Hydrogen-bonding patterns in three substituted N-benzyl-N-(3-tert-butyl-1- phenyl-1H-pyrazol-5-yl)acetamides

Article abstract of DOI:10.1107/S0108270110006244

The mol-ecules of N-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-2-chloro-N-(4- methoxy-benz-yl)acetamide, C₂₃H₂₆ClN₃O ₂, are linked into a chain of edge-fused centrosymmetric rings by a combination of one C - H...O hydrogen bond and one C - H...π(arene) hydrogen bond. In N-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-2-chloro-N-(4- chloro-benz-yl)acetamide, C₂₂H₂₃Cl₂N ₃O, a combination of one C - H...O hydrogen bond and two C - H...π(arene) hydrogen bonds, which utilize different aryl rings as the acceptors, link the mol-ecules into sheets. The mol-ecules of S-[N-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-N-(4-methyl-benz-yl)carbamo-yl] methyl O-ethyl carbonodithio-ate, C₂₆H₃₁N ₃O₂S₂, are also linked into sheets, now by a combination of two C - H...O hydrogen bonds, both of which utilize the amide O atom as the acceptor, and two C - H...π(arene) hydrogen bonds, which utilize different aryl groups as the acceptors.

Full text of DOI:10.1107/S0108270110006244

organic compounds
Acta Crystallographica Section C
Crystal Structure
Communications
acetamide intermediates, namely N-(3-tert-butyl-1-phenyl-1H-
pyrazol-5-yl)-2-chloro-N-(4-methoxybenzyl)acetamide, (I),
and N-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-2-chloro-N-(4-
chlorobenzyl)acetamide, (II), and one carbonodithioate
intermediate, S-[N-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-N-
(4-methylbenzyl)carbamoyl]methyl O-ethyl carbonodithioate,
(III), all of which have interesting patterns of hydrogen
bonding in their crystal structures. We compare the molecular
structures, particularly the molecular conformations, of com-
pounds (I)–(III) with that of the simple acetamide N-(3-tert-
butyl-1-phenyl-1H-pyrazol-5-yl)-N-(4-methoxybenzyl)aceta-
mide, (IV), whose structure was reported recently (Castillo et
al., 2010), and we also compare the hydrogen bonding in (I)
with that in (IV).
ISSN 0108-2701
Hydrogen-bonding patterns in three
substituted N-benzyl-N-(3-tert-butyl-
1-phenyl-1H-pyrazol-5-yl)acetamides
a
a
a
´
Gerson Lopez, L. Marina Jaramillo, Rodrigo Abonia,
Justo Cobob and Christopher Glidewellc*
a
´
Departamento de Quımica, Universidad de Valle, AA 25360 Cali, Colombia,
b
´
´
´
´
Departamento de Quımica Inorganica y Organica, Universidad de Jaen, 23071
Jaen, Spain, and cSchool of Chemistry, University of St Andrews, Fife KY16 9ST,
´
Scotland
Correspondence e-mail: cg@st-andrews.ac.uk
Received 16 February 2010
Accepted 16 February 2010
Online 6 March 2010
The molecules of N-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-
2-chloro-N-(4-methoxybenzyl)acetamide, C23H26ClN3O2, are
linked into a chain of edge-fused centrosymmetric rings by
a combination of one C—HÁ Á ÁO hydrogen bond and one
C—HÁ Á Áꢀ(arene) hydrogen bond. In N-(3-tert-butyl-
1-phenyl-1H-pyrazol-5-yl)-2-chloro-N-(4-chlorobenzyl)aceta-
mide, C22H23Cl2N3O, a combination of one C—HÁ Á ÁO
hydrogen bond and two C—HÁ Á Áꢀ(arene) hydrogen bonds,
which utilize different aryl rings as the acceptors, link the
molecules into sheets. The molecules of S-[N-(3-tert-butyl-1-
phenyl-1H-pyrazol-5-yl)-N-(4-methylbenzyl)carbamoyl]methyl
O-ethyl carbonodithioate, C26H31N3O2S2, are also linked into
sheets, now by a combination of two C—HÁ Á ÁO hydrogen
bonds, both of which utilize the amide O atom as the acceptor,
and two C—HÁ Á Áꢀ(arene) hydrogen bonds, which utilize
different aryl groups as the acceptors.
Comment
Fused pyrazole derivatives have a wide range of potential
applications (Elguero, 1984, 1996) and, in connection with a
synthetic study of new routes to such compounds, we report
here the structure of three new compounds, (I)–(III) (Figs. 1–
3), prepared as intermediates in a synthetic pathway designed
to produce fused pyrazole compounds from alkyl xanthate
derivatives via free-radical cyclization processes (Binot et al.,
Compounds (I) and (II) differ only in the identity of the
4-substituent in the benzyl unit, viz. methoxy in compound (I)
and chloro in compound (II), but despite this rather small
change of substituent, these two compounds crystallize in
different crystal systems, viz. triclinic for (I) and monoclinic
for (II). Similarly, the pattern of the intermolecular hydrogen
bonds is different in (I) and (II) leading to different forms of
supramolecular aggregation, as discussed below, despite the
fact that in neither compound does the substituent in question
play any direct role in the intermolecular interactions.
Compounds (I) and (IV) (Castillo et al., 2010) are even closer
in similarity, differing only by the replacement of one of the
acetyl H atoms in (IV) by a Cl atom in (I); these two
compounds crystallize in the same space group, P1, with unit-
cell volumes which differ by less than 1%, while the corre-
´
2003; Bacque et al., 2004; Ibarra-Rivera et al., 2007). In this
synthetic sequence (see scheme), benzyl-substituted N-benzyl-
N-(3-tert-butyl-1-phenyl-1H-pyrazol-5-yl)-2-chloroacetamides
are prepared by reaction of the corresponding 5-benzylamino-
3-tert-butyl-1-phenyl-1H-pyrazoles with chloroacetyl chloride,
followed by reaction with potassium O-ethyl carbonodithioate
to introduce the alkyl xanthate moiety. We report here the
molecular and supramolecular structures of two chloro-
o168 # 2010 International Union of Crystallography
doi:10.1107/S0108270110006244
Acta Cryst. (2010). C66, o168–o173

organic compounds
Figure 1
The molecular structure of compound (I), showing the atom-labelling
scheme. Displacement ellipsoids are drawn at the 30% probability level.
Figure 3
The molecular structure of compound (III), showing the atom-labelling
scheme. Displacement ellipsoids are drawn at the 30% probability level.
enantiomer and the hydrogen-bonded structures of (I) and
(IV) are significantly different.
The molecular conformations of compounds (I)–(III) can,
apart from the carbonodithioate portion of compound (III),
be defined in terms of a rather small number of torsion angles,
and Table 1 lists the values of these angles along with the
corresponding values for compound (IV) (Castillo et al., 2010).
It is immediately evident that all four compounds adopt very
similar conformations for their common fragments, with the
exception of the orientation of the tert-butyl groups. In each of
(I)–(IV), one methyl C atom of the tert-butyl group, denoted
C32 in each case, lies close to, but not in the plane of, the
adjacent pyrazole ring. However, while in compounds (I) and
(IV) atom C32 lies remote from the ring atom N2, in
compounds (II) and (III) this atom lies close to N2 (Figs. 1–3
and Table 1). The tert-butyl group has local threefold rota-
tional symmetry, and in compounds (I)–(IV) it is bonded
directly to a planar pyrazole ring; hence the rotational barriers
about the bonds C3—C31 approximate to sixfold barriers and,
as such, they are expected to be very low, providing essentially
no intramolecular hindrance to rotation about this bond. In
addition, there are no direction-specific intermolecular inter-
actions present which might provide intermolecular hindrance
to such a rotation. Indeed this type of rapid rotation of tert-
butyl groups has been observed in a number of systems using
solid-state NMR spectroscopy (Riddell & Rogerson, 1996,
1997). Thus, it is possible that the observed orientations of the
tert-butyl groups are determined primarily by the space left
available by the supramolecular aggregation. None of the
molecules of (I)–(III) exhibits any internal symmetry and so
all are conformationally chiral, but in every case the space
group accommodates equal numbers of the two conforma-
tional enantiomers.
Figure 2
The molecular structure of compound (II), showing the atom-labelling
scheme. Displacement ellipsoids are drawn at the 30% probability level.
sponding unit-cell angles differ by less than 2ꢀ. However, unit-
cell vectors a and b are larger for (I) by ca 2.5 and 6.6%, while
the unit-cell vector c is smaller for (I) by ca 7.1%. This degree
of similarity raises the question of whether (I) and (IV) can be
regarded as isomorphous or isostructural; examination of the
atom coordinates for the two compounds shows that the
coordinates of corresponding atoms are approximately related
to one another by the noncrystallographic transformation
(1 À y, 1 À x, 12 À z), but, as discussed below, the two reference
molecules are selected to be the same conformational
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Acta Cryst. (2010). C66, o168–o173
Lopez et al.
C23H26ClN3O2, C22H23Cl2N3O and C26H31N3O2S2 o169

organic compounds
Figure 4
Figure 5
A stereoview of part of the crystal structure of compound (I), showing the
formation of a hydrogen-bonded chain of edge-fused centrosymmetric
rings running parallel to [111]. For the sake of clarity, H atoms not
involved in the motifs shown have been omitted.
A stereoview of part of the crystal structure of compound (II), showing
the formation of a hydrogen-bonded chain of edge-fused centrosym-
metric rings running parallel to [010]. For the sake of clarity, H atoms not
involved in the motifs shown have been omitted.
The supramolecular aggregation in compounds (I)–(III) is
controlled by
a
combination of C—HÁ Á ÁO and C—
HÁ Á Áꢀ(arene) hydrogen bonds (Table 2 where, for each
compound, the C—HÁ Á ÁO hydrogen bonds are listed first).
However, C—HÁ Á ÁN hydrogen bonds and aromatic ꢀ–ꢀ
stacking interactions are absent from the structures of all three
compounds. While amide atom O58 acts as a hydrogen-bond
acceptor in each of (I)–(III), as indeed it does in compound
(IV) also (Castillo et al., 2010), different hydrogen-bond
donors to O58 are active in each of (I)–(III). In compound (I)
only the unsubstituted aryl ring acts as an acceptor of a C—
HÁ Á Áꢀ(arene) hydrogen bond, but in compounds (II) and (III)
both aryl rings accept hydrogen bonds. The hydrogen-bonded
structure of compound (I) is one-dimensional and thus fairly
simple, whereas the hydrogen-bonded structures of com-
pounds (II) and (III) are both two-dimensional and consid-
erably more complex than that of compound (I).
In compound (I), the two independent hydrogen bonds
(Table 2) generate a chain of edge-fused centrosymmetric
rings running parallel to the [111] direction, with R22(16)
(Bernstein et al., 1995) rings built from pairs of C—HÁ Á ÁO
1
hydrogen bonds centred at (n, n, n À ), where n represents an
2
integer, and with the rings built from pairs of C—HÁ Á Á
ꢀ(arene) hydrogen bonds centred at (n + 12, n + 21, n), where n
again represents an integer (Fig. 4).
Figure 6
A stereoview of part of the crystal structure of compound (II), showing
the formation of a hydrogen-bonded chain running parallel to [001]. For
the sake of clarity, H atoms not involved in the motif shown have been
omitted.
The hydrogen-bonded structure of compound (II) takes the
form of a sheet, whose formation is readily analysed using the
substructure approach (Ferguson et al., 1998a,b; Gregson et al.,
2000). Two independent one-dimensional substructures can be
identified in the crystal structure of compound (II). In the first
of these, the combined actions of the C—HÁ Á ÁO hydrogen
bond and the C—HÁ Á Áꢀ(arene) hydrogen bond which utilizes
the unsubstituted aryl ring as the acceptor link molecules
symmetry-related rings running parallel to the [010] direction,
and within which the C—HÁ Á ÁO interaction forms a C(5) chain
(Fig. 5). In the second, and simpler, substructure, a single C—
HÁ Á Áꢀ(arene) hydrogen bond using the substituted aryl ring as
the acceptor links molecules related by the c-glide plane at
y = 14 into a chain running parallel to the [001] direction (Fig. 6).
1
related by the 21 screw axis along (12, y, ) into a chain of
4
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´
o170 Lopez et al. C23H26ClN3O2, C22H23Cl2N3O and C26H31N3O2S2
Acta Cryst. (2010). C66, o168–o173

organic compounds
Figure 8
A stereoview of part of the crystal structure of compound (III), showing
the formation of a hydrogen-bonded chain of edge-fused centrosym-
metric rings running parallel to [100]. For the sake of clarity, H atoms not
involved in the motifs shown have been omitted.
Figure 7
A stereoview of part of the crystal structure of compound (III), showing
the formation of a hydrogen-bonded chain of edge-fused centrosym-
metric rings running parallel to [001]. For the sake of clarity, H atoms not
involved in the motifs shown have been omitted.
the similarity in their unit-cell dimensions. In compound (IV)
(Castillo et al., 2010), a chain of edge-fused centrosymmetric
rings is generated by the combination of one C—HÁ Á ÁO
hydrogen bond and one C—HÁ Á Áꢀ(arene) hydrogen bond,
rather as in compound (I). However, the rings formed by the
C—HÁ Á ÁO hydrogen bond are of R22(20) type in (IV) as
opposed to R22(16) type in (I), and the chain runs parallel to
[100] in (IV), i.e. parallel to the shortest unit-cell edge,
whereas in (I) the chain runs parallel to [111], i.e. parallel to a
body-diagonal of the unit cell.
Although compound (III) crystallizes in the space group P1
with only one symmetry operator other than translation
available, the occurrence in the structure of four independent
hydrogen bonds, each of them linking pairs of molecules
related to one another by inversion (Table 2), permits the
development of a two-dimensional hydrogen-bonded struc-
ture. As with the structure of compound (II), it is convenient
to consider the formation of the sheet structure in compound
(III) in terms of two one-dimensional substructures. The two
C—HÁ Á ÁO hydrogen bonds in the structure of (III) both utilize
the same atom, O58, as the acceptor and, in combination,
these two interactions generate a chain of edge-fused
centrosymmetric rings running parallel to the [001] direction.
Experimental
For the synthesis of compounds (I) and (II), mixtures of chloroacetyl
chloride (0.1 ml, 1.25 mmol), dichloromethane (8 ml) and triethyl-
amine (0.3 ml, 2.15 mmol) were cooled in an ice-water bath under an
argon atmosphere. To each mixture, a solution (0.6 mmol) of the
appropriate 5-benzylamino-3-tert-butyl-1-phenyl-1H-pyrazole [3-tert-
butyl-5-(4-methoxybenzylamino)-1-phenyl-1H-pyrazole for (I) or 3-
tert-butyl-5-(4-chlorobenzylamino)-1-phenyl-1H-pyrazole for (II)] in
dichloromethane (2 ml) was added and each mixture was then left at
room temperature for 10 h. In each case, the solvent was removed
under reduced pressure and the resulting solid product was purified
by column chromatography on silica gel (ethyl acetate/dichloro-
methane gradient) to obtain compound (I) in 86% yield and
compound (II) in 82% yield. Crystals of (I) and (II) suitable for
single-crystal X-ray diffraction were grown by slow evaporation, at
ambient temperature and in air, of solutions in ethanol. For (I):
yellow crystals, m.p. 353 K; MS (70 eV) m/z (%): 411/413 (30/10)
[M+], 226 (43), 121 (100); elemental analysis found: C 67.3, H 6.4,
N 9.8%; C23H26ClN3O2 requires: C 67.1, H 6.4, N 10.2%. For (II):
colourless crystals, m.p. 432 K; MS (70 eV) m/z (%): 419/417/415
(6/34/51) [M+], 368/366 (23/63) [MÀ49], 340/338 (19/52), [MÀPh],
127/125 (29/100) [C7H6Cl], 77 (40) [Ph]; HRMS found: 415.1213,
required for C22H23Cl2N3O: 415.1218.
1
Within this chain, R22(16) rings centred at (12, , n), where n
2
represents an integer, alternate with R22(18) rings centred at
1
2
1
2
(12, , n + ), where n again represents an integer (Fig. 7). The
combination of the R22(18) ring with the centrosymmetric ring
generated by the C—HÁ Á Áꢀ(arene) hydrogen bond involving
the unsubstituted aryl group produces a second chain of edge-
fused centrosymmetric rings, this time running parallel to the
[100] direction. The rings built from pairs of C—HÁ Á ÁÁO
1
1 1
hydrogen bonds are centred at (n + , , ), and those built
2
2 2
from paired C—HÁ Á Áꢀ(arene) hydrogen bonds are centred at
(n, 12, 12), where in each case n represents an integer (Fig. 8). The
formation of two chains of rings parallel to the [100] and [001]
directions, respectively, is sufficient to generate a sheet of
considerable complexity lying parallel to (010). The second
C—HÁ Á Áꢀ(arene) hydrogen bond, in which the substituted
aryl ring acts as the acceptor, lies within this sheet and it can be
regarded as a modest reinforcement of the chain parallel to
[001].
It is of interest briefly to compare the hydrogen-bonded
structures of compounds (I) and (IV), particularly in view of
For the synthesis of compound (III), a solution of N-(3-tert-butyl-
1-phenyl-1H-pyrazol-5-yl)-2-chloro-N-(4-methylbenzyl)acetamide
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Acta Cryst. (2010). C66, o168–o173
Lopez et al.
C23H26ClN3O2, C22H23Cl2N3O and C26H31N3O2S2 o171

organic compounds
(0.49 mmol), prepared as for compounds (I) and (II), and potassium
O-ethyl carbonodithioate (0.73 mmol) in acetonitrile (6 ml) was
stirred at room temperature in the absence of light for 2.5 h. The
solvent was removed under reduced pressure and the residue purified
by column chromatography on silica gel (ethyl acetate/dichloro-
methane gradient) to obtain compound (III) in 94% yield. Yellow
crystals suitable for single-crystal X-ray diffraction were grown by
slow evaporation, at ambient temperature and in air, of a solution in
ethanol (m.p. 359 K). MS (70 eV) m/z (%): 481 (2) [M+], 319 (40),
163 (30), 105 (100); elemental analysis found: C 64.8, H 6.4, N 8.7%,
C26H31N3O2S2 requires: C 64.8, H 6.5, N 8.7%.
Table 2
Hydrogen-bond parameters (A, ) for compounds (I)–(III).
ꢀ
˚
Cg1 represents the centroid of the C11–C16 ring and Cg2 represents the
centroid of the C51–C56 ring.
Compound D—HÁ Á ÁA
D—H HÁ Á ÁA DÁ Á ÁA
D—HÁ Á ÁA
(I)
C55—H55Á Á ÁO58i
0.95
0.95
0.99
0.95
0.95
0.95
0.95
0.95
0.99
2.50
2.70
2.43
2.91
2.77
2.39
2.39
2.91
2.82
3.449 (3) 178
C52—H52Á Á ÁCg1ii
C57—H57BÁ Á ÁO58iii
C16—H16Á Á ÁCg2iv
C56—H56Á Á ÁCg1v
C13—H13Á Á ÁO58vi
C55—H55Á Á ÁO58ii
C52—H52Á Á ÁCg1vii
C61—H61AÁ Á ÁCg2ii
3.562 (3) 152
3.307 (3) 148
3.526 (2) 124
3.514 (2) 136
3.244 (5) 149
3.277 (5) 155
3.632 (5) 133
3.610 (5) 137
(II)
(III)
Compound (I)
Symmetry codes: (i) 2 À x, 2 À y, 1 À z; (ii) 1 À x, 1 À y, Àz; (iii) 1 À x, 12 + y, 21 À z; (iv) x,
1
2
1
2
1
2
À y, À + z; (v) 1 À x, À + y, 12 À z; (vi) 1 À x, 1 À y, 1 À z; (vii) Àx, 1 À y, 1 À z.
Crystal data
C23H26ClN3O2
Mr = 411.92
Triclinic, P1
ꢃ = 116.035 (9)ꢀ
3
˚
V = 1043.4 (2) A
Z = 2
Data collection
˚
a = 10.0761 (12) A
Mo Kꢁ radiation
ꢄ = 0.21 mmÀ1
T = 120 K
0.50 Â 0.26 Â 0.22 mm
Bruker–Nonius KappaCCD
diffractometer
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
Tmin = 0.899, Tmax = 0.981
33228 measured reflections
4792 independent reflections
3328 reflections with I > 2ꢅ(I)
Rint = 0.063
˚
b = 10.5208 (8) A
˚
c = 11.1868 (19) A
ꢁ = 96.546 (7)ꢀ
ꢂ = 95.790 (9)ꢀ
Data collection
Refinement
Bruker–Nonius KappaCCD
diffractometer
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
Tmin = 0.914, Tmax = 0.956
27179 measured reflections
4801 independent reflections
2893 reflections with I > 2ꢅ(I)
Rint = 0.068
R[F2 > 2ꢅ(F2)] = 0.049
wR(F2) = 0.116
S = 1.04
256 parameters
H-atom parameteÀrs3 constrained
˚
Áꢆmax = 0.70 e A
À3
˚
4792 reflections
Áꢆmin = À0.83 e A
Refinement
R[F2 > 2ꢅ(F2)] = 0.055
wR(F2) = 0.154
S = 1.05
266 parameters
H-atom parameteÀrs3 constrained
Compound (III)
Crystal data
˚
Áꢆmax = 0.37 e A
À3
˚
C26H31N3O2S2
Mr = 481.68
Triclinic, P1
ꢃ = 84.977 (9)ꢀ
V = 1258.5 (2) A
Z = 2
4801 reflections
Áꢆmin = À0.31 e A
3
˚
˚
a = 9.6847 (14) A
Mo Kꢁ radiation
ꢄ = 0.24 mmÀ1
T = 120 K
0.42 Â 0.35 Â 0.23 mm
Compound (II)
˚
b = 11.3127 (9) A
˚
c = 12.3425 (12) A
Crystal data
ꢁ = 77.040 (8)ꢀ
ꢂ = 72.789 (9)ꢀ
3
˚
V = 2091.2 (6) A
Z = 4
C22H23Cl2N3O
Mr = 416.33
Monoclinic, P21=c
Mo Kꢁ radiation
ꢄ = 0.33 mmÀ1
T = 120 K
0.35 Â 0.12 Â 0.06 mm
Data collection
˚
a = 10.120 (2) A
b = 10.7732 (18) A
˚
Bruker–Nonius KappaCCD
diffractometer
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
Tmin = 0.901, Tmax = 0.947
24648 measured reflections
4471 independent reflections
2251 reflections with I > 2ꢅ(I)
Rint = 0.148
˚
c = 19.2751 (14) A
ꢂ = 95.662 (9)ꢀ
Table 1
Selected torsion angles (A) for compounds (I)–(IV).
Refinement
˚
R[F2 > 2ꢅ(F2)] = 0.056
wR(F2) = 0.172
S = 1.00
303 parameters
H-atom parameteÀrs3 constrained
(I)
(II)
(III)
(IV)a
˚
Áꢆmax = 0.43 e A
Áꢆmin = À0.35 e A
À3
˚
N2—N1—C11—C12
N2—C3—C31—C32
N1—C5—N51—C57
C5—N51—C57—C51
N51—C57—C51—C52
N1—C5—N51—C58
C5—N51—C58—O58
N51—C58—C59—S59
C58—C59—S59—C60
C59—S59—C60—O60
S59—C60—O60—C61
C60—O60—C61—C62
C53—C54—O54—C541
À140.8 (2) À148.0 (2) À136.1 (4) À133.97 (14)
À173.3 (2) À8.9 (3) 6.5 (5) 172.69 (13)
4471 reflections
À102.5 (3) À104.7 (2) À108.5 (4) À100.84 (15)
À85.6 (3)
106.8 (3)
78.3 (3)
À69.1 (2)
102.4 (2)
76.1 (3)
À87.5 (4)
114.0 (4)
73.1 (4)
À80.52 (15)
118.10 (14)
83.16 (17)
All H atoms were located in difference maps and then treated as
riding atoms in geometrically idealized positions, with C—H
˚
distances of 0.95 (aromatic and pyrazole), 0.98 (CH3) or 0.99 A
À177.9 (2) À179.8 (2) À173.4 (3)
176.99 (13)
169.8 (2)
À75.7 (3)
(CH2), and with Uiso(H) = kUeq(C), where k = 1.5 for the methyl
groups, which were permitted to rotate but not to tilt, and 1.2 for all
other H atoms. The quality of the crystals for compound (III) was
consistently rather low, as indicated by the high value of the merging
index, 0.148, and the lower precision of the geometric parameters as
compared with those for compounds (I) and (II). For each of (I)–
178.7 (2)
À175.4 (3)
À180.0 (3)
À172.3 (2)
À177.94 (13)
Note: (a) data for compound (IV) are taken from Castillo et al. (2010).
ꢁ
´
o172 Lopez et al. C23H26ClN3O2, C22H23Cl2N3O and C26H31N3O2S2
Acta Cryst. (2010). C66, o168–o173

organic compounds
Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem.
Int. Ed. Engl. 34, 1555–1573.
Binot, G., Quiclet-Sire, B., Saleh, T. & Zard, S. Z. (2003). Synlett, pp. 382–
384.
Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De
Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38,
381–388.
(III), the reference molecule was selected to have the same config-
uration at atom N51 and the same orientation of the aryl ring (C11—
C16) as found in compound (IV) (Castillo et al., 2010). The atom-
labelling schemes for (I)–(III) are based on that employed in (IV).
For all compounds, data collection: COLLECT (Hooft, 1999); cell
refinement: DIRAX/LSQ (Duisenberg et al., 2000); data reduction:
EVALCCD (Duisenberg et al., 2003); program(s) used to solve
structure: SIR2004 (Burla et al., 2005); program(s) used to refine
structure: SHELXL97 (Sheldrick, 2008); molecular graphics:
PLATON (Spek, 2009); software used to prepare material for
publication: SHELXL97 and PLATON.
´
Castillo, J. C., Abonıa, R., Hursthouse, M. B., Cobo, J. & Glidewell, C. (2010).
Acta Cryst. C66, o64–o66.
Duisenberg, A. J. M., Hooft, R. W. W., Schreurs, A. M. M. & Kroon, J. (2000).
J. Appl. Cryst. 33, 893–898.
Duisenberg, A. J. M., Kroon-Batenburg, L. M. J. & Schreurs, A. M. M. (2003).
J. Appl. Cryst. 36, 220–229.
Elguero, J. (1984). Pyrazoles and Their Benzo Derivatives, Vol. 5,
Comprehensive Heterocyclic Chemistry, edited by A. R. Katritzky & C. W.
Rees, pp. 167–303. Oxford: Pergamon.
Elguero, J. (1996). Pyrazoles, Vol. 2, Comprehensive Heterocyclic Chemistry,
edited by A. R. Katritzky, C. W. Rees & E. F. Scriven, pp. 1–75. Oxford:
Pergamon.
´
´
The authors thank ‘Servicios Tecnicos de Investigacion of
Universidad de Jaen’ and the staff for data collection. GL,
´
LMJand JQ thank COLCIENCIAS and Universidad del Valle
´
for financial support. JC thanks the Consejerıa de Innovacion,
Ciencia y Empresa (Junta de Andalucıa, Spain), the Univer-
´
sidad de Jaen (project reference UJA_07_16_33) for financial
support.
´
Ferguson, G., Glidewell, C., Gregson, R. M. & Meehan, P. R. (1998a). Acta
Cryst. B54, 129–138.
Ferguson, G., Glidewell, C., Gregson, R. M. & Meehan, P. R. (1998b). Acta
Cryst. B54, 139–150.
Gregson, R. M., Glidewell, C., Ferguson, G. & Lough, A. J. (2000). Acta Cryst.
B56, 39–57.
Hooft, R. W. W. (1999). COLLECT. Nonius BV, Delft, The Netherlands.
´
Supplementary data for this paper are available from the IUCr electronic
archives (Reference: SK3367). Services for accessing these data are
described at the back of the journal.
´
Ibarra-Rivera, T. R., Gamez-Montan˜o, R. & Miranda, L. D. (2007). Chem.
Commun. pp. 3485–3487.
Riddell, F. & Rogerson, M. (1996). J. Chem. Soc. Perkin Trans. 2, pp. 493–504.
Riddell, F. & Rogerson, M. (1997). J. Chem. Soc. Perkin Trans. 2, pp. 249–255.
¨
Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Gottingen,
Germany.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.
Spek, A. L. (2009). Acta Cryst. D65, 148–155.
References
´
Bacque, E., El Qacemi, M. & Zard, S. Z. (2004). Org. Lett. 6, 3671–3675.
ꢁ
´
Acta Cryst. (2010). C66, o168–o173
Lopez et al.
C23H26ClN3O2, C22H23Cl2N3O and C26H31N3O2S2 o173