); 9.24
(s, 1 H, OH).
2,7ꢀDiaminoꢀ4ꢀ(3ꢀbromophenyl)ꢀ3ꢀcyanoꢀ4Hꢀchromene
(1d). The yield was 60%, m.p. 232 °C. Found (%): C, 56.19;
H, 3.63; N, 12.19. C16H12BrN3O. Calculated (%): C, 56.16;
H, 3.54; N, 12.28. IR, ν/cm–1: 3456, 3380, 3336 (N—H); 2194
To summarize, the study of the behavior of substituted
phenols and naphthols in threeꢀcomponent condensation
with aldehydes and derivatives of cyanoacetic acid demonꢀ
strated the following facts. First, resorcinol and 3ꢀaminoꢀ
phenol react under the aboveꢀdescribed conditions at poꢀ
sition 6 rather than at position 2 and further cyclization
1
(CN); 1640 (NH2 bending). H NMR, δ: 4.57 (s, 1 H, H(4));
5.21 (br.s, 2 H, C(7)NH2); 6.24 (d, 1 H, H(8), J = 1.4 Hz); 6.29
(dd, 1 H, H(6), J = 1.4 Hz, J = 7.8 Hz); 6.65 (d, 1 H, H(5), J =
7.8 Hz); 6.76 (br.s, 2 H, C(2)NH2); 7.16 (d, 1 H, H(4´), J =
7.1 Hz); 7.26 (t, 1 H, H(5´), J = 7.1 Hz); 7.29 (s, 1 H, H(2´));
7.39 (d, 1 H, H(6´), J = 7.1 Hz).

2242
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 12, December, 2002
Shestopalov et al.
2,7ꢀDiaminoꢀ3ꢀcyanoꢀ4ꢀ(4ꢀmethoxycarbonylphenyl)ꢀ4Hꢀ
chromene (1e). The yield was 89%, m.p. 232 °C. Found (%):
C, 67.37; H, 4.69; N, 13.10. C18H15N3O3. Calculated (%):
C, 67.28; H, 4.71; N, 13.08. IR, ν/cm–1: 3448, 3392,
3340 (N—H); 2182 (CN); 1728 (C=O); 1646 (NH2 bending).
1H NMR, δ: 3.83 (s, 3 H, OMe); 4.63 (s, 1 H, H(4)); 5.23 (br.s,
2 H, C(7)NH2); 6.22 (s, 1 H, H(8), J = 0.6 Hz); 6.27 (dd, 1 H,
H(6), J = 0.6 Hz, J = 10.0 Hz); 6.59 (d, 1 H, H(5), J = 10.0 Hz);
6.79 (br.s, 2 H, C(2)NH2); 7.29 and 7.89 (both d, 2 H each,
C6H4, J = 9.4 Hz).
ing). 1H NMR, δ: 5.49 (s, 2 H, H(4), H(9)); 6.68 and 6.79
(both br.s, 2 H each, 2 NH2); 6.86, 7.33, and 7.96 (all m, 2 H,
6 H, 2 H, 2 H(4´), 2 H(2´), H(5), H(6), H(7), H(8), 2 H(5´)).
2,11ꢀDiaminoꢀ3,10ꢀdicyanoꢀ4,9ꢀdi(4ꢀfluorophenyl)ꢀ4H,9Hꢀ
pyrano[3,2ꢀh]benzo[ f ]chromene (10b). The yield was 72%, m.p.
241 °C (decomp.). Found (%): C, 71.30; H, 3.66; N, 11.20.
C30H18F2N4O2. Calculated (%): C, 71.42; H, 3.60; N, 11.11.
IR, ν/cm–1: 3400—3200 (N—H); 2192 (CN); 1660 (NH2 bendꢀ
ing). 1H NMR, δ: 5.42 (s, 2 H, H(4), H(9)); 6.74 and 6.85
(both br.s, 2 H each, 2 NH2); 7.10, 7.30, and 7.83 (all m, 4 H,
6 H, 2 H, 2 C6H4, H(5), H(6), H(7), H(8)).
2,7ꢀDiaminoꢀ3ꢀcyanoꢀ4ꢀ(2,4ꢀdifluorophenyl)ꢀ4Hꢀchromene
(1f). The yield was 64%, m.p. 208 °C. Found (%): C, 64.08;
H, 3.77; N, 13.97. C16H11F2N3O. Calculated (%): C, 64.21;
H, 3.71; N, 14.04. IR, ν/cm–1: 3456, 3388, 3328 (N—H); 2190
2,8ꢀDiaminoꢀ4,10ꢀdi(4ꢀchlorophenyl)ꢀ3,9ꢀdicyanoꢀ4H,10Hꢀ
chromeno[8,7ꢀh]chromene (11). The yield was 82%, m.p.
320—321 °C (decomp.). Found (%): C, 67.13; H, 3.49; N, 10.27.
C30H18Cl2N4O2. Calculated (%): C, 67.05; H, 3.38; N, 10.43.
IR, ν/cm–1: 3424, 3324, 3196 (N—H); 2200 (CN); 1666
1
(CN); 1632 (NH2 bending). H NMR, δ: 4.82 (s, 1 H, H(4));
4.96 (br.s, 2 H, C(7)NH2); 6.24 (s, 1 H, H(8)); 6.28 and 6.59
(both d, 1 H each, H(6), H(5), J = 8.8 Hz); 6.48 (br.s, 2 H,
C(2)NH2); 6.93 (m, 2 H, C6H3); 7.16 (m, 1 H, C6H3).
2,7ꢀDiaminoꢀ3ꢀcyanoꢀ4ꢀ(3ꢀpyridyl)ꢀ4Hꢀchromene (1g). The
yield was 68%, m.p. 213 °C. Found (%): C, 68.22; H, 4.52;
N, 21.16. C15H12N4O. Calculated (%): C, 68.17; H, 4.58;
N, 21.20. IR, ν/cm–1: 3408, 3312, 3152 (N—H); 2196 (CN);
1656 (NH2 bending). 1H NMR, δ: 4.61 (s, 1 H, H(4)); 5.20
(br.s, 2 H, C(7)NH2); 6.24 (s, 1 H, H(8)); 6.28 and 6.61 (both d,
1 H each, H(5), H(6), J = 8.1 Hz); 6.76 (br.s, 2 H, C(2)NH2);
7.30 (m, 1 H, H(5´)); 7.48 (m, 1 H, H(4´)); 8.40 (m, 2 H,
H(2´), H(6´)).
1
(NH2 bending). H NMR, δ: 4.96 (s, 2 H, H(4), H(10)); 7.09
(br.s, 4 H, 2NH2); 7.25 and 7.38 (both m, 6 H, 4 H, 2 C6H4,
H(6), H(12)); 7.91 (d, 2 H, H(5), H(11), J = 9.4 Hz).
Xꢀray diffraction analysis of compound 2a. Single crystals
of the solvate of 2ꢀaminoꢀ3ꢀcyanoꢀ6ꢀhydroxyꢀ4ꢀphenylꢀ4Hꢀ
benzo[ f ]chromene (2a) (C20H14N2O2•CH3CN) were prepared
by crystallization of 2a from MeCN. The colorless crystals are
monoclinic, at –80 °C, a = 8.643 (4), b = 9.723 (4), c =
21.475 (13) Å, β = 101.55 (4)°, V = 1768 (2) Å3, dcalc
1.335 g cm–3, Z = 4, space group Р21/c.
=
The unit cell parameters and intensities of 4324 reflecꢀ
tions were measured on an automated fourꢀcircle Syntex P21
diffractometer (λ(MoꢀKα), graphite monochromator, θ/2θ scan
technique, θmax = 28°). The structure was solved by direct methꢀ
ods and refined by the fullꢀmatrix leastꢀsquares method with
anisotropic thermal parameters for nonhydrogen atoms. The
acetonitrile molecule was revealed from a difference Fourier
synthesis. The H atoms were located from a difference Fourier
synthesis and refined isotropically. The final reliability factors
were as follows: R1 = 0.056 using 2558 independent reflections,
wR2 = 0.150 using 3997 reflections. All calculations were carried
out with the use of the SHELXLꢀ97 program package.19 The
atomic coordinates and isotropic equivalent (isotropic for
H atoms) thermal parameters were deposited with the Camꢀ
bridge Structural Database.
2ꢀAminoꢀ3ꢀcyanoꢀ6ꢀhydroxyꢀ4ꢀphenylꢀ4Hꢀbenzo[ f ]chroꢀ
mene (2a). The yield was 60%, m.p. 249—251 °C (decomp.).
Found (%): C, 74.42; H, 4.95; N, 11.84. C20H14N2O2•CH3CN.
Calculated (%): C, 74.35; H, 4.82; N, 11.82. IR, ν/cm–1: 3520
(O—H); 3400, 3258, 3210 (N—H); 2196 (CN); 1652 (NH2 bendꢀ
1
ing). H NMR, δ: 5.01 (s, 1 H, H(4)); 6.68 (br.s, 2 H, NH2);
7.12 (m, 8 H, C6H5, H(5), H(9), H(10)); 7.75 (m, 2 H, H(7),
H(8)); 9.63 (br.s, 1 H, OH).
2ꢀAminoꢀ4ꢀ(4ꢀchlorophenyl)ꢀ3ꢀcyanoꢀ6ꢀhydroxyꢀ4Hꢀbenꢀ
zo[ f ]chromene (2b). The yield was 74%, m.p. 263—267 °C
(decomp.). Found (%): C, 68.79; H, 3.73; N, 10.26.
C20H13ClN2O2. Calculated (%): C, 68.87; H, 3.76; N, 10.16.
IR, ν/cm–1: 3490 (O—H); 3380, 3256, 3190 (N—H); 2196 (CN);
1656 (NH2 bending). 1H NMR, δ: 5.00 (s, 1 H, H(4)); 6.70
(br.s, 2 H, NH2); 6.90 (s, 1 H, H(5)); 6.91 and 7.03 (both d,
1 H each, H(9), H(10), J = 10.0 Hz); 7.15 and 7.26 (both d,
2 H each, C6H4, J = 8.9 Hz); 7.66 and 7.72 (both d, 2 H each,
H(7), C(8)H, J = 8.2 Hz); 9.59 (br.s, 1 H, OH).
References
2ꢀAminoꢀ3ꢀcyanoꢀ10ꢀhydroxyꢀ4ꢀ(3ꢀthienyl)ꢀ4Hꢀbenꢀ
zo[ f ]chromene (3). The yield was 69%, m.p. 258—263 °C
(decomp.). Found (%): C, 67.52; H, 3.72; N, 8.85.
C18H12N2O2S. Calculated (%): C, 67.48; H, 3.78; N, 8.74. IR,
ν/cm–1: 3523 (O—H); 3376, 3256 (N—H); 2192 (CN); 1656
1. F. S. Babichev, Yu. A. Sharanin, V. P. Litvinov, V. K.
Promonenkov, and Yu. M. Volovenko, Vnutrimolekulyarnoe
vzaimodeistvie nitril´noi i C—Hꢀ, O—Hꢀ, i S—Hꢀgrupp [Inꢀ
tramolecular Interactions of the Nitrile Group with the C—H,
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1
(NH2 bending). H NMR, δ: 5.38 (s, 1 H, H(4)); 6.78 (d, 1 H,
H(4) of thiophene, J = 5.7 Hz); 6.91 (br.s, 2 H, NH2); 7.31 (m,
5 H, H(5), H(6), H(7), H(8), H(9)); 7.68 and 7.85 (both m,
1 H each, H(2) of thiophene, H(5) of thiophene); 10.22
(br.s, 1 H, OH).
2,11ꢀDiaminoꢀ3,10ꢀdicyanoꢀ4,9ꢀdi(3ꢀthienyl)ꢀ4H,9Hꢀpyraꢀ
no[3,2ꢀh]benzo[ f ]chromene (10a). The yield was 83%,
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C26H16N4O2S2. Calculated (%): C, 64.98; H, 3.36; N, 11.66.
IR, ν/cm–1: 3400—3200 (N—H); 2186 (CN); 1646 (NH2 bendꢀ
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Received February 5, 2002;
in revised form July 2, 2002