Further studies on the reaction of ethyl benzoylacetate with malononitrile: Synthesis of some novel pyridine and pyridazine derivatives

Article abstract of DOI:10.1016/S0040-4020(01)00613-5

2-Cyano-5-phenyl-3,5-dioxopentanonitrile undergoes alcoholysis followed by Knoevenagel condensation to afford ethyl 4,4-dicyano-3-phenyl-3-butenoate, a thermo dynamically controlled product, which undergoes cyclization in acid medium to afford 2,6-dihydroxy-4-phenylnicotinonitrile. Some azo derivatives of nicotinonitriles and of 2-aminopyran are described. 5-Arylazo-2-aminopyrans are transformed by acid treatment into pyridazine derivatives, whereas without the arylazo substituent pyridines are obtained.

Full text of DOI:10.1016/S0040-4020(01)00613-5

TETRAHEDRON
Pergamon
Tetrahedron 57 32001) 6787±6791
Further studies on the reaction of ethyl benzoylacetate with
malononitrile: synthesis of some novel pyridine and pyridazine
derivativesq
Fathy M. Abdelrazek,p Abdellatif M. Salah El-Din and Ahmed E. Mekky
Chemistry Department, Faculty of Science, Cairo University, Giza, A.R. Egypt
Received 28 February 2001; revised 8 May 2001; accepted 31 May 2001
AbstractÐ2-Cyano-5-phenyl-3,5-dioxopentanonitrile undergoes alcoholysis followed by Knoevenagel condensation to afford ethyl 4,4-
dicyano-3-phenyl-3-butenoate, a thermo dynamically controlled product, which undergoes cyclization in acid medium to afford 2,6-di-
hydroxy-4-phenylnicotinonitrile. Some azo derivatives of nicotinonitriles and of 2-aminopyran are described. 5-Arylazo-2-aminopyrans are
transformed by acid treatment into pyridazine derivatives, whereas without the arylazo substituent pyridines are obtained. q 2001Elsevier
Science Ltd. All rights reserved.
In the last decade we have been involved in an agrochemical
programme aiming to develop new simple routes to func-
tionally substituted heterocycles with anticipated biological
activity.1±3 We have recently reported that ethyl benzoyl-
acetate reacts with malononitrile to afford the pentanonitrile
derivative 1 3Scheme 1) as a Claisen condensation product.4
Now we report the results of further investigations on this
reaction and the synthesis of some new pyridazine derivatives.
diazonium salts 6a±d to afford the coloured hydrazo
derivatives 7a±d, respectively. Elemental analysis and
spectral data are in agreement with the proposed structures.
Compounds 7a±d could be cyclized on fusion with ammo-
nium acetate in an oil bath at 2008C to afford the pyridazine
derivatives 8a±d, which were identical with the same
compounds obtained previously by another route.4
It now became clear that the reaction of ethyl benzoyl-
acetate with malononitrile proceeds via initial Claisen
condensation to afford product 1 as a kinetically controlled
product which, on long standing in ethanol, undergoes
alcoholysis to give back the reacting constituents which
then undergo a Knoevenagel condensation to afford 4 as
the thermodynamically controlled product, presumably via
the intermediate steps 2 and 3 according to the sequence
shown in Scheme 1.
When the pentanonitrile
1 3prepared as previously
reported4) was left in an ethanolic solution at room tempera-
ture for about 15 days, a solid crystalline product appeared
in the ¯ask. After separation and puri®cation, this solid had
a melting point 1908C. Mass spectral measurements showed
a molecular ion peak at m/z 240. The IR spectrum showed
absorption bands at 2207 and 1712 cm21 corresponding to
1
cyano and ester carbonyl functions, respectively. The H
NMR spectrum revealed a triplet 33H) at d 1.2 3Jˆ7 Hz),
a quartet 32H) at d 3.8 3Jˆ7 Hz) and a singlet 32H) at d 4.3
besides an aromatic multiplet 35H) at d 7.3±7.85. On the
basis of these data the Knoevenagel condensation structure
4 was assigned to this product 3Scheme 1).
It should be mentioned that the reaction of ethyl benzoyl-
acetate with malononitrile has been previously reported
to afford an oily product which was thought to be the
Knoevenagel condensation 4.8,9 This oily product afforded
the pyridine derivative 10a 3mp 288±2908C)8 on heating
with 70% sulfuric acid on a boiling water bath.
The structure of compound 4 was consistent with its reac-
tion with elemental sulfur to afford the thiophene derivative
5.5±7 The structure of the thiophene 5 was assigned on the
basis of analytical and spectral data.
In our hands, boiling of the oily product 1 3in an ethanolic
solution) directly after the reaction time with conc. HCl led
to precipitation of a pale yellow crystalline solid product
1
Compound 4 also undergoes the coupling reaction with the
3mp 2938C) in 70% yield. The IR and H NMR spectra of
this product revealed that it is the same pyridine derivative
described above.8 Structure 10a or its tautomeric 10b or 10c
was assigned to this product.10
q This work is abstracted in part from the MSc thesis of A. E. Mekky.
Keywords: nicotinonitriles; azo derivatives; pyridazines.
Corresponding author; e-mail: frazek@chem-sci.cairo.eun.eg
p
As compound 10 could not be obtained from 1 but through
0040±4020/01/$ - see front matter q 2001Elsevier Science Ltd. All rights reserved.
PII: S0040-4020301)00613-5

6788
F. M. Abdelrazek et al. / Tetrahedron 57 *2001) 6787±6791
Scheme 1.
4, it is assumed that the presence of conc. HCl or H2SO4 has
enhanced the process of alcoholysis of 1 by protonation of
the carbonyl group creating a positive charge on the car-
bonyl carbon atom, thus facilitating attack by ethanol to
afford 4. Compound 4 3as intermediate in this process)
then undergoes hydration of one of the cyano functions to
afford the amide intermediate 9 which eliminates ethanol to
afford the nicotinonitrile derivative 10.
In support of this assumption, compound 4 could be
transformed into 10 upon re¯ux in ethanolic conc. HCl
presumably via the intermediacy of 9.
Scheme 2.

F. M. Abdelrazek et al. / Tetrahedron 57 *2001) 6787±6791
6789
The 5-azo derivatives of 2,6-disubstituted-4-methylnico-
tinonitriles have found wide applications in the dyeing of
polyester, acrylic, cellulosic and polyamide ®bers and
PVC.10 This prompted us to prepare the azo derivatives of
the pyridine-3-carbonitrile derivatives described in this
work that may ®nd a similar application.
Jˆ7 Hz, 2H, CH2), 4.3 3s, 2H, CH2), 7.25±7.80 3m, 5H,
arom); m/z 240 3M1, 27.5%), 195 317.5%), 168 3100%),
77 321.5%).
1.1.2. Ethyl 2-amino-3-cyano-4-phenylthiophene-5-car-
boxylate 5. To a solution of 4 32.4 g, 10 mmol) in 25 mL
ethanol and elemental sulfur 310 mmol), a catalytic amount
of triethylamine was added and re¯uxed for 3 h, then ®ltered
hot and left to cool to room temperature. The solid product
formed was ®ltered off and recrystallized from ethanol/
DMF to afford 5 as dark brown powder. 31.6 g, 60%); mp
3108C [Found: C, 61.80; H, 4.50; N, 10.20; S, 11.70.
C14H12N2O2S requires C, 61.74; H, 4.44; N, 10.28; S,
11.77]; nmax 3400±3200 3NH2) 2222 3CN), 1710 3CvO);
dH 3200 MHz, DMSO-d6) 1.2 3t, Jˆ7 Hz, 3H, CH3), 3.9 3q,
Jˆ7 Hz, 2H, CH2), 7.29±7.55 3m, 5H, arom), 7.57 3bs, 2H,
NH2).
Thus, compound 10 couples with the diazonium salts 6a±d
in the free 5-position to afford the azo/hydrazo derivatives
11a±d, respectively, as inferred from the analytical and
spectral data.
On the other hand the pentanonitrile 1 was cyclized into the
4-oxopyran 12 which was in turn transformed into the
4-oxodihydropyidine 13 upon re¯ux in AcOH/H2SO4.4
Azo coupling of 13 with 6a±d gave new azo derivatives
for which structures 14a±d were assigned, respectively,
on the basis of their analytical and spectral data, Scheme 2.
1.1.3. 2,6-Dihydroxy-4-phenyl-3-pyridinecarbonitrile 10.
Method A: To the oily product 14 321.2 g, 100 mmol)
directly after the reaction time is up was added 2 mL of
concentrated hydrochloric acid and then boiled with
scratching for 30 min, the precipitated solid was ®ltered
off and recrystallized from ethanol/DMF to afford 10 as
yellowish brown crystals. 314.8 g, 70%); mp 2938C
3EtOH/DMF), [Found: C, 67.70; H, 3.90; N, 13.10.
C12H8N2O2 requires C, 67.92; H, 3.80; N, 13.20]; nmax
3440 3br, OH), 22213CN); dH 3200 MHz, DMSO-d6) 5.70
3s, 1H, pyridine H-5), 7.45 3s, 1H, OH), 7.48±7.52 3m, 5H,
arom), 7.55 3s, 1H, OH; m/z 212 3M1, 100%).
In order to prove the structure of compounds 14a±d chemi-
cally, it was thought to obtain them from the corresponding
5-arylazo derivatives of 4-oxopyran: 15a±d by re¯ux in
AcOH/H2SO4. Thus compounds 15a±d were prepared by
azo coupling of 12 with 6a±d and coloured azo compounds
have been obtained and their structures were established on
the basis of their analytical and spectral data. Re¯uxing
these azo derivatives 15a±d in acetic/sulfuric acid mixture
did not, however, afford the azo derivatives 14a±d but
afforded other new compounds. Analytical and spectral
data of these new compounds suggested the pyridazine
structures 17a±d 3Scheme 2).
Method B: To a solution of 4 32.4 g, 10 mmol) in 25 mL
ethanol was added 2 mL of concentrated hydrochloric acid
and the reaction mixture was re¯uxed for 3 h, then left to
cool to room temperature. The solid product formed was
®ltered off and recrystallized from ethanol/DMF to afford
1.6 g 375%) of a product, which is identical to that obtained
from method A.
The formation of the pyridazines 17 apparently proceeded
via hydrolysis of the azo pyrans 15 to afford the acyclic
intermediates 16 which then undergo cyclization via the
attack of the hydrazone NH on the enamine carbon atom
with loss of ammonia. Similar transformations of azopyrans
into pyridazines are known in the literature.11
1.2. Ethyl 2-arylazo-4,4-dicyano-3-phenyl-3-butenoates
7a±d, 5-Arylazo-2,6-dihydroxy-4-phenyl-3-pyridine-
carbonitriles 11a±d, 5-arylazo-2,4-dihydroxy-6-phenyl-
3-pyridine-carbonitriles 14a±d and 5-arylazo-2-amino-
6-phenyl-4-oxo-4H-pyran-3-carbonitriles 15a±d
,general procedure)
1. Experimental
1.1. General
Melting points were determined on an electrothermal 39100)
apparatus and are uncorrected. The IR spectra were
recorded as KBr pellets on a Perkin±Elmer 1430 spectro-
To a cold solution of 4, 10, 13 or 12 310 mmol) and sodium
acetate 1.5 g in 35 mL of ethanol was added dropwise a cold
solution of diazotized amines 6a±d 3aniline, p-anisidine,
p-chloroaniline, p-toluidine, 10 mmol) while stirring. The
addition took about 30 min, after which stirring was con-
tinued for further 1h. The coloured solid precipitates were
collected by ®ltration, washed with cold water, and
recrystallized from ethanol to afford the title compounds,
respectively.
1
photometer. The H-NMR spectra were taken on a Varian
Gemini 200 MHz spectrometer in DMSO-d6 using TMS as
internal standard. Mass spectra were taken on a Shimadzu
GCMS-GB 1000 PX 370 eV). Elemental analyses
were carried out by the Microanalytical Center at Cairo
University.
1.1.1. Ethyl 4,4-dicyano-3-phenyl-3-butenoate 4. The oily
product 1 321.2 g, 100 mmol; prepared as previously
described4) was left in ethanol for 15 days at room
temperature. The solid crystalline precipitate was collected
by ®ltration and recrystallized from ethanol to give 4 as
colourless needle crystals. 312.0 g, 50%); mp 1908C
[Found: C, 70.10; H, 5.10; N, 11.60. C14H12N2O2 requires
C, 69.99; H, 5.03; N, 11.66]; nmax 2207 3CN), 1712 3CvO);
dH 3200 MHz, DMSO-d6) 1.25 3t, Jˆ7 Hz, 3H, CH3), 3.8 3q,
1.2.1. Compound 7a. Brown crystals 32.93 g, 85%), mp
2638C 3EtOH); [Found: C, 69.80; H, 4.80; N, 16.40.
C20H16N4O2 requires C, 69.76; H, 4.68; N, 16.27]; nmax
3KBr) 3320 3NH), 2210 3CN), 1690 3CvO); dH
3200 MHz, DMSO-d6) 1.15 3t, Jˆ7 Hz, 3H, CH3), 4.13q,
Jˆ7 Hz, 2H, CH2), 7.20±7.45 3m, 10H, arom), 7.55 3s, 1H,
NH).

6790
F. M. Abdelrazek et al. / Tetrahedron 57 *2001) 6787±6791
1.2.2. Compound 7b. Red powder 32.99 g, 80%), mp 2788C
3EtOH); [Found: C, 67.20; H, 4.90; N, 15.10. C21H18N4O3
requires C, 67.37; H, 4.85; N, 14.96]; nmax 3KBr) 3320
3NH), 2215 3CN), 1690 3CvO); dH 3200 MHz, DMSO-d6)
1.15 3t, Jˆ7 Hz, 3H, CH3), 3.85 3s, 3H, CH3), 4.13q,
Jˆ7 Hz, 2H, CH2), 7.02 3d, 2H, arom), 7.25 3d, 2H,
arom), 7.40±7.45 3m, 5H, arom), 7.55 3s, 1H, NH); m/z
373 3M1, 85%), 345 310.5%), 301 316.7%), 77 322.7%).
1.2.10. Compound 14b. Redish brown powder 32.35 g,
68%), mp 2138C 3EtOH); [Found: C, 66.0; H, 4.10; N,
16.20. C19H14N4O3 requires C, 65.89; H, 4.07; N, 16.18];
nmax 3KBr) 3350±3300 3b, OH), 2210 3CN), 1570 3NvN);
dH 3200 MHz, DMSO-d6) 3.78 3s, 3H, CH3), 6.88 3d, 2H,
Jˆ8 Hz, arom), 7.10 3d, 2H, Jˆ8 Hz arom), 7.20±7.30 3m,
5H, arom), 8.30 3s, 2H, 2OH).
1.2.11. Compound 14c. Brown powder 32.52 g, 72%), mp
2938C 3EtOH/DMF); [Found: C, 61.70; H, 3.20; N, 16.10;
Cl, 10.20. C18H11ClN4O2 requires C, 61.64; H, 3.16; N,
15.97; Cl, 10.11]; nmax 3KBr) 3400±3350 3OH),
22143CN), 1575 3NvN); dH 3200 MHz, DMSO-d6) 6.98
3d, 2H, Jˆ8 Hz, arom), 7.23 3d, 2H, Jˆ8 Hz, arom),
7.30±7.38 3m, 5H, arom), 8.35 3s, 2H, OH).
1.2.3. Compound 7c. Brown powder 32.94 g, 78%), mp
1628C 3EtOH); [Found: C, 63.50; H, 3.90; N, 14.90; Cl,
9.40. C20H16N4O2Cl requires C, 63.41; H, 3.99; N, 14.79,
Cl, 9.36]; nmax 3KBr) 3320 3NH), 2210 3CN), 1695 3CvO);
dH 3200 MHz, DMSO-d6) 1.2 3t, Jˆ7 Hz, 3H, CH3), 4.0 3q,
Jˆ7 Hz, 2H, CH2), 7.12 3d, 2H, arom), 7.25 3d, 2H, arom),
7.35±7.45 3m, 5H, arom), 7.62 3s, 1H, NH).
1.2.12. Compound 14d. Dark brown powder 32.34 g, 71%),
mp.3308C 3EtOH/DMF); [Found: C, 69.20; H, 4.30; N,
17.00. C19H14N4O2 requires C, 69.08; H, 4.27; N, 19.96];
nmax 3KBr) 3340±3300 3b, OH), 2210 3CN), 1585 3NvN);
dH 3200 MHz, DMSO-d6) 2.35 3s, 3H, CH3), 6.93 3d, 2H,
arom), 7.12 3d, 2H, arom), 7.25±7.35 3m, 5H, arom), 8.39 3s,
2H, OH).
1.2.4. Compound 7d. Light brown powder 32.68 g, 75%),
mp 1708C 3EtOH); [Found: C, 70.50; H, 5.10; N, 15.70.
C21H18N4O2 requires C, 70.38; H, 5.06; N, 15.63]; nmax
3KBr) 3330 3NH), 2220 3CN), 1685 3CvO); dH
3200 MHz, DMSO-d6) 1.14 3t, Jˆ7 Hz, 3H, CH3), 2.37 3s,
3H, CH3), 3.9 3q, Jˆ7 Hz, 2H, CH2), 7.08 3d, 2H, arom),
7.22 3d, 2H, arom), 7.28±7.48 3m, 5H, arom), 7.60 3s, 1H,
NH).
1.2.13. Compound 15a. Yellowish green crystals 32.21g,
70%), mp 3108C 3EtOH/DMF); [Found: C, 68.40; H, 3.70;
N, 17.70. C18H12N4O2 requires C, 68.35; H, 3.82; N, 17.71];
nmax 3KBr) 3400±3230 3b, OH, NH2), 2204, 3CN), 1560
3NvN); dH 3200 MHz, DMSO-d6) 7.25±7.55 3m, 10H,
arom), 7.65 3bs, 2H, NH2).
1.2.5. Compound 11a. Dark yellow crystals 32.20 g, 70%),
mp 2528C 3EtOH); [Found: C, 68.30; H, 3.70; N, 17.80.
C18H12N4O2 requires C, 68.35; H, 3.82; N, 17.71]; nmax
3KBr) 3417±3330 3b, OH), 2214 3CN); dH 3200 MHz,
DMSO-d6) 5.56 3s, 1H), 7.20±7.52 3m, 10H, arom), 7.65
3s, 1H).
1.2.14. Compound 15b. Crimson red powder 32.69 g, 78%),
mp 2488C 3EtOH); [Found: C, 65.80; H, 4.10; N, 16.10.
C19H14N4O3 requires C, 65.89; H, 4.07; N, 16.18]; nmax
3KBr) 3410±3290 3b, OH, NH2), 2210 3CN), 1580
3NvN); dH 3200 MHz, DMSO-d6) 3.75 3s, 3H, CH3), 6.96
3d, 2H, Jˆ7.7 Hz, arom), 7.26 3d, 2H, Jˆ7.7Hz, arom),
7.45±7.55 3m, 5H, arom), 7.62 3s, 2H, NH2).
1.2.6. Compound 11b. Dark red crystals 32.56 g, 74%), mp
2788C 3EtOH); [Found: C, 65.80; H, 4.10; N, 16.10.
C19H14N4O3 requires C, 65.89; H, 4.07; N, 16.18]; nmax
3KBr) 3450±3380 3OH), 2210 3CN), 1690 3CvO); dH
3200 MHz, DMSO-d6) 3.84 3s, 3H, CH3), 5.52 3s, 1H),
6.98 3d, 2H, Jˆ8 Hz, arom), 7.25 3d, 2H, Jˆ8 Hz arom),
7.52±7.55 3m, 5H, arom), 7.66 3s, 1H).
1.2.15. Compound 15c. Dark yellow crystals 32.66 g, 76%),
mp 2628C 3EtOH/DMF); [Found: C, 61.60; H, 3.10; N,
16.10; Cl, 10.10. C18H11ClN4O2 requires C, 61.64; H,
3.16; N, 15.97; Cl, 10.11]; nmax 3KBr) 3400±3350 3OH,
NH2), 2205 3CN), 1595 3NvN); dH 3200 MHz, DMSO-
d6) 6.94 3d, 2H, Jˆ8 Hz, arom), 7.15 3d, 2H, Jˆ8 Hz,
arom), 7.30±7.36 3m, 5H, arom), 8.28 3bs, 2H, NH2).
1.2.7. Compound 11c. Yellow crystals 32.52 g, 72%),
mp.3308C 3EtOH/DMF); [Found: C, 61.60; H, 3.20; N,
16.10; Cl, 10.10. C18H11 Cl N4O2 requires C, 61.64; H,
3.16; N, 15.97; Cl, 10.11]; nmax 3KBr) 3400±3350 3OH),
2212 3CN), 1695 3CvO); dH 3200 MHz, DMSO-d6) 5.65
3s, 1H), 6.95 3d, 2H, Jˆ8 Hz, arom), 7.22 3d, 2H, Jˆ8 Hz,
arom), 7.40±7.50 3m, 5H, arom), 7.64 3s, 1H).
1.2.16. Compound 15d. Lemon green crystals 32.34 g,
71%), mp 3008C 3EtOH/DMF); [Found: C, 69.10; H, 4.40;
N, 16.90. C19H14N4O2 requires C, 69.08; H, 4.27; N, 16.96];
nmax 3KBr) 3330±3200 3b, OH, NH2), 2214 3CN), 1566
3NvN); dH 3200 MHz, DMSO-d6) 2.34 3s, 3H, CH3), 6.90
3d, 2H, arom), 7.10 3d, 2H, arom), 7.25±7.38 3m, 5H, arom),
8.32 3s, 2H, NH2).
1.2.8. Compound 11d. Orange crystals 32.47 g, 75%), mp
2638C 3EtOH); [Found: C, 69.0; H, 4.20; N, 17.10.
C19H14N4O2 requires C, 69.08; H, 4.27; N, 19.96]; nmax
3KBr) 3440±3370 3b, OH), 2215 3CN); dH 3200 MHz,
DMSO-d6) 2.35 3s, 3H, CH3), 5.45 3s, 1H), 6.93 3d, 2H,
arom), 7.16 3d, 2H, arom), 7.30±7.45 3m, 5H, arom), 7.60
3s, 1H).
1.3. Ethyl 1-aryl-5-cyano-6-imino-4-phenyl-1,6-dihydro-
pyridazine-3-carboxylates 8a±d
1.2.9. Compound 14a. Dark brown powder 32.1g, 66%),
mp.3308C 3EtOH/DMF); [Found: C, 68.30; H, 3.90; N,
17.80. C18H12N4O2 requires C, 68.35; H, 3.82; N, 17.71];
A mixture of 310 mmol) of each of the azo derivatives 7a±d
and 1g of ammonium acetate 315 mmol) was fused on an oil
bath at 2008C for 2 h. The melt was left to cool to room
temperature and triturated with ethanol. The solid precipi-
tates were ®ltered off and recystallized from acetic acid to
n
max 3KBr) 3417±3330 3b, OH), 2210, 3CN), 1550 3NvN);
dH 3200 MHz, DMSO-d6) 7.20±7.42 3m, 10H, arom), 8.4
3bs, 2H, 2OH).

F. M. Abdelrazek et al. / Tetrahedron 57 *2001) 6787±6791
6791
afford the title compounds, which were identical to those
previously reported.4 The identity of the compounds was
inferred from comparison of mp, mixed mp, TLC and spec-
tral data.
1.4.4. Compound 17d. Brown powder 32.0 g, 62%), mp
3208C 3EtOH/DMF); [Found: C, 69.00; H, 4.10; N, 12.70.
C19H13N3O3 requires C, 68.88; H, 3.95; N, 12.68]; nmax
3KBr) 3350 3br, OH), 2210 3CN), 1700 and 1655 32
CvO); dH 3200 MHz, DMSO-d6) 2.36 3s, 3H, CH3), 6.94
3d, 2H, arom), 7.10 3d, 2H, arom), 7.20±7.34 3m, 5H, arom),
11.69 3s, 1H, OH).
1.4. 1-Aryl-3-benzoyl-6-hydroxy-4-oxo-1,4-dihydro-
pyridazine-5-carbonitriles 17a±d
To a solution of each of the azopyrans 15a±d 310 mmol) in
30 mL of glacial acetic acid was added 1mL of concen-
trated sulfuric acid and the mixture was re¯uxed for 1h,
then left to cool to room temperature. The precipitated
solid was ®ltered off and recrystallized to afford 17a±d.
References
1. Abdelrazek, F. M. J. Prakt. Chem. 1990, 332 34), 479±483.
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3. Abdelrazek, F. M.; Bahbouh, M. S. Phosphorus, Sulfur,
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1.4.1. Compound 17a. Brown crystals 32.0 g, 65%), mp
3008C 3EtOH/DMF); [Found: C, 68.30; H, 3.60; N, 13.30.
C18H11N3O3 requires C, 68.14; H, 3.49; N, 13.24]; nmax
3KBr) 3380 3br, OH), 2215 3CN), 1720 and 1655 32
CvO); dH 3200 MHz, DMSO-d6), 7.05±7.30 3m, 10H,
arom), 11.8 3s, 1H, OH).
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1.4.2. Compound 17b. Crimson red powder 32.39 g, 69%),
mp 2808C 3EtOH/DMF); [Found: C, 65.60; H, 3.90; N,
12.20. C19H13N3O3 requires C, 65.70; H, 3.77; N, 12.10];
nmax 3KBr) 3350 3br, OH), 2210 3CN), 1715 and 1665 32
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3d, 2H, Jˆ8 Hz, arom), 7.18 3d, 2H, Jˆ8 Hz, arom), 7.25±
7.35 3m, 5H, arom), 11.75 3s, 1H, OH).
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T. P.; Steel, P. J. J. Heterocycl. Chem. 1995, 32, 979±984.
11. Behbehani, H.; Abdel-Khalik, M. M.; Elnagdi, M. H. Org.
Prep. Proced. Int. 1999, 31 35), 551±557.
1.4.3. Compound 17c. Brick red powder 32.0 g, 58%), mp
2888C 3EtOH/DMF); [Found: C, 61.40; H, 3.00; N, 12.10;
Cl, 10.00. C18H10 Cl N3O3 requires C, 61.46; H, 2.87; N,
11.95; Cl, 10.08]; nmax 3KBr) 3330 3br, OH), 2204 3CN),
1710 and 1668 32 CvO); dH 3200 MHz, DMSO-d6) 6.84 3d,
2H, Jˆ8 Hz, arom), 7.10 3d, 2H, Jˆ8 Hz, arom), 7.24±7.32
3m, 5H, arom), 11.65 3s, 1H, OH).