Synthesis and structural assignment of oxanilo-N-arylhydrazonoyl chlorides

Article abstract of DOI:10.1002/1099-0690(200205)2002:10<1654::AID-EJOC1654>3.0.CO;2-U

Oxanilo-N-arylhydrazonoyl chlorides have been prepared from appropriate N-aryl-2-chloro-3-oxobutanamides by the Japp-Klingemann reaction. The structures of the title compounds have been established in the solid state by single-crystal X-ray structure determination and IR spectroscopy, and in solution by IR, UV, and ¹H and ¹³C NMR spectroscopy. The results indicate that the hydrazonoyl chloride moiety adopts the (Z)-configured form. In the crystal, intramolecular hydrogen bonds generally exist between the chloride function and the hydrazone hydrogen atom, and also between the amide hydrogen atom and the double-bonded nitrogen atom of the hydrazone moiety. In solution, this intramolecular hydrogen bonding could not be detected. In compounds with an ortho-chloro-substituted NH-aryl moiety, however, the chlorine atom is involved in hydrogen bonding to the NH hydrogen atom both in the crystal and in solution. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.

Full text of DOI:10.1002/1099-0690(200205)2002:10<1654::AID-EJOC1654>3.0.CO;2-U

FULL PAPER
Synthesis and Structural Assignment of Oxanilo-N-arylhydrazonoyl
Chlorides[‡]
Petra Frohberg,*[a] Guntram Drutkowski,[a] and Christoph Wagner[b]
Keywords: N-Arylhydrazonoyl chlorides / Synthetic methods
Oxanilo-N-arylhydrazonoyl chlorides have been prepared
from appropriate N-aryl-2-chloro-3-oxobutanamides by the
Japp−Klingemann reaction. The structures of the title com-
pounds have been established in the solid state by single-
tion and the hydrazone hydrogen atom, and also between
the amide hydrogen atom and the double-bonded nitrogen
atom of the hydrazone moiety. In solution, this intramolecular
hydrogen bonding could not be detected. In compounds with
crystal X-ray structure determination and IR spectroscopy, an ortho-chloro-substituted NH−aryl moiety, however, the
and in solution by IR, UV, and 1H and 13C NMR spectroscopy.
chlorine atom is involved in hydrogen bonding to the NH
The results indicate that the hydrazonoyl chloride moiety ad- hydrogen atom both in the crystal and in solution.
opts the (Z)-configured form. In the crystal, intramolecular
( Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany,
hydrogen bonds generally exist between the chloride func-
2002)
Introduction
particularly with respect to intra- and intermolecular hydro-
gen bonding, are to be found in the literature. Nevertheless,
The chemistry of N-arylhydrazonoyl halides has been the the structures of α-carbonyl-substituted N-arylhydrazonoyl
subject of much interest in recent years. This situation has halides are seldom discussed,[2,4,10] although investigation is
developed both from studies of the mechanism by which possible with the aid of NH signals of the CϭNNH group
they are formed but even more so from their use in organic as observed in NMR[2,4] and IR spectra.[2,10] In the context
synthesis. Various reviews concerning reactions of hy- of our studies on structure and hydrogen bonding, we now
drazonoyl halides have been published,[1] but only little at- report the synthesis and spectroscopic characterisation of
tention has yet been given to their structures. In molecules oxanilo-N-arylhydrazonoyl chlorides 1 and the establish-
containing the CϭNNH system, there is the possibility of ment of the molecular structures of these compounds both
distinct (E) and (Z) isomers. In comparison with phenylhy- in the solid phase and in solution. To investigate the struc-
drazones derived from α-dicarbonyl compounds, a further tural features, we were interested in variation of substituents
characteristic feature should include strong intra- and inter- R1 and R2. Furthermore, we also decided to synthesise ox-
molecular hydrogen-bonding interactions. The literature in- anilo-N-methyl-N-phenylhydrazonoyl chloride (2).
dicates that hydrazonoyl halides exist as (Z) isomers, con-
firmed both by spectroscopic studies[2Ϫ4] and by X-ray dif-
fraction analysis.[3b,5Ϫ7] It is known that (Z) isomers are
thermodynamically more stable[8] and that (E) and (Z) iso-
mers of different hydrazonoyl halides do not rapidly in-
terconvert under various conditions known to favour equi-
libration among simple imine isomers.[5,9] Exner et al.[10]
found that derivatives of benzoylcarbohydrazonoyl brom-
Results and Discussion
ides occurred as (E) isomers. Numerous works concerning
structural aspects of α-carbonyl-substituted arylhydrazones,
Synthesis
Two literature routes for the preparation of oxanilo-N-
[‡]
arylhydrazonoyl chlorides are known (see Scheme 1). By
the sequence outlined in Scheme 1, Path A, Lozinskij et
al.[11] obtained derivatives of 1 with a limited R2 substitu-
tion pattern. It was found that the intermediate oxalo-N-
monoarylhydrazonoyl chlorides 4 were only stable if the R2
aryl ring bore para or ortho substituents.[12] For our pur-
poses, we prepared title compounds 1 by the steps shown
Derivatives of Arylhydrazonic Acids, 1
[a]
Institute of Pharmaceutical Chemistry, Martin Luther
University Halle-Wittenberg
Wolfgang-Langenbeck-Straße 4, 06120 Halle, Germany,
Fax: (internat.) ϩ 49-(0)345/552-7027
E-mail: frohberg@pharmazie.uni-halle.de
Institute of Inorganic Chemistry, Martin Luther University
Halle-Wittenberg
[b]
Kurt-Mothes-Straße 2, 06120 Halle, Germany
1654
 WILEY-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002 1434Ϫ193X/02/0510Ϫ1654 $ 20.00ϩ.50/0 Eur. J. Org. Chem. 2002, 1654Ϫ1663

Oxanilo-N-arylhydrazonoyl Chlorides
FULL PAPER
Details of the synthesis of oxanilo-N-methyl-N-phenylhy-
drazonoyl chloride (2) were not available in the literature.
An attempt to methylate the corresponding N-phenylhy-
drazonoyl chloride, as described for aryl(phenyl)hydraz-
ines,[16] was unsuccessful. The applicability of the methods
for preparation of hydrazonoyl halides is limited. Halogena-
tion of hydrazones is accompanied by halogenation in the
N-aryl part of the hydrazone unless the aryl nucleus is deac-
tivated. Furthermore, the JappϪKlingemann reaction is un-
fortunately restricted to N-monoaryl-substituted hy-
drazones. We therefore had to chlorinate the appropriate
hydrazide, and the synthetic route we chose is outlined in
Scheme 3. Treatment of oxanilide chloride (7), prepared ac-
cording to ref.[17] with N-methyl-N-phenylhydrazine (8) was
carried out in toluene at room temperature, monitored by
TLC (see Exp. Sect). Oxanilo-N-methyl-N-phenylhydrazide
(9) was produced in 50% yield. The subsequent chlorination
was first attempted with thionyl chloride,[18] but no product
2 could be isolated. Treatment of 9 with phosphorus pen-
tachloride in toluene, however, effected the chlorination, af-
fording 2, which was purified by flash chromatography.
Scheme 1. Routes to oxamo-N-arylhydrazonoyl chlorides
Scheme 2. Synthesis of 2-chloro-3-oxobutanamides 6
in Scheme 1, Path B, allowing unlimited variation of R1 and
R2. The general route to 2-chloro-3-oxobutanamides 6 that
we used is shown in Scheme 2.
N-Aryl-3-oxobutanamides 5 can be prepared by two
main methods: i) the diketeneϪamine reaction[13] or ii) the
esterϪamine method.[14] We synthesised derivatives 5 by the
esterϪamine method; an optimised general procedure is
given in the Exp. Sect. The crude products were chlorinated
with sulfuryl chloride in toluene to provide 2-chloro-3-
oxobutanamides 6a؊e as white crystals.
Scheme 3. Synthesis of oxanilo-N-methyl-N-phenylhydrazonoyl
chloride (2)
Structural Assignment ؊ Solid Phase
Crystal Structure
The title compounds were prepared by JappϪ
Klingemann cleavage of butanamides 6 with diazotised an-
ilines according to known procedures.[15] The substitution
patterns of 1 are summarised in Table 1.
Searches in the database of the Cambridge Crystallo-
graphic Data Centre and conventional literature searches
revealed that crystal structures of arylhydrazonoyl halides
have been reported only in a very few cases. The structures
of two compounds with a carbonyl group (nitrile)[6] or a
corresponding structure (PϭO)[3a] in the position α to the
hydrazone function have been obtained by X-ray diffraction
analysis. In contrast, the crystal structures of a large num-
ber of phenylhydrazones have been determined, and several
structural features have emerged.[19] In virtually all in-
stances, the hydrazone molecule adopts a planar conforma-
tion. When aromatic substituents or functional groups cap-
able of conjugation with the CϭN bond are present, the
CϪN portion of the hydrazone linkage becomes
lengthened, and this is accompanied by a commensurate
decrease in the NϪN bond length.
Table 1. Substitution patterns of R1NHCOC(Cl)ϭNNHR2 (1)
R1
R2
R1
R2
1a Ph
1b Ph
3-F3C-C6H4 1g 2-Cl-C6H4 2-NC-C6H4
2-F-C6H4 1h 3-Cl-C6H4 Ph
1c 3-F3C-C6H4 Ph
1i
1j
3-Cl-C6H4 2-Cl-C6H4
3-Cl-C6H4 3-Cl-C6H4
1d 2-Cl-C6H4
1e 2-Cl-C6H4
1f 2-Cl-C6H4
Ph
2-Cl-C6H4
3-Cl-C6H4
1k 3-Cl-C6H4 1-naphthyl
1l 4-Cl-C6H4 3-Cl-C6H4
Eur. J. Org. Chem. 2002, 1654Ϫ1663
1655

P. Frohberg, G. Drutkowski, C. Wagner
FULL PAPER
˚
We determined the molecular structures of the derivatives
1d and 1k by X-ray diffraction analysis; the molecular
structures and atom-numbering schemes are shown in Fig-
ures 1 and 2, respectively. The hydrazonoyl chloride moiety
is (Z)-configured in both structures. In addition, the two
aryl moieties (aryl amide and aryl hydrazone) are essentially
coplanar. Least-squares calculations showed that these moi-
eties are twisted with respect to each other by angles of 3°
in molecule A and 7° in molecule B of 1d, and 9° in the
structure of 1k (see Table 2). The key bond lengths in 1d
and 1k are listed in Table 3. The N(1)ϪN(2) bond lengths
Table 2. Deviations [A] of the atoms of the hydrazone structure
from the calculated least-squares planes through atoms
C(9)ϪC(14) (phenyl ring of 1d) or C(9)ϪC(18) (naphthyl ring of
1k)
1d
1k
Molecule A
Molecule B
N(1)
N(2)
C(1)
C(2)
O
0.004(5)
Ϫ0.023(5)
0.031(7)
0.005(9)
Ϫ0.017(10)
0.008(4)
0.005(5)
0.030(7)
Ϫ0.007(8)
Ϫ0.217(10)
Ϫ0.028(2)
0.146(3)
0.011(3)
0.184(4)
Ϫ0.201(4)
˚
(1.33 A) in both structures are consistent with the values
˚
found in the structures of pyridazine rings (1.35 A), but not
[20]
˚
of hydrazines (1.45 A).
Both the C(1)ϪN(2) distances
and the C(1)ϪCl(1) bond lengths are well within the ranges
typically occurring in other hydrazonoyl chlorides
˚
Table 3. Characteristic bond lengths [A] in the molecule structures
of 1d and 1k
˚
˚
(1.26Ϫ1.29
A
for CϪN and 1.70Ϫ1.76
A
for
CϪCl).[3a,7,21,22] The structures of the molecules in the crys-
tals of 1d and 1k, with intra- and intermolecular hydrogen
bonding, are outlined in Figures 3 and 4.
1d
1k
Molecule A
Molecule B
C(9)ϪN(1)
N(1)ϪN(2)
C(1)ϪN(2)
C(1)ϪC(2)
C(1)ϪCl(1)
1.401(4)
1.333(3)
1.268(3)
1.490(4)
1.732(3)
1.396(3)
1.329(3)
1.271(3)
1.482(4)
1.729(3)
1.404(2)
1.329(2)
1.268(2)
1.491(2)
1.736(2)
Figure 1. Molecular structure and atom-numbering scheme of one
of the two independent molecules of 1d (displacement ellipsoids
with 50% probability)
Figure 3. Structures of two independent molecules in the crystal of
compound 1d, showing intra- and intermolecular hydrogen bond-
ing (dashed lines)
Figure 2. Molecular structure of 1k with atom-numbering scheme
(displacement ellipsoids with 50% probability)
Two intramolecular hydrogen bonds N(1)ϪH(1)···Cl(1)
and N(3)ϪH(2)···N(2) are present in both compounds (see
Table 4). The formation of such an intramolecular
NϪH···Cl hydrogen bond in hydrazonoyl chlorides has also
been described by CherepinskiϪMalow[7] and Buzykin.[3]
Figure 4. Structure of two molecules in the crystal of compound
1k, showing intra- and intermolecular hydrogen bonding (dashed
lines)
1656
Eur. J. Org. Chem. 2002, 1654Ϫ1663

Oxanilo-N-arylhydrazonoyl Chlorides
FULL PAPER
˚
tances and 2.64 A (10 and 11a) for the Cl···H distances. In
Table 4. Potential intra- and intermolecular hydrogen bonds; dis-
tances (DϪH, H···A, D···A) are given in A, angles (DϪH···A) in °
˚
˚
our structures, distances of 2.93Ϫ2.94 A for Cl(1)···N(1)
and of 2.53Ϫ2.58 A for Cl(1)···H(1) are found.
˚
Type, DonorϪH···Acceptor DϪH H···A D···A
Intra N(1)ϪH(1)···Cl(1)
DϪH···A
An additional intramolecular hydrogen bond is formed
in the structure of 1d between the anilide H atom and the
o-chloro substituent of the anilide moiety. However, the na-
ture of intermolecular hydrogen bonding is different (see
Table 4). In the crystal of 1d, two unequal intermolecular
hydrogen bonds are formed between the hydrazone H atom
and the carbonyl oxygen atom (see Figure 3). In compound
1k, one intermolecular bond occurs between the anilide hy-
drogen atom and the oxygen atom of a neighbouring molec-
ule (see Figure 4).
1d, molecule A
1d, molecule B
1k
0.87(3) 2.57(3) 2.93(3) 106(3)
0.88(3) 2.53(3) 2.937(3) 109(3)
0.86(2) 2.54(2) 2.926(2) 108(2)
Intra N(3)ϪH(2)···N(2)
1d, molecule A
1d, molecule B
1k
0.78(3) 2.23(3) 2.659(4) 115(3)
0.81(3) 2.23(3) 2.674(4) 115(3)
0.83(3) 2.29(2) 2.688(2) 109(2)
Intra N(3)ϪH(2)···Cl(2)
1d, molecule A
1d, molecule B
Inter N(1)ϪH(1)···O
1d, molecule A
1d, molecule B
Inter N(3)ϪH(2)···O
1k
0.78(3) 2.50(3) 2.938(3) 117(3)
0.81(3) 2.54(3) 2.95(3) 113(2)
0.87(3) 2.59(3) 3.371(4) 150(3)
0.88(3) 2.29(3) 3.141(4) 162(3)
IR Spectroscopy
Derivatives of structure 1 with R1 ϭ Ph were described
previously by Shawali et al.[15b,15c] However, no attempts
were undertaken either to assign the observed NH bands in
the IR spectra or to study the configurations and conforma-
tions of these anilides. Related compounds with ester and
ketone structures as well in the position α to the hydrazone
moiety were assumed to exist in the (Z) configuration.[2]
The authors explained the likelihood of the (Z) form in
terms of the absence of strong intramolecular hydrogen
bonds, which should exist in the (E)-configured structure
0.83(3) 2.18(3) 2.918(2) 148(2)
In the related compounds 10, 11a, and 11b, these workers (see Scheme 4). Such an associated NH group would cause
measured 2.96 A (10) and 2.87 A (11a,b) for the Cl···N dis- a red shift of the NH stretching band to 3080 cmϪ1 [23]
.
˚
˚
Table 5. Characteristic spectroscopic data of hydrazonoyl chlorides 1 and 2
R1
R2
IR (KBr)
IR (CDCl3)[a] 1H-NMR (CDCl3) 1H-NMR ([D6]DMSO) 13C-NMR ([D6]DMSO)
ν [cmϪ1
δ values δ values δ values
CϭO NH CϭO CONH NNH CϭN
UV
ν [cmϪ1
]
]
λmax [nm] (log ε)
Band C
NH
NNH
8.30
8.37
8.24
8.24
8.73
8.24
8.73
8.22
8.71
8.21
8.76
8.21
Ϫ
CONH
10.20
10.14
10.32
9.74
CϭO
156.9
157.0
157.8
157.2
157.1
157.2
156.9
158.0
156.9
157.8
157.9
157.4
158.5
1a Ph
1b Ph
3-F3C-C6H4 3384, 3240 1667 3405, 1683 8.46
3327
2-F-C6H4
10.54
9.41
119.8
121.5
117.8
117.4
121.8
118.9
121.2
118.2
122.3
119.7
120.9
119.5
117.7
330 (4.40)
327 (4.35)
336 (4.41)
342 (4.38)
331 (4.32)
339 (4.42)
338 (4.29)
337 (4.44)
330 (4.41)
333 (4.45)
350 (4.32)
334 (4.47)
331 (4.25)
3324 br.
1658 3400, 1680 8.52
3335
1c 3-F3C-C6H4 Ph
1d 2-Cl-C6H4 Ph
3375, 3231 1667 3400, 1684 8.60
3325
3356, 3291, 1672 3368, 1681 9.35
10.38
10.48
9.01
3235
3321
1e 2-Cl-C6H4 2-Cl-C6H4 3371, 3320 1693 3370, 1684 9.36
10.00
9.89
3317
1f 2-Cl-C6H4 3-Cl-C6H4 3348, 3275 1680 3368, 1688 9.38
10.61
10.62
10.35
8.89
3322
1g 2-Cl-C6H4 2-NC-C6H4 3354, 3208 1687 3381, 1693 9.32
3316
9.57
1h 3-Cl-C6H4 Ph
3379, 3281, 1663 3401, 1687 8.49
3236 3327
10.16
10.33
10.28
10.31
10.26
10.05
1i 3-Cl-C6H4 2-Cl-C6H4 3313, 3272 1651 3405, 1688 8.45
3324
1j 3-Cl-C6H4 3-Cl-C 6H4 3375, 3247 1668 3400, 1681 8.46
3320
10.49
10.00
10.46
Ϫ
1k 3-Cl-C6H4 1-naphthyl 3300 br.
1653 3393, 1680 8.58
3338
1l 4-Cl-C6H4 3-Cl-C6H4 3370, 3246 1669 3402, 1685 8.48
3324
2[b] Ph
Ph
3315
1651 3388 1681 8.63
[a]
[b]
Concentration 0.03 , cell thickness 0.5 mm. N1 ϭ methyl- and phenyl-substituted.
Eur. J. Org. Chem. 2002, 1654Ϫ1663
1657

P. Frohberg, G. Drutkowski, C. Wagner
FULL PAPER
in the general NNH···ClϪCϭN and CONH···NϭC bond-
ing. The red shift of the NNH stretching band in the spec-
trum of 1g could be explained with a hydrogen strongly
associated atom to the o-CN group of the phenyl substitu-
ent.
In summary of the X-ray and IR spectroscopic results for
solid samples, we were able to conclude that all compounds
except 1e formed an intramolecular hydrogen bond between
the anilide hydrogen atom and the double-bonded nitrogen
atom of the hydrazone moiety. In four compounds (1b, 1i,
1k, and 2), an additional intermolecular bond between the
mentioned anilide hydrogen atom and the carbonyl func-
tion of a neighbouring molecule is assumed. In contrast to
the anilide, the hydrazone hydrogen atom is probably
doubly associated in nearly all substances, intramolecularly
to the Cl atom of the hydrazonoyl chloride structure and
intermolecularly to the carbonyl oxygen atom of a neigh-
bouring molecule. The differently associated NNH···OϭC
moieties, as observed in the structure of 1d, could be differ-
entiated in the IR spectra. The results indicate that intramo-
lecular association does not exist between the hydrazone
hydrogen atom and the carbonyl oxygen atom and, accord-
ingly, that all compounds are (Z)-configured.
Scheme 4. Isomeric forms of α-carbonyl-substituted hydrazonoyl
chlorides
In the phenylhydrazone of dimethyl 2-oxopropanedioate,
other authors found a band near 3150 cmϪ1 for intramolec-
ular association of the NH moiety to the carbonyl func-
tion.[24] Prasad et al. observed NH stretching bands be-
tween 3240 and 3280 cmϪ1 and ruled out the (E) configura-
tion.[2] Additionally, Buzykin et al. described NH stretching
bands for benzenecarbohydrazonoyl chlorides 11 between
3290 and 3315 cmϪ1 [3b]
Characteristic infrared absorption
.
bands of hydrazonoyl chlorides 1 and 2 in KBr are given
in Table 5.
For comparison, some of the samples were also prepared
in nujol, but only very small differences were found. In all
cases, medium to strong bands due to NH stretching were
observed in the 3400Ϫ3200 cmϪ1 region. Furthermore, the
spectra showed strong bands for CϭO stretching
(1690Ϫ1670 cmϪ1), aromatic CϭC stretching (near 1600
cmϪ1) and CϭN stretching (1560Ϫ1570 cmϪ1).
Structural Assignment ؊ in Solution
All crystal structures of arylhydrazones with an α-anilide
moiety, such as that in chlorides 1d and 1k and related ami-
drazones,[25] demonstrate intramolecular association be-
tween the anilide hydrogen atom and the double-bonded
hydrazone nitrogen atom. There is no evidence for a free
CONH moiety in the solid phase. In addition, it has been
found that the hydrazone NH group in hydrazonoyl chlor-
ides displays an absorption band in the range of 3150 cmϪ1
IR Spectroscopy
Key IR spectroscopic data of 1 and 2 in CDCl3 solution
are listed in Table 5. Most of the samples were insoluble in
cyclohexane and benzene, and so we chose deuteriochloro-
form as solvent, with the advantage of being able to use the
same solution for NMR and IR experiments. We expected
that interaction with chloroform as solvent should not in-
fluence intramolecular associations. On changing from the
solid state to the CDCl3 solution, the bands for both NH
atoms were shifted to a greater or lesser extent to higher
wavenumbers, indicating that intermolecular hydrogen
bonds were abolished. However, the region for the anilide
hydrogen atom intramolecularly associated to the CϭN ni-
trogen atom in solid samples was displaced as well. It hence
followed that the NH stretching band at around 4000 cmϪ1
was attributable to the free anilide NH group without any
association, confirmed by the solvent and concentration de-
pendence of this band.
to at most 3340 cmϪ1 [2,3,10,21,26]
We observed three regions
.
for the CONH moiety, one main and two additional regions
of NNH stretching. With the aid of the results of the crystal
structure analyses of 1d and 1k, together with literature
data, the assignment of NNH stretching was performed
(see Table 6).
However, exceptions are noted in the spectra of ortho-
substituted derivatives 1e and 1g. We assume that both NH
hydrogen atoms in 1e are involved in hydrogen bonding to
the corresponding o-Cl atoms of the aryl moieties but not
Literature data indicate that the free hydrazone hydrogen
Table 6. Regions of NH stretching bands in the IR spectra of hy-
drazonoyl chlorides 1 and 2 in KBr
band appears at 3335Ϫ3342 cm .
Ϫ1 [3b,10,22,27] In the IR spec-
tra of chlorides 1b and 1k, recorded in CDCl3, this band
was found. All the other IR spectra exhibited a band
slightly shifted to lower wavenumber by about 10 cmϪ1. In-
teractions of the hydrazone hydrogen atom with the solvent
(NH···Cl) were probably observed, although these were not
present in 1b and 1k because of steric effects. In addition,
small differences of about 3Ϫ4 cmϪ1 occurred with chan-
ging concentration (from 0.15 to 0.015  in CDCl3). No
substantial dependence on the nature of substituents on the
aromatic moiety was found [∆ν(NH) ϭ Ϯ5 cmϪ1]. As
ν [cmϪ1] for
CONH··· associated to
···NϭC (intra)
···NϭC (intra) and ···o-Cl (intra)
···NϭC (intra) and ···OϭC (inter)
NNH···associated to
···o-Cl/F (intra)
···Cl-CϭN (intra) and ···OϭC (inter, weak)
···Cl-CϭN (intra) and ···OϭC (inter, strong)
3370Ϫ3390
3340Ϫ3360
3300Ϫ3330
3310Ϫ3325
3270Ϫ3290
3220Ϫ3250
1658
Eur. J. Org. Chem. 2002, 1654Ϫ1663

Oxanilo-N-arylhydrazonoyl Chlorides
FULL PAPER
known for anilides, the electrons are delocalised and sub-
stituent effects are evened out.[3b]
NMR Spectroscopy
In general, variations in the intensity and position of
ν(NH) stretching frequencies correlated with chemical shift
[δ(NH)] variations, but qualitative differentiation and the
degree of hydrogen bonding involved has been based prin-
cipally on the latter. As discussed previously, δ(NH) values
have proved to be an extremely sensitive monitor of hydro-
gen bonding in phenylhydrazone derivatives.[26] 1H and 13C
NMR spectroscopic data for 1 and 2 are listed in Table 5.
The chemical shift of NNH protons of hydrazonoyl halides
are found in the regions of δ ϭ 8Ϫ9 in CDCl3 and 10Ϫ11
in [D6]DMSO.[3a,4,7,10] In contrast, the value of δ(NH) in
phenylhydrazones that form intramolecular hydrogen bonds
to carbonyl oxygen atoms is reported to be in the range of
δ ϭ 13Ϫ15, independent of the solvent.[28Ϫ30] Comparison
of 1H NMR signals of NH in CDCl3 and [D6]DMSO indic-
ated that most of them were dependent on the solvent, as
is demonstrated in Figure 5.
Figure 6. Solvent dependence of the chemical shifts (δ) of the anil-
ide (CONH, open symbols) and the hydrazone (NNH, closed sym-
bols) protons
1
detected in the H NMR spectra. However, these interac-
tions were weak, and caused only small differences in the
chemical shift of the NH signal. For instance, on changing
the concentration of the naphthyl-substituted hydrazonoyl
chloride 1k from 5% to 0.5%, the NNH proton signal was
shifted by about 0.07 ppm.
The appearance of intramolecular hydrogen bonds, as
observed in the crystal structures (CϭO···HN and
Cl···HN), could not be investigated in all cases because of
the limited solubility of nearly all the compounds in nonpo-
lar benzene.
In the 13C NMR spectra, it is worth mentioning that the
signals of the hydrazone C atoms in 13C NMR spectra were
shifted by about 2Ϫ3 ppm in the spectra of 1b, 1e, 1g, 1i,
and 1k. The signals appeared near δ ϭ 121Ϫ122. This effect
is attributable to the ortho substitution of the hydrazone
1
moiety and is in accordance with H NMR spectroscopic
results.
Except for the intramolecular hydrogen bond between
anilide or hydrazone hydrogen atom and corresponding
ortho substituents of the aryl moiety (see Figure 6), there
was no evidence of the existence of other intramolecular
associations in any of the experiments.
Figure 5. Solvent dependence of the chemical shifts (δ) of the
anilide (CONH, open symbols) and the hydrazone (NNH, closed
symbols) protons
However, it was immediately obvious that the chemical
shifts of some of the signals showed small differences, espe-
cially in the less polar solvents benzene or deuteriochloro-
form, or were largely unchanged. In accordance with the IR
UV Spectroscopy
The UV absorption spectra of compounds 1 and 2, sim-
spectroscopic results, it was found that these NH moieties ilarly to those of typical phenylhydrazones, showed three
formed intramolecular hydrogen bonds to o-Cl atoms in hy- very intense (εmax Ͼ 1000) absorption bands with their
drazonoyl chlorides 1d؊1g and 1i (see Figure 6). The chem- maxima situated at approx. 250 nm (band A), in the range
ical shift of the NNH proton of the ortho-fluoro-substituted of 280Ϫ300 nm (band B) and 330Ϫ340 nm (band C). Key
derivative 1b was weakly dependent on the solvent, but even UV spectroscopic data are summarised in Table 5.
less so than the δ(NH) values of compounds without an
Small differences were found in the intensity of the band
ortho substituent. The unchanged chemical shift of the with the largest wavelength (band C), which indicates the
NNH proton in the spectrum of naphthylhydrazonoyl degree of electron delocalisation. In the spectra of derivat-
chloride 1k could be explained by a steric effect of the ives 1e, 1g, 1k, and 2, the band had a slightly lower intensity
naphthyl substituent. In accordance, this proton behaves in than those in the other spectra. This could point to a devi-
the essentially nonpolar solvents benzene and chloroform ation in the planarity of the CϭNNH fragment, as ob-
like a NH moiety associated with an o-Cl atom, as does the served by Buzykin.[3b] The X-ray data of 1k support this
NNH group in the o-cyanophenylhydrazonoyl chloride 1g assumption; deviations of this fragment from planarity are
(see Figure 6).
larger than those in the structure of 1d. It may be specu-
Interactions between the hydrazone hydrogen atom and lated that, in solution, the molecules adopt another con-
deuteriochloroform, observed in the IR spectra, were also formation that is energetically favourable. In hydrazonoyl
Eur. J. Org. Chem. 2002, 1654Ϫ1663
1659

P. Frohberg, G. Drutkowski, C. Wagner
FULL PAPER
ucts were used without further purification. The obtained crude
products were: 3-oxo-N-[3-(trifluoromethyl)phenyl]butanamide
(5b), N-(2-chlorophenyl)-3-oxobutanamide (5c), N-(3-chloro-
phenyl)-3-oxobutanamide (5d), and N-(4-chlorophenyl)-3-oxobut-
anamide (5e).
chloride 2, the influence of alkyl substitution of hydrazone
N1 is evident. The resonating system is diminished, which
correlates with the decreased absorption intensity. A cor-
relation has been found between the electronic properties of
substituents on the arylhydrazone moiety and UV λmax for
compounds that have proved to form strong intramolecular
hydrogen bonds, such as CϭNNH···OϭC.[31] Only small
differences in the range of 320Ϫ340 nm were observed in
the λmax values of hydrazonoyl chlorides 1, which would
preclude such a correlation. The high value of λmax of 1k
indicates a large system of electron delocalisation over the
naphthyl ring.
General Procedure for the Preparation of N-Aryl-2-chloro-3-oxobut-
anamides 6 (GP 2): The synthesis was based on ref.[32] Sulfuryl
chloride (1.5 g, 11 mmol) was added dropwise to the stirred suspen-
sion of the appropriate N-aryl-3-oxobutanamide (10 mmol, in
15 mL of dried toluene) if necessary with ice cooling. The reaction
was monitored by TLC. If required, the mixture was warmed to
complete the reaction. The solid product was filtered off, dried and
recrystallised. If the product did not crystallise, the toluene was
evaporated and the residue was recrystallised from the given solv-
ent. In accordance with literature data, the following compounds
were obtained: 2-chloro-3-oxo-N-phenylbutanamide (6a),[32a] 2-
chloro-3-oxo-N-[3-(trifluoromethyl)phenyl]butanamide (6b) (m.p.
65Ϫ67 °C; ref.[33] 61Ϫ63 °C), 2-chloro-N-(2-chlorophenyl)-3-
oxobutanamide (6c),[34] 2-chloro-N-(3-chlorophenyl)-3-oxobutana-
Conclusion
In summary of all the spectroscopic data, it could be con-
cluded that the hydrazonoyl chlorides 1 and 2 exist in the
(Z)-configured form in the solid state as well as in solution.
The observed CO···NH and NNH···Cl intramolecular hy-
drogen bonds in the crystal structure could not be detected
in solution. It is evident that the independence of ν(NH)
and δ(NH) in the spectra of ortho-substituted NHϪaryl
moieties reflects intramolecular hydrogen bonding of the
appropriate NH group to the ortho substituent in the phenyl
ring. In contrast to the findings of Exner et al.,[10] who as-
sumed an intramolecular association NNH···OϭC in sub-
stituted benzoylcarbohydrazonoyl bromides, there was no
evidence of such association in the molecules of the com-
pounds under discussion.
mide
(6d),[34]
2-chloro-N-(4-chlorophenyl)-3-oxobutanamide
(6e).[34]
General Procedure for the Preparation of Arylhydrazonoyl Chlorides
1 (GP 3):[15] The appropriate arylamine (0.01 mol) was dissolved
in 24 mL of half-concentrated HCl and diazotised with a solution
of sodium nitrite (0.01 mol, 0.69 g) in 3 mL of water at 0Ϫ5 °C.
The freshly prepared solution of the diazotised aniline was added
dropwise to a cooled mixture of sodium acetate (4.0 g) and N-aryl-
2-chloro-3-oxobutanamide 6 (0.01 mol) in 50 mL of methanol at
5Ϫ10 °C. After the mixture was stirred for 2 h, the solid was filtered
off, washed with water, dried, and recrystallised from the given
solvent.
(1Z)-2-Anilino-2-oxo-N-[3-(trifluoromethyl)phenyl]ethane-
hydrazonoyl Chloride (1a): This compound was prepared from 3-
trifluoromethylaniline (0.01 mol, 1.6 g) and 2-chloro-3-oxo-N-
phenylbutanamide (0.01 mol, 2.1 g). Yield: 2.3 g (68%) of pale yel-
low needles from heptane/acetone, m.p. 206Ϫ208 °C. 1H NMR
([D6]DMSO): see Table 5; additional signals: δ ϭ 7.11Ϫ7.90 (9 H,
arom. H). 13C NMR ([D6]DMSO): see Table 5; additional signals:
δ ϭ 111.1Ϫ143.6 (13 C, arom. C and CF3). MS (70 eV): m/z (%) ϭ
341 (45) [Mϩ], 305 (40), 93 (100). C15H11ClF3N3O (341.72): calcd.
C 52.72, H 3.24, Cl 10.37, F 16.68, N 12.30; found C 52.57, H
3.31, Cl 10.39, F 16.49, N 12.33.
Experimental Section
General: Melting points were determined with a Kofler hot-stage
apparatus. IR spectra were recorded with a Specord 75 IR (Carl
Zeiss Jena). UV spectra were determined with an HP8452A diode
array spectrophotometer and were recorded in ethanol; mass spec-
tra with an AMD 402 from AMD INTEDRA (70 eV); the NMR
spectra were recorded with a Gemini 2000 and a Gemini 200, oper-
ating at 399.96 and 199.95 MHz for 1H NMR and at 100.6 and
50.3 MHz for 13C NMR spectra. TMS was used as internal stand-
ard. Chemical shifts are given in δ units and refer to the centre of
the signal (s ϭ singlet, d ϭ doublet, t ϭ triplet, m ϭ multiplet). N-
Phenyl-3-oxobutanamide (5a) was purchased from Aldrich.
(1Z)-2-Anilino-N-(2-fluorophenyl)-2-oxoethanehydrazonoyl Chloride
(1b): This compound was prepared from 2-fluoroaniline (0.01 mol,
1.1 g) and 2-chloro-3-oxo-N-phenylbutanamide (0.01 mol, 2.1 g).
Yield: 2.5 g (87%) of pale yellow needles from chloroform/heptane,
1
m.p. 130Ϫ134 °C. H NMR ([D6]DMSO): see Table 5; additional
signals: δ ϭ 7.02Ϫ7.92 (9 H, arom. H). 13C NMR ([D6]DMSO):
see Table 5; additional signals: δ ϭ 115.6Ϫ138.2 (11 C, arom. C),
149.8, 152.2 (d, 1 C, arom. CF). MS (70 eV): m/z (%) ϭ 291 (100)
[Mϩ], 255 (73), 110 (50), 93 (100), 83 (50). C14H11ClFN3O (291.72):
calcd. C 57.65, H 3.80, Cl 12.15, F 6.51, N 14.40; found C 57.26,
H 3.67, Cl 12.16, F 6.41, N 14.44.
General Procedure for the Preparation of N-Aryl-3-oxobutanamides
5 (Ester؊Amine Method, GP 1): In a three-necked distillation flask
of a distillation apparatus, ethyl acetoacetate (1.5 mol, 190 mL) was
heated to 150Ϫ160 °C. Freshly distilled or recrystallised arylamine
(0.3 mol, solid arylamines were dissolved in a small amount of
(1Z)-2-Oxo-N-phenyl-2-{[3-(trifluoromethyl)phenyl]amino}ethane-
dry dimethylformamide) was added with stirring over 30 min. The hydrazonoyl Chloride (1c): This compound was prepared from anil-
temperature of the solution was kept between 150 and 160 °C until
no more ethanol or ethanol/ester azeotrope distilled. The mixture
was cooled to 80 °C and most of the excess ethyl acetoacetate was
distilled under reduced pressure. The residue was transferred to a
porcelain dish for crystallisation. After 12 h, the solid was pulv-
erised and washed with ice-cooled ether. The colourless crude prod-
ine (0.01 mol, 0.93 g) and 2-chloro-3-oxo-N-[3-(trifluoromethyl)-
phenyl]butanamide (0.01 mol, 2.8 g). Yield: 2.2 g (66%) of pale yel-
low solid from heptane/acetone, m.p. 200Ϫ204 °C. 1H NMR
([D6]DMSO): see Table 5; additional signals: δ ϭ 6.96Ϫ8.18 (9 H,
arom. H). 13C NMR ([D6]DMSO): see Table 5; additional signals:
δ ϭ 115.0Ϫ142.9 (13 C, arom. C and CF3). MS (70 eV): m/z (%) ϭ
1660
Eur. J. Org. Chem. 2002, 1654Ϫ1663

Oxanilo-N-arylhydrazonoyl Chlorides
FULL PAPER
341 (100) [Mϩ], 161 (48), 92 (53) 65 (40). C15H11ClF3N3O (341.72):
calcd. C 52.72, H 3.24, Cl 10.37, F 16.68, N 12.30; found C 52.54,
H 3.31, Cl 10.36, F 16.51, N 12.30.
(1Z)-N-(2-Chlorophenyl)-2-[(3-chlorophenyl)amino]-2-oxoethane-
hydrazonoyl Chloride (1i): This compound was prepared from 2-
chloroaniline (0.01 mol, 1.3 g) and 2-chloro-N-(3-chlorophenyl)-3-
oxobutanamide (0.01 mol, 2.5 g). Yield: 1.7 g (50%) of flat, plate-
like, light yellow crystals from chloroform/acetone, m.p. 184Ϫ188
°C. 1H NMR ([D6]DMSO): see Table 5; additional signals: δ ϭ
7.04Ϫ7.99 (8 H, arom. H). 13C NMR ([D6]DMSO): see Table 5;
additional signals: δ ϭ 117.2Ϫ139.7 (12 C, arom. C). MS (70 eV):
m/z (%) ϭ 341 (65) [Mϩ], 127 (100), 99 (45). C14H10Cl3N3O
(342.62): calcd. C 49.08, H 2.94, Cl 31.04, N 12.26; found C 49.01,
H 2.99, Cl 30.92, N 12.20.
(1Z)-2-[(2-Chlorophenyl)amino]-2-oxo-N-phenylethanehydrazonoyl
Chloride (1d): This compound was prepared from aniline (0.01 mol,
0.93 g) and 2-chloro-N-(2-chlorophenyl)-3-oxobutanamide (0.01
mol, 2.5 g). Yield: 1.6 g (51%) of yellow crystals from chloroform/
heptane, m.p. 200Ϫ203 °C. 1H NMR ([D6]DMSO): see Table 5;
additional signals: δ ϭ 6.96Ϫ7.91 (9 H, arom. H). 13C NMR
([D6]DMSO): see Table 5; additional signals: δ ϭ 114.9Ϫ137.7
(12 C, arom. C). MS (70 eV): m/z (%) ϭ 307 (65) [Mϩ], 127 (100),
91 (45). C14H11Cl2N3O (308.17): calcd. C 54.57, H 3.60, Cl 23.01,
N 13.63; found C 54.51, H 3.62, Cl 23.00, N 13.62.
(1Z)-N-(3-Chlorophenyl)-2-[(3-chlorophenyl)amino]-2-oxoethane-
hydrazonoyl Chloride (1j): This compound was prepared from 3-
chloroaniline (0.01 mol, 1.3 g) and 2-chloro-N-(3-chlorophenyl)-3-
oxobutanamide (0.01 mol, 2.5 g). Yield: 2.4 g (72%) of a yellow-
orange, amorphous solid from chloroform, m.p. 143Ϫ145 °C. 1H
NMR ([D6]DMSO): see Table 5; additional signals: δ ϭ 6.97Ϫ7.88
(8 H, arom. H). 13C NMR ([D6]DMSO): see Table 5; additional
signals: δ ϭ 113.5Ϫ144.3 (12 C, arom. C). MS (70 eV): m/z (%) ϭ
341 (65) [Mϩ], 127 (100), 99 (45). C14H10Cl3N3O (342.62): calcd.
C 49.08, H 2.94, Cl 31.04, N 12.26; found C 48.75, H 3.03, Cl
31.03, N 12.29.
(1Z)-N-(2-Chlorophenyl)-2-[(2-chlorophenyl)amino]-2-oxoethane-
hydrazonoyl Chloride (1e): This compound was prepared from 2-
chloroaniline (0.01 mol, 1.3 g) and 2-chloro-N-(2-chlorophenyl)-3-
oxobutanamide (0.01 mol, 2.5 g). Yield: 2.1 g (60%) of pale yellow,
1
needle felt from chloroform/heptane, m.p. 162Ϫ165 °C. H NMR
([D6]DMSO): see Table 5; additional signals: δ ϭ 7.03Ϫ7.94 (8 H,
arom. H). 13C NMR ([D6]DMSO): see Table 5; additional signals:
δ ϭ 117.0Ϫ137.7 (12 C, arom. C). MS (70 eV): m/z (%) ϭ 341 (50)
[Mϩ], 306 (22), 127 (100). C14H10Cl3N3O (342.62): calcd. C 49.08,
H 2.94, Cl 31.04, N 12.26; found C 48.63, H 2.81, Cl 31.05, N
12.20.
(1Z)-2-[(3-Chlorophenyl)amino]-N-naphthyl-2-oxoethanehydra-
zonoyl Chloride (1k): This compound was prepared from 1-naph-
thylamine (0.01 mol, 1.4 g) and 2-chloro-N-(3-chlorophenyl)-3-
oxobutanamide (0.01 mol, 2.5 g). The product was purified by dry
column chromatography, with toluene as eluent. Yield: 2.0 g (57%)
of brown prisms from chloroform/heptane, m.p. 172Ϫ175 °C. 1H
NMR ([D6]DMSO): see Table 5; additional signals: δ ϭ 7.17Ϫ8.22
(11 H, arom. H). 13C NMR ([D6]DMSO): see Table 5; additional
signals: δ ϭ 113.6Ϫ140.2 (16 C, arom. C). MS (70 eV): m/z (%) ϭ
357 (80) [Mϩ], 141 (100), 115 (65). C18H13Cl2N3O (358.32): calcd.
C 60.35, H 3.66, Cl 19.79, N 11.73; found C 60.17, H 3.59, Cl
19.87, N 11.71.
(1Z)-N-(3-Chlorophenyl)-2-[(2-chlorophenyl)amino]-2-oxoethane-
hydrazonoyl Chloride (1f): This compound was prepared from 3-
chloroaniline (0.01 mol, 1.3 g) and 2-chloro-N-(2-chlorophenyl)-3-
oxobutanamide (0.01 mol, 2.5 g). Yield: 1.9 g (55%) of fine, pale
yellow needles from chloroform/acetone, m.p. 206Ϫ209 °C. 1H
NMR ([D6]DMSO): see Table 5; additional signals: δ ϭ 6.99Ϫ7.80
(8 H, arom. H). 13C NMR ([D6]DMSO): see Table 5; additional
signals: δ ϭ 113.5Ϫ144.5 (12 C, arom. C). MS (70 eV): m/z (%) ϭ
341 (35) [Mϩ], 127 (100). C14H10Cl3N3O (342.62): calcd. C 49.08,
H 2.94, Cl 31.04, N 12.26; found C 48.63, H 2.76, Cl 30.52, N
12.26.
(1Z)-N-(3-Chlorophenyl)-2-[(4-chlorophenyl)amino]-2-oxoethane-
hydrazonoyl Chloride (1l): This compound was prepared from 3-
chloroaniline (0.01 mol, 1.3 g) and 2-chloro-N-(4-chlorophenyl)-3-
oxobutanamide (0.01 mol, 2.5 g). Yield: 3.1 g (90%) of pale yellow,
(1Z)-2-[(2-Chlorophenyl)amino]-N-(2-cyanophenyl)-2-oxoethane-
hydrazonoyl Chloride (1g): This compound was prepared from 2-
aminobenzonitrile (0.01 mol, 1.2 g) and 2-chloro-N-(2-chloro-
phenyl)-3-oxobutanamide (0.01 mol, 2.5 g). Yield: 2.1 g (63%) of
1
needle felt from chloroform/acetone, m.p. 200Ϫ204 °C. H NMR
([D6]DMSO): see Table 5; additional signals: δ ϭ 6.98Ϫ7.76 (8 H,
arom. H). 13C NMR ([D6]DMSO): see Table 5; additional signals:
δ ϭ 113.7Ϫ144.6 (12 C, arom. C). MS (70 eV): m/z (%) ϭ 341 (35)
[Mϩ], 127 (100), 99 (20). C14H10Cl3N3O (342.62): calcd. C 49.08, H
2.94, Cl 31.04, N 12.26; found C 48.89, H 2.91, Cl 31.01, N 12.17.
1
short, fine, yellow needles from chloroform, m.p. 165Ϫ167 °C. H
NMR ([D6]DMSO): see Table 5; additional signals: δ ϭ 7.14Ϫ7.84
(8 H, arom. H). 13C NMR ([D6]DMSO): see Table 5; additional
signals: δ ϭ 97.7 (s, 1 C, arom. CCN), 113.6Ϫ144.6 (12 C, CN and
arom. C). MS (70 eV): m/z (%) ϭ 332 (20) [Mϩ], 297 (100), 127
(100), 117 (50). C15H10Cl2N4O (333.18): calcd. C 54.08, H 3.02, Cl
21.28, N 16.81; found C 53.87, H 3.02, Cl 21.27, N 16.76.
X-ray Diffraction Analysis: The data collection was carried out with
a STOE-STADI-IV (1d) or a STOE-IPDS (1k) diffractometer.
Graphite-monochromated Mo-Kα radiation, and corrections for
Lorenz and polarisation were used. The structure was solved by
direct methods with the program SHELXS-86,[35] refinement was
carried out by a full-matrix, least-squares refinement with the pro-
gram SHELXL-93,[36] all non-hydrogen atoms anisotropic. Crystal-
lographic data are collected in Table 7. Crystallographic data
(1Z)-2-[(3-Chlorophenyl)amino]-2-oxo-N-phenylethanehydrazonoyl
Chloride (1h): This compound was prepared from aniline (0.01 mol,
0.93 g) and 2-chloro-N-(3-chlorophenyl)-3-oxobutanamide (0.01
mol, 2.5 g). Yield: 1.7 g (56%) of plate-like, yellow crystals from (excluding structure factors) for the structures reported in
chloroform/heptane, m.p. 171Ϫ173 °C. 1H NMR ([D6]DMSO): see
this paper have been deposited with the Cambridge Crystallo-
Table 5; additional signals: δ ϭ 7.01Ϫ7.88 (8 H, arom. H). 13C graphic Data Centre as supplementary publication nos. CCDC-
NMR ([D6]DMSO): see Table 5; additional signals: 169319 (1d) and -169320 (1k). Copies of the data can be obtained
δ
ϭ
114.9Ϫ142.8 (12 C, arom. C). MS (70 eV): m/z (%) ϭ 307 (95) free of charge on application to CCDC, 12 Union Road, Cam-
[Mϩ], 91 (100), 127 (95). C14H11Cl2N3O (308.17): calcd. C 54.57, H bridge CB2 1EZ, UK [Fax: (internat.) ϩ 44-1223/336-033; E-mail:
3.60, Cl 23.01, N 13.63; found C 54.40, H 3.67, Cl 22.98, N 13.70.
deposit@ccdc.cam.ac.uk].
Eur. J. Org. Chem. 2002, 1654Ϫ1663
1661

P. Frohberg, G. Drutkowski, C. Wagner
FULL PAPER
(62), 77 (56). C15H15N3O2 (269.31): calcd. C 66.90, H 5.61, N 15.60;
found C 66.61, H 5.63, N 15.33.
Table 7. Crystallographic data for 1d and 1k
1d
1k
[1]
[1a] A. S. Shawali, J. Heterocyclic Chem. 1980, 17, 833Ϫ854. [1b]
Empirical formula
Formula mass
Crystal system
Space group
C28H22Cll4N6O2
616.32
monoclinic
P21/a
C18H13Cl2N3O
358.21
monoclinic
P21/c
[1c]
A. S. Shawali, Chem. Rev. 1993, 93, 2731Ϫ2777.
G. Brog-
gini, G. Molteni, G. Zecchi, Heterocycles 1998, 47, 541Ϫ557.
[1d]
A. S. Shawali, M. A. Abdallah, Adv. Heterocycl. Chemistry
Temperature [K]
Cell dimensions
293
220
1995, 63, 277Ϫ338.
[2] [2a]
N. Prasad, A. Sahay, J. Prasad, K. R. K. Singh, Asian J.
˚
[2b]
a [A]
20.836(4)
4.870(3)
29.398(3)
110.265(11)
2798.4(18)
4
1.463
1.95Ϫ24.95
0.462
Ϫ25 Յ h Յ 24
0 Յ k Յ 5
Ϫ34 Յ l Յ 34
9474/4898
7.906(2)
22.452(6)
9.402(2)
96.92(3)
1656.8(7)
4
1.436
2.60Ϫ25.00
0.401
Ϫ9 Յ h Յ 9
Ϫ26 Յ k Յ 26
Ϫ11 Յ l Յ 11
11750/2835
Chem. 1996, 8, 357Ϫ360.
N. Prasad, A. Sahay, J. Prasad,
˚
b [A]
K. R. K. Singh, Asian J. Chem. 1996, 8, 65Ϫ74.
˚
[3] [3a]
c [A]
B. I. Buzykin, M. P. Sokolov, V. A. Pavlov, V. N. Ivanova,
β [°]
L. F. Chertanova, T. A. Zyablikova, Zh. Obshch. Khim. 1990,
3
˚
[3b]
Volume [A ]
Z
60, 546Ϫ555.
B. I. Buzykin, Z. S. Titova, V. D. Cherepin-
skii-Malov, N. G. Gazetdinova, A. P. Stolyarov, I. A. Litvinov,
Yu Struchkov, Yu Kitaev, Izv. Akad. Nauk SSSR, Ser. Khim.
1983, 541Ϫ549.
C. Reichardt, K. Halbritter, Chem. Ber. 1973, 106, 1661Ϫ1667.
A. F. Hegarty, M. T. McCormack, B. J. Hathaway, L. Hulett,
J. Chem. Soc., Perkin Trans. 2 1977, 9, 1136Ϫ1141.
R. C. Seccombe, C. H. L. Kennard, Aust. J. Chem. 1970, 23,
395Ϫ397.
ρ [g·cm3]
θ range [°]
µ [mmϪ1]
Limiting indices
[4]
[5]
[6]
Reflections
[7] [7a]
collected/unique
Reflections with
I Ͼ 2σ(I)
R(int)
parameters
V. D. Cherepinskii-Malov, B. I. Buzykin, A. I. Gusev, Izv.
[7b]
3416
2387
Akad. Nauk SSSR Ser. Khim. 1981, 2716Ϫ2719.
V. D.
Cherepinskii-Malov, B. I. Buzykin, J. P. Kitajev, J. T.
Strutschkov, Izv. Akad. Nauk SSSR Ser. Khim. 1975, 805Ϫ811.
J. E. Rowe, D. A. Papanelopoulos, Aust. J. Chem. 1995, 48,
2041Ϫ2046.
0.0358
449
0.0447; 0.0970
0.0781; 0.1138
0.202; Ϫ0.286
0.0352
269
0.0355; 0.0848
0.0429; 0.0886
0.453; Ϫ0.432
[8]
R1; wR2 [I Ͼ 2σ(I)]
R1; wR2 (all data)
[9]
J. E. Rowe, A. F. Hegarty, J. Org. Chem. 1984, 49, 3083Ϫ3087.
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Ϫ3
˚
[10]
ρmax; ρmin [eA
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(1Z)-2-Anilino-N-methyl-2-oxo-N-phenylethanehydrazonoyl Chlor-
ide (2): This compound was synthesised according to a published
procedure.[37] 2-(2-Methyl-2-phenyl)hydrazino-2-oxoacetanilide (9,
7 mmol, 2.0 g) was suspended in 80 mL of toluene. Phosphorus
pentachloride (14 mmol, 2.9 g) was added to the stirred suspension
at room temperature. The mixture was stirred at 50 °C until the
reaction was complete (monitored by TLC; hexane/ether, 7:3) and
then poured onto crushed ice. The organic layer was separated, and
the aqueous layer was washed twice with ether. The organic solu-
tion was dried, the solvent was removed, and the crude product
was purified by dry column chromatography, with toluene as elu-
ent. Yield: 0.9 g, (46%) of light yellow needles from heptane, m.p.
126Ϫ131 °C. 1H NMR ([D6]DMSO): see Table 5; additional sig-
nals: δ ϭ 3.72 (s, 3 H, CH3), 7.06Ϫ7.70 (10 H, arom. H). 13C NMR
([D6]DMSO): see Table 5; additional signals: δ ϭ 41.1 (s, 1 C,
CH3), 117.5Ϫ147.9 (12 C, arom. C). MS (70 eV): m/z (%) ϭ 287
(45) [Mϩ], 105 (100), 77 (51). C15H14ClN3O (287.75): calcd. C
62.61, H 4.90, Cl 12.32, N 14.60; found C 62.30, H 4.91, Cl 12.36,
N 14.52.
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L. J. Powers, S. W. Fogt, Z. S. Ariyan, D. J. Rippin, R. D.
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H. V. Patel, K. A. Vyas, S. P. Pandey, P. S. Fernandes, Tetrahed-
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[19]
[20]
2-(2-Methyl-2-phenyl)hydrazino-2-oxoacetanilide (9): The synthesis
was based on ref.[38] 1-Methyl-1-phenylhydrazine (0.02 mol, 2.4 g)
and 2-anilino-2-oxoacetyl chloride (0.02 mol, 3.7 g) in toluene were
stirred at room temperature until completion of reaction, as mon-
itored by TLC (hexane/ethyl acetate, 7:3). Yield: 2.7 g (50%) of an
amorphous solid from chloroform/heptane, m.p. 229Ϫ231 °C. IR
(KBr): ν˜ ϭ 3300, 3244 (NH ass.), 1755 (CϭO, amide, hydrazide),
1H NMR ([D6]DMSO): δ ϭ 3.13 (s, 3 H, CH3), 6.77Ϫ7.83 (10 H,
arom. H), 10.69 (s, 1 H, CONH, amide), 11.00 (s, 1 H, CONHN,
hydrazide). 13C NMR ([D6]DMSO): δ ϭ 39.9 (CH3), 112.7Ϫ149.3
(12 C, arom. C), 158.8 (CONH, amide), 159.9 (CONHN,
hydrazide). MS (70 eV): m/z (%) ϭ 269 (100) [Mϩ], 148 (53), 121
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1662
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Patent, Kumiai Chemical Industry Co., Ltd. JP 61249990;
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1663