Application of secondary amines in the synthesis of some new spiro heterocyclic compounds

Article abstract of DOI:10.1080/10426500802713283

1-Anilinocycloalkanecarbonitriles 1a-c were prepared and reacted with active methylene reagents to give compounds 5a-c through 10a-c and reacted with different other reagents such as benzaldehyde, ethyl aminoacetate, ethyl mercaptoacetate, or hydrazine ca

Full text of DOI:10.1080/10426500802713283

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Phosphorus, Sulfur, and Silicon and the
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Application of Secondary Amines
in the Synthesis of Some New Spiro
Heterocyclic Compounds
A. M. Soliman a , A. A. Sultan a , Omran Abd Ellah a & A. K. El-Shafei
a
a Chemistry Department, Faculty of Science, Sohag University, Egypt
Published online: 02 Jul 2010.
To cite this article: A. M. Soliman , A. A. Sultan , Omran Abd Ellah & A. K. El-Shafei (2010):
Application of Secondary Amines in the Synthesis of Some New Spiro Heterocyclic Compounds,
Phosphorus, Sulfur, and Silicon and the Related Elements, 185:7, 1301-1314
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Phosphorus, Sulfur, and Silicon, 185:1301–1314, 2010
Copyright ꢀC Taylor & Francis Group, LLC
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426500802713283
APPLICATION OF SECONDARY AMINES IN THE
SYNTHESIS OF SOME NEW SPIRO HETEROCYCLIC
COMPOUNDS
A. M. Soliman, A. A. Sultan, Omran Abd Ellah,
and A. K. El-Shafei
Chemistry Department, Faculty of Science, Sohag University, Egypt
1-Anilinocycloalkanecarbonitriles 1a–c were prepared and reacted with active methylene
reagents to give compounds 5a–c through 10a–c and reacted with different other reagents
such as benzaldehyde, ethyl aminoacetate, ethyl mercaptoacetate, or hydrazine carboth-
ioamide, which afforded the desired spiro heterocycles compounds 11a–c through 14a–c.
Keywords Anilinocycloalkane; halocompounds; malononitrile; spirocycloalkanyl
INTRODUCTION
The synthesis of new spiro heterocyclic systems was one of the targets of research
work done in our laboratory. Recently, and in accordance with the considerable impor-
tance of ketoketen,1 or cyanoketen S,S-acetals,2 as well as heterocyclic keten N,N ,3–8
N,S ,9–11 or N,O ,12 acetals we have reported the synthesis of some new spiro hetero-
cyclic systems.13–15 Photochromic organic molecules (including spiro pyrans and spiroox-
azines) have been under intense study in the last few years because they can be used in
optical systems for recording and displaying information, as well as in sensors, optobio-
and optoelectronics, transport systems, and catalysis.16–19
RESULTS AND DISCUSSION
In order to find out new and efficient routes for the synthesis of a new class
of spiro heterocycles we used 1-anilinocycloalkanecarbonitriles 1a–c, which proved to
be excellent precursors. This class of compounds was prepared either by reaction of
N-cycloalkylidinoanilines, prepared20–21 by treatment of aniline with the corresponding
cyclic ketone, along with hydrocyanic acid, or directly22 by treatment with a cold solution
of the cyclic ketone in glacial acetic acid successively with aniline and sodium cyanide.
We report herein also the reaction of cyclopentanone, cyclohexanone, or cy-
cloheptanone with 1,2-diaminobenzene, 2-aminophenol, or 2-(methylthio)aniline
following the same procedure, where we were able to obtain the corresponding 1-
substituted phenylaminocycloalkanecarbonitriles, namely, 1-[(2-aminophenyl)amino]
Received 11 July 2008; accepted 22 December 2008.
Address correspondence to A. M. Soliman, Chemistry Department, Faculty of Science, Sohag University,
Egypt. E-mail: a sol2000@yahoo.com
1301

1302
A. M. SOLIMAN ET AL.
cycloalkanecarbonitrile 2a–c, 1-[(2-hydroxyphenyl)amino]cycloalkanecarbonitriles 3a–c,
or 1-[(2-methylthiopheyl)amino]cycloalkane carbonitriles 4, respectively. These com-
pounds were also used as important substrates for the synthesis of some new spiro
heterocycles.
The synthesis of compounds 1–4 was assumed to go through a nucleophlic addition
of the –NH2 group in the starting materials at the carbonyl group of the cyclic ketones,
followed by another nucleophilic attack of the cyanide ion CN at the C OH linkage with
elimination of the OH ion (see Scheme 1, Tables I and II).
Scheme 1
Compounds 1a–c were allowed to react with malononitrile in DMF containing TEA
as a catalyst, where the corresponding spiro[cycloalkanyl-1,2-(3-amino-4-cyano-5-amino-
1-phenyl)pyrroles] 5a–c were obtained. The reaction pathway was assumed to follow a
nucleophilic addition of the NH group at the CN function of malononitrile, followed by
another nucleophilic addition of the active methylene group of CH2CN at the cyano
function of the substrate and cyclization.
In analogy with malononitrile, the reaction of compounds 1a–c with a variety of active
methylene reagents including ethylcyanoacetate, cyanoacetohydrazide (ethylacetoacetate),
or diethylmalonate was achieved following the stated experimental conditions to give
desired spiro heterocycles. The reaction of 1a–c with ethylcyanoacetate was assumed to
go through a nucleophilic attack of the NH group at the carbonyl ester with subsequent
elimination of the ethanol molecule followed by another nucleophilic attack of the CH2
group of the reagent at the cyano function and cyclization to give compounds 6a–c.
The reaction of compounds 1a–c with cyanoacetohydrazide underwent a nucleophilic
attack of the –NH group in the substrate at the cyano function of the reagent, followed
by another nucleophilic attack of the CH2 group in the reagent at the cyano group
and cyclization, elimination of NH3 molecule and cyclization afforded the desired spiro
heterocycles 7a–c. In addition, the reaction of compounds 1a–c with ethyl acetoacetate was
carried out in the same previous experimental conditions that gave compounds 9a–c. (8a–c)
and by using diphenylether as a solvent, it gave compounds 9a–c. Dimethyl malonate ester
was allowed to react with 1a–c in the same reaction conditions mentioned before and gave
the compounds 10a–c (see Scheme 2, Tables I and II).

SYNTHESIS OF SPIRO HETEROCYCLIC COMPOUNDS
1303
HN
CN
NH2
N
Ph
CH2(CN)2
DMF/TEA
(n)
5a-c
O
CN
NCCH2COOC2H5
DMF/TEA
N
Ph
NH2
(n)
6a-c
O
HN
NH
NH
Ph
CN
NCCH2CONHNH2
DMF/TEA
N
N
H
Ph
(n)
7a-c
1a-c
a
b
c
n = 1
n = 2
n = 3
O
N
COCH3
NH2
Ph
DMF/TEA
CH COCH COOEt
3
2
(n)
8a-c
CH3
O
O
phOph/TEA
N
Ph
NH
(n)
9a-c
O
N
COOCH3
NH2
CH2(COOCH3)2
p-xylene/TEA
Ph
(n)
10a-c
Scheme 2
Compounds 1a–c were allowed to react with other reagents, such as benzaldehyde,
ethyl aminoacetate, ethyl mercaptoacetate, or hydrazine carbothioamide, which afforded
the desired spiro heterocycles 11a–c, 12a–c, 13a–c, or 14a–c, respectively.

1304
A. M. SOLIMAN ET AL.
Table I Analytical and experimental data of the new compounds
Analysis (calc./found)
Product
No.
Time of
Reaction
Yield
%
Molecular
Formula
Mp◦C
59
C%
H%
N%
1a
1b
1c
2a
2b
2c
3a
3b
3c
4
1 h
1 h
1 h
1 h
1 h
1 h
1 h
1 h
1 h
1 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
90
90
90
80
85
80
90
90
90
60
65
75
60
60
65
70
60
70
62
60
50
55
90
85
87
40
C12H14N2
186.25
77.38
77.47
77.96
77.82
78.46
78.36
71.62
71.50
72.52
72.40
73.33
73.21
71.27
71.40
72.20
72.32
73.01
73.13
68.25
68.36
71.41
71.52
72.16
72.34
72.83
72.70
71.13
71.00
71.89
71.73
72.57
72.40
67.15
67.30
68.07
68.26
68.89
68.77
71.09
71.22
71.81
71.68
72.46
72.60
71.09
71.32
71.81
71.69
72.46
72.57
67.12
67.00
7.58
7.44
8.05
8.16
8.47
8.58
7.51
7.62
7.96
7.82
8.35
8.49
6.97
6.85
7.45
7.33
7.87
7.70
7.36
7.47
6.39
6.25
6.81
6.70
7.19
6.90
5.96
6.11
6.41
6.55
6.80
6.95
6.00
6.11
6.42
6.35
6.80
6.90
6.70
6.55
7.08
7.28
7.43
7.55
6.70
6.56
7.08
7.19
7.43
7.32
6.33
6.46
15.04
15.19
13.99
14.10
13.07
13.12
20.88
20.74
19.52
19.39
18.32
18.19
13.85
13.96
12.95
12.81
12.16
12.32
11.37
11.25
22.21
22.38
21.04
21.24
19.98
19.84
16.58
16.43
15.72
15.61
14.93
14.80
20.88
20.65
19.84
19.70
18.90
18.72
10.36
10.21
9.85
76
C
C
C
C
C
13H16N2
200.28
14H18N2
214.31
12H15N3
201.26
13H17N3
215.29
85
147
150
115
65
14H19N3
229.32
C
C
C
12H14N2O
202.25
13H16N2O
216.28
14H18N2O
230.30
70
81
67
C
14H18N2S
246.37
5a
5b
5c
6a
6b
6c
7a
7b
7c
8a
8b
8c
9a
9b
9c
10a
140
160
150
180
200
210
140
170
193
100
95
C
15H16N4
252.31
C
16H18N4
266.33
C
17H20N4
280.37
C
C
C
C
C
C
15H15N3O
253.30
16H17N3O
267.32
17H19N3O
281.35
15H16N4O
268.31
16H18N4O
282.33
17H20N4O
296.37
C
C
C
C
C
C
C
16H18N2O2
270.32
17H20N2O2
284.35
18H22N2O2
(298.38)
16H18N2O2
(270.32)
17H20N2O2
(284.35)
18H22N2O2
(298.37)
16H18N2O3
(286.32)
9.96
9.39
9.51
10.36
10.48
9.85
9.96
9.39
150
240
270
225
270
9.51
9.78
9.50

SYNTHESIS OF SPIRO HETEROCYCLIC COMPOUNDS
1305
Table I Analytical and experimental data of the new compounds (Continued)
Analysis (calc./found)
Product
No.
Time of
Reaction
Yield
%
Molecular
Formula
Mp◦C
275
250
95
C%
H%
N%
10b
10c
11a
11b
11c
12a
12b
12c
13a
13b
13c
14a
14b
14c
15a
15b
15c
16a
16b
16c
17a
17b
17c
18a
18b
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
3 h
2 h
2 h
2 h
3 h
3 h
50
45
60
65
60
60
70
70
50
60
45
60
65
50
60
65
70
60
50
C17H20N2O3
(300.35)
67.98
67.81
68.77
68.55
78.05
78.22
78.41
78.55
78.72
78.86
69.11
69.00
70.01
70.13
70.82
70.67
64.58
64.41
65.66
65.80
66.64
66.49
59.97
59.79
61.28
61.06
62.47
62.61
78.92
78.71
79.22
79.36
79.49
79.31
73.01
73.16
73.74
73.85
74.38
74.21
73.33
73.45
74.04
74.91
74.67
74.52
71.61
71.45
72.52
72.69
6.70
6.51
7.05
7.19
6.89
7.07
7.23
7.11
7.54
7.41
7.04
7.19
7.44
7.55
7.79
7.65
6.19
6.33
6, 61
6.49
6.98
6.72
6.19
6.01
6.61
6.77
6.98
6.72
6.62
6.51
6.96
7.12
7.27
7.45
7.88
7.72
8.25
8.03
8.57
8.42
8.35
8.45
8.69
8.86
9.00
8.87
7.51
7.39
7.95
8.20
9.33
9.45
8.91
9.25
9.58
9.45
9.14
9.28
8.74
C
18H22N2O3
(314.38)
C
19H20N2O
(292.37)
120
132
135
140
105
120
180
130
200
185
220
127
240
145
110
137
130
180
175
205
190
135
C
20H22N2O
(306.40)
C
C
C
C
21H24N2O
(320.42)
14H17N3O
(243.30)
15H19N3O
(257.32)
16H21N3O
(271.35)
8.85
17.27
17.12
16.32
16.43
15.48
15.61
10.76
10.87
10.21
10.02
9.71
C
C
C
14H16N2OS
(260.35)
15H18N2OS
(274.38)
16H20N2OS
(288.40)
9.93
C
13H16N4S
(260.35)
14H18N4S
(274.38)
15H20N4S
(288.40)
21.52
21.67
20.41
20.22
19.42
19.50
9.20
9.07
8.79
8.90
8.42
C
C
C
C
C
C
C
C
20H20N2O
(304.38)
21H22N2O
(318.41)
22H24N2O
(332.43)
14H18N2O
(230.31)
15H20N2O
(244.32)
16H22N2O
(258.35)
8.56
12.16
12.01
11.46
1160
10.84
10.62
18.32
18.11
17.27
17.00
16.32
16, 03
20.87
20.73
19.52
19.67
50
70
C
14H19N3
70
65
(229.31)
C
15H21N3
(243.34)
C
16H23N3
(257.36)
70
80
C
12H15N3
(201.26)
C
13H17N3
(215.29)
(Continued on next page)

1306
A. M. SOLIMAN ET AL.
Table I Analytical and experimental data of the new compounds (Continued)
Analysis (calc./found)
Product
No.
Time of
Reaction
Yield
%
Molecular
Formula
Mp◦C
140
210
220
197
85
C%
H%
N%
18c
19a
19b
19c
20
3 h
3 h
3 h
3 h
2 h
7 h
85
90
85
70
70
50
C14H19N3
(229.31)
73.33
73.15
71.26
71.48
72.19
72.02
73.01
73.20
60.41
60.53
67.80
75.66
8.34
8.11
6.97
6.80
7.45
7.66
7.87
7.61
6.51
6.67
7.88
7.60
18.32
18.43
13.85
13.70
12.95
13.16
12.16
12.03
10.03
10.22
24.33
24.63
C
12H14N2O
(202.25)
C
C
13H16N2O
(216.27)
14H18N2O
(230.30)
C
14H18N2O2S
(278.36)
21
140
C
13H18N4
(230.31)
The reaction of compounds 1a–c with halo compounds including 2-bromo-1-
phenylethanone, 2-chloroethanol, or 2-aminoethanol in POCl3 was carried out, where we
were able to isolate the corresponding spiro products 15a–c, 16a–c, or 17a–c, respectively
(see Scheme 3, Tables I and II).
The prepared substrates 1-(2-aminophenyl)aminocyclohexane-1-carboniles 2a–c or
1-(2-hydroxyphenyl)aminocycloalkane-1-carbonitriles 3a–c were allowed to undergo an
intramoleculare nucleophilic addition with subsequent cyclization by boiling in p-xylene
or dioxan in the presence of TEA as catalyst where the corresponding spiro derivatives,
namely, spiro[cycloalkanyl-1ꢁ,2-(3-amino)(1H)-quinoxaline] 18a–c or spiro[cycloalkanyl-
1ꢁ,3-(2-imino)-(4H)-benzoxazine 19a–c, respectively, were obtained in fair yields.
The intramolecular cyclization of 1-(2-methylthiopheyl)aminocyclohexane-1-
carbonitriles 4 was achieved in a two-step reaction. In the first step, compound 4
was oxidized by using H2O2 in acetic acid to give 1-(2-methylsulphonephenyl)-
aminocyclohexane-1-carbonitrile 20, which was allowed in the second step to react
with hydrazine hydrate in absolute ethanol, where spiro ([cycloalkanyl-1ꢁ,2-(3-amino)-
(1H,5H)-1,4,5-benzotriazepine)] 21 was obtained (see Scheme 4, Tables I and II).
EXPERIMENTAL
All melting points were obtained on Melt-Temp II melting point apparatus and were
1
uncorrected. IR spectra were obtained on a Nicolet 710 FT-IR spectrometer. H NMR
spectra were recorded on a Varian EM 360 A at 60 MHz using TMS as an internal standard.
Elemental analyses were performed on a Perkin-Elmer CHN-2400C analyzer model.
Synthesis of 1-Anilinocycloalkanecarbonitrile 1a–c, 1-[(2-Aminophenyl)
amino]cyclopentanecarbonitrile 2a–c, 1-[(2-Hydroxyphenyl)amino]cyclopen-
tanecarbonitrile 3a–c, and 1-{[2-(Methyl thio)phenyl]amino}cyclohexanecar-
bonitrile 4: General Procedure
An equimolar mixture (0.05 mol) of cycloketones (e.g., cyclopentanone, cy-
clohexanone, or cycloheptanone) and proper amines [aniline, benzene-1,2-diamine,
2-aminophenol, or 2-(methylthio)aniline] in cold glacial acetic acid (70 mL) was treated

SYNTHESIS OF SPIRO HETEROCYCLIC COMPOUNDS
1307
Table II Spectral data (IR, 1H NMR) of the new compounds
Comp. No.
IR (KBr) v cm−1
1H-NMR (DMSO-d6) δ ppm
1a
1b
1c
2a
3366 (NH), 3082 (CH-arom.), 2921
(CH-aliph.), 2235 (CN).
3350 (NH), 3044 (CH-arom.), 2932
(CH-aliph.), 2266 (CN).
3362 (NH), 3036 (CH-arom.), 2926
(CH-aliph.), 2235 (CN).
3439, 3377, 3310 (NH2, NH), 3053
(CH-arom.), 2926 (CH- aliph.), 2224
(CN)
7.5–6.8 (m, 5H, CH-arom.), 3.7 (s, 1H, NH),
2.6–1.2 (m, 8H, cyclic CH2).
7.5–6.9 (m, 5H, CH-arom.), 3.75 (s, 1H, NH),
2.6–1.2 (m, 10H, cyclic CH2).
7.6–6.9 (m, 5H, CH-arom.), 3.4 (s, 1H, NH),
2.4–1.5 (m, 12H, cyclic CH2).
7.7–7.0 (m, 4H, CH-arom.), 4.8 (br, 2H, NH2),
3.5 (s, 1H, NH), 2.4–1.3 (m, 8H, cyclic
CH2).
2b
2c
3a
3b
3c
4
3446, 3382.3306 (NH2, NH), 3036
(CH-arom.), 2920 (CH-aliph.), 2232
(CN).
3440, 3372, 3316 (NH, NH2), 3053
(CH-arom.), 2932 (CH-aliph.), 2216
(CN).
7.8–7.1 (m.4H, CH-arom.), 4.8 (br, 2H, NH2),
3.65 (s, 1H, NH), 2.5–1.5 (m, 10H, cyclic
CH2).
7.7–7.0 (m, 4H, CH-arom.), 4.9 (br, 2H, NH2),
3.75 (s, 1H, NH), 2.4–1.2 (m, 12H, cyclic
CH2).
7.2–6.6 (m, 4H, CH-arom.), 4.5 (br, 1H, OH),
3.7 (s, 1H, NH), 2.5–1.6 (m, 8H, cyclic
CH2).
7.2–6.5 (m, 4H, CH-arom.), 4.55 (br, 1H, OH),
3.7 (s, 1H, NH), 2.3–1.3 (m, 10H, cyclic
CH2).
7.1–6.4 (m, 4H, CH-arom.), 4.7 (br, 1H, OH),
3.75 (s, 1H, NH), 2.4–1.2 (m, 12H, cyclic
CH2).
7.6–6.8 (m, 4H, CH-arom.), 5.1 (s, 1H, NH),
2.3 (s, 3H, SCH3)2.1–1.3 (m, 10H, cyclic
CH2).
3300 (OH), 3134 (NH), 3048 (CH-arom.),
2950 (CH-aliph.), 2230 (CN).
3312 (OH), 3171 (NH), (CH-arom.), 2939
(CH-aliph.), 2235 (CN).
3316 (OH), 3193 (NH), 3043 (CH-arom.),
2946 (CH-aliph.), 2225 (CN).
3346 (NH), 3057 (CH-arom.), 2932
(CH-aliph.), 2233 (CN).
5a
5b
5c
3410, 3352, 3220 (NH, NH2), 3052
(CH-arom.), 2953 (CH-aliph.), 2197
(CN).
3435, 3361, 3208 (NH, NH2), 3053
(CH-arom.), 2937 (CH-aliph.), 2197
(CN).
3426, 3335, 3230 (NH, NH2), 3061
(CH-arom.), 2928 (CH-aliph.), 2204
(CN).
9.2 (s, 1H, NH), 7.6–6.8 (m, 5H, CH-arom.),
4.3 (br, 2H, NH2), 2.2–1.4 (m, 8H, cyclic
CH2).
9.1 (s, 1H, NH), 7.8–7.1 (m, 5H, CH-arom.),
5.9 (br, 2H, NH2), 2.2–1.3 (m, 10H, cyclic
CH2).
9.2 (s, 1H, NH), 7.5–6.8 (m, 5H, CH-arom.),
5.3 (br, 2H, NH2), 2.4–1.2 (m, 12H, cyclic
CH2).
6a
6b
6c
7a
7b
7c
8a
8b
8c
3274, 3207 (NH2), 3056 (CH-arom.), 2958
(CH-aliph), 2260 (CN), 1669 (C O).
3273, 3197 (NH2), 3065 (CH-arom.), 2959
(CH-aliph.), 2260 (CN), 1670 (C O).
3277, 3195 (NH2), 3062 (CH-arom.), 2956
(CH-aliph.), 2260 (CN), 1670 (C O).
3406, 3318, 3182 (3NH), 3049 (CH-arom.),
2932 (CH-aliph.), 1666 (C O).
3418, 3326, 3205 (3NH), 3063 (CH-arom.),
2942 (CH-aliph.), 1666 (C O).
3412, 3321, 3214 (3NH), 3058 (CH-arom.),
2924 (CH-aliph), 1668 (C O).
3314, 3215 (NH2), 3065 (CH-arom.), 2945
(CH-aliph.), 1678, 1664 (2C O).
3302, 3205 (NH2), 3055 (CH-arom.), 2926
(CH-aliph.), 1672, 1668 (2C O).
3306, 3209 (NH2), 3056 (CH-arom.), 2930
(CH-aliph.), 1670, 1666 (2C O).
7.8–7.2 (m, 5H, CH, arom.), 3.9 (br, 2H,
NH2), 1.8–1.2 (m, 8H, cyclic CH2).
7.7–7.1 (m, 5H, CH, arom.), 4.2 (br, 2H,
NH2), 1.9–1.2 (m, 10H, cyclic CH2).
7.9–7.2 (m, 5H, CH, arom.), 4.5 (br, 2H,
NH2), 1.8–1.1 (m, 12H, cyclic CH2).
9.4–9.1 (br, 3H, 3NH), 7.8–7.2 (m, 5H,
CH-arom.), 2.1–1.2 (m, 8H, cyclic CH2).
9.5–9.2 (br, 3H, 3NH), 7.7–7.1 (m, 5H,
CH-arom.), 2.2–1.2 (m, 10H, cyclic CH2).
9.3–9.0 (br, 3H, 3NH), 7.7–7.2 (m, 5H,
CH-arom.), 2.4–1.2 (m, 12H, cyclic CH2).
7.8–7.2 (m, 5H, CH-arom.), 5.5 (br, 2H, NH2),
2.2–1.6 (br, 11H, cyclic CH2+COCH3).
7.8–7.4 (m, 5H, CH-arom.), 5.3 (br, 2H, NH2),
2.4–1.8 (br, 13H, cyclic CH2+COCH3).
7.8–7.4 (m, 5H, CH-arom.), 5.6 (br, 2H, NH2),
2.2–1, 6 (br, 15H, cyclic CH2+COCH3).
(Continued on next page)

1308
A. M. SOLIMAN ET AL.
Table II Spectral data (IR, 1H NMR) of the new compounds (Continued)
Comp. No.
IR (KBr) v cm−1
1H-NMR (DMSO-d6) δ ppm
9a
3418 (NH), 3013 (CH-arom.), 2930
(CH-aliph.), 1650 (C O).
10.1 (br, 1H, NH), 8.2–7.6 (m, 5H, CH-arom.),
6.5 (s, 1H, CH), 2.2–1.8 (br, 11H, cyclic
CH2+CH3).
9b
9c
3416 (NH), 3042 (CH-arom.), 2930
(CH-aliph.), 1666 (C O).
9.8 (br, 1H, NH), 7.7–7.2 (m, 5H, CH-arom.),
6.2 (s, 1H, CH), 2.4–1.3 (br, 13H,
cyclicCH2+CH3).
3439 (NH), 3035 (CH-arom.), 2924
(CH-aliph.), 1649 (C O).
9.6 (br, 1H, NH), 7.7–7.1 (m, 5H, CH-arom.),
6.3 (s, 1H, CH), 2.6–1.4 (br, 15H, cyclic
CH2+CH3).
10a
10b
10c
11a
3416, 3320 (NH2), 3057 (CH-arom.), 2926
(CH-aliph.), 1732, 1660 (2CO).
3427, 3332 (NH2), 3055 (CH-arom.), 2937
(CH-aliph.), 1732, 1660 (2CO).
3417, 3330 (NH2), 3065 (CH-arom.), 2934
(CH-aliph.), 1724, 1666 (2CO).
3391 (NH), 3036 (CH-arom.), 2920
(CH-aliph.).
7.8–7.3 (m, 5H, CH-arom.), 5.5 (br, 2H, NH2),
2.4–18 (br, 11H, cyclic CH2+CH3 ester).
7.8–7.3 (m, 5H, CH-arom.), 5.6 (br, 2H, NH2),
2.2–1.6 (br, 13H, cyclic CH2+CH3ester).
7.7–7.2 (m, 5H, CH-arom.), 5.4 (br, 2H, NH2),
2.1–1.4 (br, 15H, cyclic CH2+CH3 ester).
10.2 (br, 1H, NH), 7.7–7.1 (m, 10H,
CH-arom.), 4.8 (s, 1H, CH-ph), 2.2–1.4 (m,
8H, cyclic CH2).
11b
11c
12a
12b
12c
13a
13b
13c
14a
14b
14c
15a
3337 (NH), 3049 (CH-arom.), 2936
(CH-aliph.).
10.1 (br, 1H, NH), 7.8–7.2 (m, 10H,
CH-arom.), 4.6 (s, 1H, CH-ph), 2.2–1.6 (m,
10H, cyclic CH2).
9.8 (br, 1H, NH), 7.6–7, 0 (m, 10H,
CH-arom.), 4.8 (s, 1H, CH-ph), 2.4–1.6 (m,
12H, cyclic CH2).
7.8–7.2 (m, 5H, CH-arom), 4.7 (br, 2H, NH2),
4.2 (s, 2H, CH2 pyrazine), 1.9–1.2 (m, 8H,
cyclic CH2).
8.0–7.2 (m, 5H, CH-arom), 4.4 (br, 2H, NH2),
4.0 (s, 2H, CH2 pyrazine), 2.2–1.4 (m, 10H,
cyclic CH2).
7.7–7.1 (m, 5H, CH-arom), 4.4 (br, 2H, NH2),
3.9 (s, 2H, CH2 pyrazine), 2.1–1.6 (m, 12H,
cyclic CH2).
9.8 (br, 1H, NH), 7.7–7.1 (m, 5H, CH-arom.),
4.2 (s, 2H, CH2 thiazine), 1.9–1.1 (m, 8H,
cyclic CH2).
9.6 (br, 1H, NH), 7.6–7.1 (m, 5H, CH-arom.),
4.0 (s, 2H, CH2 thiazine), 2.1–1.2 (m, 10H,
cyclicCH2).
9.8 (br, 1H, NH), 7.6–7.2 (m, 5H, CH-arom.),
4.1 (s, 2H, CH2 thiazine), 2.1–1.3 (m, 12H,
cyclic CH2).
9.9 (br, 1H, NH), 7.6–7.1 (m, 5H, CH-arom.),
5.9 (br, 2H, NH2), 2.6–1.5 (m, 8H, cyclic
CH2).
9.8 (br, 1H, NH), 7.8–7.0 (m, 5H, CH-arom.),
6.1 (br, 2H, NH2), 2.5–1.5 (m, 10H, cyclic
CH2).
10.1 (br, 1H, NH), 8.0–7.3 (m, 5H, CH-arom.),
5.4 (br, 2H, NH2), 2.3–1.6 (m, 12H, cyclic
CH2).
9.5 (br, 1H, NH), 7.6–7.2 (m, 11H, CH-arom.,
CH), 2.2–1.6 (m, 8H, cyclicCH2).
3342 (NH), 3055 (CH-arom.), 2936
(CH-aliph.).
3402, 3300 (NH2), 3055 (CH-arom.), 2920
(CH-aliph.), 1676 (CO).
3258, 3175 (NH2), 3049 (CH-arom.), 2926
(CH aliph.), 1682 (CO).
3381, 3269 (NH2), 3060 (CH-arom.), 2939
(CH-aliph.), 1682 (CO).
3364 (NH), 3056 (CH-arom.), 2953
(CH-aliph.), 1668 (CO).
3414 (NH), 3055 (CH-arom.), 2930
(CH-aliph.), 1678 (CO).
3416 (NH), 3049 (CH-arom.), 2928
(CH-aliph.), 1665 (CO).
3435, 3306, 3181 (NH, NH2), 3055
(CH-arom.), 2951 (aliph.).
3418, 3258, 3165 (NH, NH2), 3056
(CH-arom.), 2924 (CH-aliph.).
3410, 3320, 3230 (NH, NH2), 3046
(CH-arom.), 2936 (CH-aliph.).
3430 (NH), 3049 (CH-arom.), 2910
(CH-aliph.).

SYNTHESIS OF SPIRO HETEROCYCLIC COMPOUNDS
1309
Table II Spectral data (IR, 1H NMR) of the new compounds (Continued)
Comp. No.
15b
IR (KBr) v cm−1
1H-NMR (DMSO-d6) δ ppm
3400 (NH), 3061 (CH-arom.), 2930
(CH-aliph.).
3397 (NH), 3062 (CH-arom.), 2926
(CH-aliph.).
3329 (NH), 3054 (CH-arom.), 2937
(CH-aliph.).
9.8 (br, 1H, NH), 7.7–7.1 (m, 11H, CH-arom.,
CH), 2.0–1.4 (m, 10H, cyclic CH2).
9.6 (br, 1H, NH), 7.8–7.2 (m, 11H, CH-arom.,
CH), 2.9–1.4 (m, 12H, cyclic CH2).
8.8 (br, 1H, NH), 7.6–6.9 (m, 5H, CH-arom.),
3.8 (br, 4H, 2CH2), 1.9–1.1 (m, 8H, cyclic
CH2).
15c
16a
16b
16c
17a
17b
17c
18a
18b
18c
3410 (NH), 3053 (CH-arom.), 2930
(CH-aliph).
9.1 (br, 1H, NH), 7.8–7.2 (m, 5H, CH-arom.),
4.0 (br, 4H, 2CH2), 2.1–1.4 (m, 10H, cyclic
CH2).
9.3 (br, 1H, NH), 7.8–7.1 (m, 5H, CH-arom.),
4.0 (br, 4H, 2CH2), 2.2–1.6 (m, 12H, cyclic
CH2).
7.8–7.2 (m, 5H, CH, arom.), 4.5 (br, 2H,
NH2), 3.8 (br, 4H, 2CH2), 2.6–1.8 (m, 8H,
cyclic CH2).
7.7–7.2 (m, 5H, CH-arom.), 4.6 (br, 2H, NH2),
3.9 (br, 4H, 2CH2), 2.5–1.6 (m, 10H, cyclic
CH2).
8.0–7.2 (m, 5H, CH-arom.), 5.1 (br, 2H, NH2),
4.0 (br, 4H, 2CH2), 2.6–1.6 (m, 12H, cyclic
CH2).
8.6 (s, 1H, NH), 7.8–7.2 (m, 4H, CH-arom.),
5.2 (s, 2H, NH2), 1.9–1.5 (m, 8H, cyclic
CH2).
8.7 (s, 1H, NH), 7.8–7.3 (m, 4H, CH-arom.),
5.0 (s, 2H, NH2), 2.0–1.6 (m, 10H, cyclic
CH2).
8.6 (s, 1H, NH), 7.6–6.9 (m, 4H, CH-arom.),
4.8 (s, 2H, NH2), 2.1–1.6 (m, 12H, cyclic
CH2).
3418 (NH), 3056 (CH-arom.), 2943
(CH-aliph.).
3418, 3309 (NH2), 3055 (CH-arom.), 2937
(CH-aliph.).
3418, 3316 (NH2), 3061 (CH-arom.), 2926
(CH-aliph.).
3416, 3308 (NH2), 3041 (CH-arom.), 2941
(CH-aliph.).
3450, 3335, 3312 (NH, NH2), 3050
(CH-arom.), 2930 (CH-aliph.).
3450, 3352, 3265 (NH, NH2), 3044
(CH-arom.), 2926 (CH-aliph.)
3460, 3337, 3250 (NH, NH2), 3057
(CH-arom.), 2953 (CH-aliph.).
19a
19b
3397, 3150 (2NH), 3061 (CH-arom.), 2955
(CH-aliph.).
3327, 3246 (2NH), 3061 (CH-arom.), 2939
(CH-aliph.).
7.8–6.8 (m, 4H, CH-arom.), 5.0 (br, 1H, NH),
3.5 (br, 1H, NH), 2.3–1.6 (m, 8Hcyclic CH2)
7.0–6.4 (m, 4H, CH-arom.), 4.6 (br, 1H, NH),
3.4 (br, 1H, NH), 2.0–1.5 (m, 10H, cyclic
CH2)
19c
20
3337, 3255 (2NH), 3059 (CH-arom.), 2946
(CH-aliph.).
7.8–7.0 (m, 4H, CH-arom.), 4.7 (br, 1H, NH),
3.7 (br, 1H, NH), 1.9–1.5 (m, 12H, cyclic
CH2)
7.6–7.0 (m, 4H, CH-arom.), 5.1 (br, 1H, NH),
2.9 (s, 3H, CH3), 2.0–1.3 (m, 10H, cyclic
CH2).
3354 (NH), 3060 (CH-arom.), 2936
(CH-aliph.), 2224 (CN), 1313, 1128
(SO2).
21
3450, 3416, 3352, 3256 (2NH, NH2), 3046
(CH-arom.), 2946 (CH-aliph.).
9.7 (br, 2H, 2NH), 7.8–7.0 (m, 4H, CH-arom),
5.4 (s, 2H, NH2), 2.1–1.5 (m, 10H, cyclic
CH2).
with sodium cyanide (0.05 mol) in small portions under stirring. After addition, the stirring
was continued for 1 h at room temperature. The reaction mixture was then poured into
ice-cold water. The precipitated solid was filtered off, washed with water, and recrystallized
from aqueous ethanol into shining crystals.

1310
A. M. SOLIMAN ET AL.
Scheme 3
Synthesis of Spiro[cycloalkanyl-1ꢀ,2-pyrrole]derivatives 5a–c, 7a-c, 8a–c,
9a–c, Spiro[cycloalkanyl-1ꢀ,2-pyrrolo(3,4-c)pyrazole] Derivatives 6a–c, and
Spiro[cyclo-alkanyl-1ꢀ,4-oxazepine)] Derivatives 10a–c: General Procedure
A mixture of compound 1a, 1b, or 1c (0.01 mol) and triethylamine (TEA) (1 mL)
was gradually added to a stirred suspension of the appropriate active methylene reagent
(0.01 mol) in DMF, p-xylene, or diphenylether (20 mL) (Scheme II). The reaction mixture

SYNTHESIS OF SPIRO HETEROCYCLIC COMPOUNDS
1311
Scheme 4
was refluxed over different periods of time (1–3 h) and was then concentrated. After cooling,
the precipitated solid was filtered off and recrystallized from the proper solvent.
Spiro[cyclopentanyl-1ꢀ,2-(3-amino-4-cyano-5-imino-1-phenyl)pyrrole]
5a, spiro[cyclohexanyl-1ꢀ,2-(3-amino-4-cyano-5-imino-1-phenyl)pyrrole] 5b,
and
spiro[cyclo-heptanyl-1ꢀ,2-(3-amino-4-cyano-5-imino-1-phenyl)pyrrole]
5c. The reaction mixture of compound 1a, 1b, or 1c with malononitrile in DMF (20 mL)
was refluxed for 3 h. The solid product was filtered off and recrystallized from petroleum
ether (60:80) into colorless crystals.

1312
A. M. SOLIMAN ET AL.
Spiro[cyclopentanyl-1ꢀ,2-(3-amino-4-cyano-1-phenyl)pyrrol-5-one] 6a,
spiro[cyclohexanyl-1ꢀ,2-(3-amino-4-cyano-1-phenyl)pyrrol-5-one 6b, and Spi
rocycloheptanyl-1ꢀ,2-(3-amino-4-cyano-1-phenyl)pyrrol-5-one] 6c. The reaction
mixture of compound 1a, 1b, or 1c with ethylcyanoacetate in DMF (20 mL) was refluxed
for 3 h. The solid product was filtered off and recrystallized from aqueous ethanol into
pink crystals.
Spiro[cyclopentanyl-1ꢀ,2-(5-imino-1-phenyl)pyrrolo(3,4-c)pyrazol(1H,2H)-
5-one]7a, spiro[cyclohexanyl-1ꢀ,2-(5-imino-1-phenyl)pyrrolo(3,4-c)pyrazol(1H,
2H)-5-one] 7b, and spirocycloheptanyl-1ꢀ,2-(5-imino-1-phenyl)pyrrolo (3, 4-c)
pyrazol (1H, 2H)-5-one] 7c. The reaction mixture of compound 1a, 1b, or 1c with
cyanoacetohydrazide in DMF (20 mL) was refluxed for 3 h. The solid product was filtered
off and recrystallized from aqueous ethanol into yellow crystals.
Spiro[cyclopentanyl-1ꢀ,2-(3-amino-4-carbmethoxy-1-phenyl)pyrrol-5-
one] 8a, spiro[cyclohexanyl-1ꢀ,2-(3-amino-4-carbmethoxy-1-phenyl)pyrrol-5-
one 8b, and spiro[cycloheptanyl-1ꢀ,2-(3-amino-4-carbmethoxy-1-phenyl)
pyrrol-5-one] 8c. The reaction mixture of compound 1a, 1b, or 1c along with ethylace-
toacetate in DMF (20 mL) was refluxed for 3 h. The solid product obtained was filtered off
and recrystallized from ethanol into white crystals.
Spiro[cyclopentanyl-1ꢀ,2-(4-acetyl-3-amino-1-phenyl)pyrrol-5-one] 9a,
spiro[cyclohexanyl-1ꢀ,2-(4-acetyl-3-amino-1-phenyl)pyrrol-5-one 9b, and
spiro[cycloheptanyl-1ꢀ,2-(4-acetyl-3-amino-1-phenyl)pyrrol-5-one] 9c. A mix-
ture of compound 1a, 1b, or 1c with ethylacetoacetate in diphenylether (20 mL) was
refluxed for 3 h, then the reaction mixture was evaporated in vacuo. Upon cooling, the
residual mass was extracted with petroleum ether (40:60) (50 mL), and the ethereal
extracted layer was evaporated. The obtained solid was recrystallized from ethanol into
brown crystals.
Spiro[cyclopentany-1ꢀ,3-(2-imino-4–7-methyl-4-phenyl)-1,4-oxazepin-5-
one] 10a, spiro[cyclohexanyl-1ꢀ,3-(2-imino-7-methyl-1-phenyl)-1,4-oxazepin-
5-one 10b, and spiro[cycloheptanyl-1ꢀ,3-(2-imino-7-methyl-1-phenyl)-1,4-
oxazepin-5-one] 10c. The reaction mixture of compound 1a, 1b, or 1c with
dimethylmalonate in p-xylene (20 mL) was refluxed for 3 h. The solid product was filtered
off and recrystallized from ethanol into white crystals.
Synthesis of spiro[cyclopentanyl-1ꢀ,4-(2,3-diphenyl-5-imino)1,3-oxazo
lidine] 11a, spiro[cyclohexanyl-1ꢀ,4-(2,3-diphenyl-5-imino)-1,3-oxazolidine]
11b, and spiro[cycloheptanyl-1ꢀ,4-(2,3-diphenyl-5-imino)-1,3-oxazolidine 11c.
The titled products were obtained by adding compound 1a, 1b, or 1c (0.01 mol) to a stirred
mixture of benzaldehyde (0.01 mol) and a catalytic amount of TEA in ethanol (30 mL).
The reaction mixture was refluxed for 3 h, then concentrated, and the solid product was
filtered off and recrystallized from ethanol into brown crystals.
Synthesis of spiro[cyclopentanyl-1ꢀ,2-(3-amino-1-phenyl)pyrazinolidin-
6-one] 12a, spiro[cyclohexanyl-1ꢀ,2-(3-amino-1-phenyl)pyrazinolidin-6-one]
12b, and spiro[cycloheptanyl-1ꢀ,2-(3-amino-1-phenyl)pyrazinolidin-6-one]
12c. An equimolar mixture of compound 1a, 1b, or 1c and ethyl glyccinate hydrochloride
(0.01 mol) in DMF (30 mL) was treated with TEA (0.012 mol). The reaction mixture was
refluxed for 3 h, concentrated to its half volume, and poured into ice-cold water. The crude
solid was filtered off and recrystallized from ethanol into reddish brown crystals.

SYNTHESIS OF SPIRO HETEROCYCLIC COMPOUNDS
1313
Synthesis of spiro[cyclopentanyl-1ꢀ,3-(2-amino)thiazinolidin-5-one] 13a,
spiro[cyclohexanyl-1ꢀ,3-(2-amino)thiazinolidin-5-one] 13b, and spiro[cyclohe-
ptanyl-1ꢀ,3-(2-amino)thiazinolidin-5-one] 13c. An equimolar mixture (0.01 mol) of
compound 1a, 1b, or 1c and ethyl mercaptoacetate (0.01 mol) in p-xylene (30 mL) was
treated with a catalytic amount of TEA. The reaction mixture was refluxed for 3 h and
evaporated in vacuo. The residual mass was extracted with petroleum ether (40:60) (50
mL), and the ethereal extracted layer was evaporated. The solid product obtained was
recrystallized from ethanol into pink crystals.
Spiro[cyclopentanyl-1ꢀ,5-(2-amino-6-imino-4-phenyl)-1,3,4-thiadiazine]
14a, spiro[cyclohexanyl-1ꢀ,5-(2-amino-6-imino-4-phenyl)-1,3,4-thiadiazine
14b, and spiro[cycloheptanyl-1ꢀ,5-(2-amino-6-imino-4-phenyl) thiadiazine
14c. Compound 1a, 1b, or 1c (0.01 mol) and thiosemicarbazide (0.01 mol) in DMF (30
mL) was treated with a catalytic amount of TEA. The reaction mixture was refluxed for 3h,
allowed to cool, and then poured into ice-cold water. The solid so formed was collected by
filtration and recrystallized from ethanol into brown crystals.
Synthesis of spiro[cyclopentanyl-1ꢀ,3-(4,6-diphenyl-2-imino)-1,4-oxaz-
ine] 15a, spiro[cyclohexanyl-1ꢀ,3-(4,6-diphenyl-2-imino)-1,4-oxazine] 15b, and
spiro[cycloheptanyl-1ꢀ,3-(4,6-diphenyl-2-imino)-1,4-oxazine] 15c. A mixture of
compound 1a, 1b, or 1c (0.01 mol) and phenacyl bromide (0.01 mol) in p-xylene (30 mL)
was treated with TEA (0.012 mol) and was refluxed for 3 h. The reaction mixture was
concentrated in vacuo, and the obtained solid was filtered off, washed with water, and
recrystallized from ethanol into white crystals.
Synthesis of spiro[cyclopentanyl-1ꢀ,3-(2-imino-4-phenyl)-5,6dihydro-
1,4-oxazine] 16a, spiro[cyclohexanyl-1ꢀ,3-(2-imino-4-phynyl)-5,6-dihydro-1,
4-oxazine] 16b, and spiro[cycloheptanyl-1ꢀ,3-(-2-imino-4-phenyl)-5,6-dihydro-
1,4-oxazine] 16c. An equimolar mixture of compound 1a, 1b, or 1c and 2-chloroethanol
(0.01 mol) in dioxane (30 mL) was treated with TEA (0.012 mol). The reaction mixture
was refluxed for 3 h and concentrated. The precipitated solid was filtered off, washed with
water, and recrystallized from methanol into brown crystals.
Synthesis of spiro[cyclopentanyl-1ꢀ,2-(3-amino-1-phenyl)piprazin-3-
ene] 17a, spiro[cyclohexanyl-1ꢀ,2-(3-amino-1-phynyl)piprazin-3-ene]17b, and
spiro[cycloheptanyl-1ꢀ,2-(3-amino-1-phenyl)piprazin-3-ene] 17c. The titled
products were obtained by reacting an equivalent amounts of compound 1a, 1b, or 1c
(0.01 mol) with ethanol amine (0.01 mol) in POCl3 (20 mL). The reaction mixture was
refluxed for 2 h. Upon cooling, it was poured into ice-cold water. The precipitated solid
was filtered off and recrystallized from ethanol into brown crystals.
Synthesis of spiro[cyclopentanyl-1ꢀ,2-(3-amino)(1H)-quinoxaline] 18a,
synthesis of spiro[cyclohexanyl-1ꢀ,2-(3-amino)(1H)-quinoxaline] 18b, and
synthesis of spirocycloheptanyl-1ꢀ,2-(3-amino)(1H)-quinoxaline] 18c. Com-
pound 2a, 2b, or 2c (0.01 mol) in p-xylene (30 mL) was allowed to reflux for 3 h. Upon
cooling, the precipitated solid was filtered off and recrystallized from ethanol into yellow
crystals.
Synthesis of spiro[cyclopentanyl-1ꢀ,2-(2-imino)(4H)-bezoxazine] 19a,
synthesis of spiro[cyclohexanyl-1ꢀ,2-(2-imino)(4H)-benzoxazine] 19b, and
synthesis of spiro [cycloheptanyl-1ꢀ, 2- (2-imino) (4H)-benzoxazine] 19c.
Compound 3a, 3b, or 3c (0.01 mol) in p-xylene (30 mL) was allowed to reflux for 3 h.

1314
A. M. SOLIMAN ET AL.
Upon cooling, the precipitated solid was filtered off and recrystallized from ethanol into
pale yellow crystals.
Synthesis of 1-(2-methylsulphonephenyl)aminocyclohexane-1-carbon-
itrile 20. Compound 4 (0.02 mol) was dissolved in a mixture of glacial acetic acid (2 mL)
and H2O2 (15 mL). The reaction mixture was heated at 70–80 ◦C for 2 h and cooled. The
reaction mixture was then poured into crushed ice. The precipitated product was filtered
off and recrystallized from aqueous ethanol into colorless crystals.
Synthesis of spiro[cyclohexanyl-1ꢀ-2-(3-amino)(1-H,5H)-1,4,5-benzotria-
zepine] 21. A mixture of compound 20 (0.01 mol) and hydrazine (0.01 mol) in dioxane
(30 mL) was refluxed for 7 h. Dioxane was evaporated in vacuo, and the residual mass was
extracted with ether (45 mL). The ethereal extracted layer was evaporated, and the solid
product was recrystallized from ethanol into brown crystals.
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