1,2-Bis[(2-dimethylamino-2-thioxo-1-phenylethylidene)hydrazino]ethane: A new tetradentate ligand for Ni2+

Article abstract of DOI:10.1039/b101030l

The preparation of a new type of N₂S₂ tetradentate ligand 3 with the bis(hydrazonothioamide) structure is reported in this paper. The key step in this synthesis is the condensation of the dihydrazine 7 with an α-ketoester. Ligand {1,2-bis[(2-dimethylamino-2-thioxo-1-phenylethylidene)hydrazino]ethane} 3 was obtained in 6 steps from secondary amine. This ligand is then used in the preparation of a nickel(II) complex 4 and the mesomeric forms of metallic complex NiN₂S₂ are discussed.

Full text of DOI:10.1039/b101030l

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1,2-Bis[(2-dimethylamino-2-thioxo-1-phenylethylidene)hydrazino]-
ethane: a new tetradentate ligand for Ni2؉
Jean-Damien Charrier, David Deniaud, Alain Reliquet and Jean-Claude Meslin*
1
Laboratoire de Synthèse Organique, Faculté des Sciences et des Techniques,
UMR C.N.R.S. 6513, BP 92208, 2, rue de la Houssinière, F44322, Nantes Cedex 03, France
Received (in Cambridge, UK) 29th January 2001, Accepted 2nd April 2001
First published as an Advance Article on the web 24th April 2001
The preparation of a new type of N2S2 tetradentate ligand 3 with the bis(hydrazonothioamide) structure is reported
in this paper. The key step in this synthesis is the condensation of the dihydrazine 7 with an α-ketoester. Ligand
{1,2-bis[(2-dimethylamino-2-thioxo-1-phenylethylidene)hydrazino]ethane} 3 was obtained in 6 steps from secondary
amine. This ligand is then used in the preparation of a nickel() complex 4 and the mesomeric forms of metallic
complex NiN2S2 are discussed.
Reduction of the dinitrosoamine 6 with a titanium complex,
generated in situ by the action of magnesium on titanium()
Introduction
Polyamine tetradentate ligands are very important synthetic
intermediates and their metal complexes have attracted con-
chloride, afforded the corresponding dihydrazine 7 in 98% yield
(Scheme 1).12,13
siderable attention as models for natural tetraazamacrocycles,1
as contrast agents for magnetic resonance imaging2 and for use
in nuclear medicine.3 These ligands have been extensively
described in the literature. N2S2 tetradentate ligands are rarer
and only a few have been reported.4 Bis(aminopropenethiones)
1 first prepared by Holm5 are the most common type of N2S2
ligand. This type of ligand has been shown to complex metal
cations6 such as Ni2+, Cu2+, Co2+, Mn2+, Zn2+ and Tc2+ and
the resulting complexes have been shown to have medical
applications.7
In the course of our studies on 4-amino-1-thia-4-azabuta-
dienes, we have shown that α-hydrazonothioamides 2 are stable
Scheme 1 Reagents and conditions: (i) NaNO2–HCl, H2O, 100 ЊC,
and can be easily synthesised in high yields.8 This stability
20 h; (ii) TiCl4–Mg, CH2Cl2–Et2O, rt, 5 h.
recently prompted us to prepare a new type of N2S2 tetra-
dentate ligand 3 which is a bis(hydrazonothioamide).9 We
The protected dihydrazine 7 was then reacted with two
report here the synthesis of compound 3 and the behaviour of
this tetradentate ligand towards Ni2+ to afford the metallic
complex 4.
equivalents of methyl benzoylformate to furnish the bis-
(hydrazonoester) 8 in 81% yield. Thionation of this precursor
of the N2S2 ligand using Lawesson’s reagent proved to be
unsuccessful. However, we have shown that α-hydrazonoamides
are easily converted into their thionated analogues 2 using
Lawesson’s reagent,8 and so the bis(hydrazonoester) 8 was
transformed into the bis(hydrazonoamide) 9 by the action of
dimethylaluminium dimethylamide, formed in situ by addition
of dimethylamine to trimethylaluminium (Scheme 2).14
The compound 9 was prepared in 91% yield. Hydrogenolysis
of the benzyl protecting groups was complicated by con-
comitant N–N bond cleavage (Scheme 3). Optimisation of the
conditions involved variation of solvents, length of reaction
time, ratios of catalyst to substrate and ratios of reagent to
substrate. In each case, a mixture of monodeprotected com-
pound 11 (recyclable), desired product 10 and the compound
of decomposition 12 was obtained. Optimal conditions for
yielding the deprotected N2O2 ligand 10 in 53% yield were
found to be the use of 4.5 equivalents of formic acid in meth-
anol with an equal amount of 10% palladium on charcoal.15
Thionation of the compound 10 with Lawesson’s reagent
afforded the N2S2 tetradentate ligand 3 in 84% yield.
Results and discussion
The key step in the preparation of the bis(hydrazonothioamide)
3 was the condensation of an α-ketoester with the dihydrazine
7. The latter compound was prepared from secondary amines10
via the corresponding dinitrosoamines 6 in a well known two-
step sequence to give high yields: the protected diamine 5 was
transformed into the dinitrosoamine 6 in 98% yield by addition
of sodium nitrite to the dihydrochloride of the diamine.11
Complexation of N2S2 tetradentate ligands with metallic
cations has been described in previous works6 and the method
consisted of dissolving the ligand in the minimum amount of
chloroform and adding a solution of the metal acetate in
methanol dropwise. The metallic complex, insoluble in the
1212
J. Chem. Soc., Perkin Trans. 1, 2001, 1212–1215
This journal is © The Royal Society of Chemistry 2001
DOI: 10.1039/b101030l

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Unlike ligands of the type bis(aminopropenethione) 1, 3 was
highly specific for Ni2+ since all attempts to complex other
metallic cations proved to be totally unsuccessful. Thus,
reaction of 3 with Mn2+, Cu2+, Co2+ or Zn2+ did not yield
the corresponding metallic complexes under the conditions
described above. This failure is surprising, particularly with
copper. Indeed, comparison between Cu2+ and Ni2+complexes is
justified by the similar size of these two elements (0.63 Å for
Ni2+ versus 0.71 Å for Cu2+ in a square planar environment)16
and by their nearly identical complexation constants.17 On the
basis of the behaviour of these two elements in coordination
chemistry, we can expect square planar complexes with nickel16
while for copper complexes tetrahedral environments have
usually been observed (planar environments are possible with
orthogonal anionic ligands).18 In our case, we have not
observed the formation of the complex of CuN2S2. It is
suggested that the nature of the ligand might have a crucial
influence on the geometry of the complex and perhaps a larger
distortion from the plane cannot be tolerated.
It should be noted that a change in the electron environment
(ligand 10) and the variation in chain length (ligand 13)19 have
an important influence on the formation of these complexes. In
our hands, the metallic complexes failed to form with these
ligands.
Scanning electron microscopy was consistent with the
proposed structure and gave a ratio S : Ni = 2. Nevertheless, 4
can in fact be written in two mesomeric forms 4a and 4b
(Scheme 4) and nuclear magnetic resonance was used to afford
Scheme 2 Reagents and conditions: (i) CH3CO2H, MeOH, reflux, 24 h;
(ii) Me2NH, AlMe3, C6H6, 0 ЊC to rt, 30 min; (iii) HCO2H, 10% Pd on
C, MeOH, rt, 2 h; (iv) Lawesson’s reagent, C6H6, reflux, 20 h; (v)
Ni(OAc)2, MeOH–CHCl3, rt, 20 h.
Scheme 4
more information about the electron distribution in the
complex. Proton and carbon NMR showed that the non-
equivalence of the two methyl groups in the ligand 3, consistent
with the presence of a thioamide function, disappeared in 4;
moreover, the chemical shift for CH2N changed from 50.5 ppm
in 3 to 63.5 ppm in 4, the latter value is in agreement with the
shift expected for Nsp2–CH2. Finally, the large difference of
chemical shift in C᎐S (193.3 ppm in 3 to 161.3 ppm in 4) could
᎐
be attributed to a decrease in the bond order. All these
arguments seem to show that the complex 4 is more likely to
exist as form 4b. To fully characterise the mesomeric form we
would like to perform a crystal structure analysis but complex 4
exists as an amorphous powder.
In conclusion, we have prepared a new type of ligand N2S2 in
7 steps with an overall yield of 25%. This ligand has a high
selectivity for Ni2+ compared with other metallic cations and
the metallic complex 4 has been shown to be in the form 4b
rather than 4a.
Scheme 3
Experimental
All reagents were purchased from Acros Organics and Aldrich.
The C.N.R.S. Analysis Laboratory (Vernaison) performed the
elemental analyses. Column chromatography was conducted on
binary system of solvents, was simply collected by filtration.
This procedure was remarkably successful in complexing the
ligand 3 with Ni2+ to afford the metallic complex NiN2S2 4 in
79% yield after crystallisation.
J. Chem. Soc., Perkin Trans. 1, 2001, 1212–1215
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silica gel 60 (40–63 µm), available from E. Merck. Thin layer
chromatography was performed on 0.5 mm × 20 cm × 20 cm E.
Merck silica gel plates (60 F-254). Melting points measured
using a Reichert microscope were uncorrected. The 13C and
1H NMR spectra were recorded at room temperature using a
Bruker AC200 at 50 and 200 MHz respectively. Chemical shifts
(δ) are given in ppm downfield from tetramethylsilane as
internal standard. Mass spectra were determined with a
Hewlett Packard 5989 spectrometer. The IR spectra were
obtained using a Bruker Vector22 spectrometer.
refluxed for 24 h and cooled to room temperature. Solvents
were evaporated and the residue was dissolved in ethyl acetate
(20 mL) and extracted. The organic phase was washed with
saturated aqueous sodium hydrogen carbonate, brine, dried
(MgSO4), filtered and evaporated. The residue was purified by
chromatography on silica using dichloromethane as eluent.
Compound 8 was crystallised from diethyl ether (81%); mp
95 ЊC (Found: C, 72.45; H, 5.94; N, 9.91. C34H34N4O4 requires
C, 72.58; H, 6.09; N, 9.96%); NMR spectra of compound 8
showed 2 symmetric rotamers A and C and 1 dissymmetric
rotamer B. 1H NMR (CDCl3) δ 2.97 and 3.20 (B, 2t, 4H,
2NCH2CH2), 3.08 (A, s, 4H, 2NCH2CH2), 3.40 (C, s, 4H,
2NCH2CH2), 3.68 (A, s, 6H, 2OCH3), 3.70 (B, s, 6H, 2OCH3),
3.74 (C, s, 6H, 2OCH3), 3.92 and 4.38 (B, 2s, 4H, 2CH2Ph), 4.06
(A, s, 4H, 2CH2Ph), 4.24 (C, s, 4H, 2CH2Ph), 6.91–7.60
(A + B + C, m, 20H, CHar); 13C NMR (CDCl3) δ 51.63 (C,
2C, 2OCH3), 51.75 and 51.99 (B, 2C, 2OCH3), 52.07 (A, 2C,
2OCH3), 53.03 and 53.50 (B, 2C, 2NCH2CH2), 54.11 (A,
2C, 2NCH2CH2), 54.56 (C, 2C, 2NCH2CH2), 59.00 (A, 2C,
2CH2Ph), 60.46 and 62.49 (B, 2C, 2CH2Ph), 62.27 (C, 2C,
2CH2Ph), 126.61, 126.77, 127.05, 127.08, 127.20, 127.23,
127.32, 127.39, 127.50, 127.58, 127.69, 127.96, 128.09, 128.24,
128.36, 128.38, 128.46, 128.52, 128.87, 129.00, 129.42, 129.50,
130.01, 130.51 (A + B + C, 20CHar), 129.83, 131.20, 132.40,
132.95, 134.76, 135.07, 136.16, 136.64, 136.68, 137.02, 153.90,
N,NЈ-Dibenzyl-N,NЈ-dinitroso-1,2-diaminoethane 6
To a solution of N,NЈ-dibenzyl-1,2-diaminoethane 5 (10Ϫ2 mol)
in water (80 mL) was added 12 M hydrochloric acid (5 × 10Ϫ2
mol). The reaction mixture was heated to reflux and sodium
nitrite (2.4 × 10Ϫ2 mol) in water (10 mL) was added dropwise
over 10 min. The solution was refluxed for 20 h, cooled to room
temperature and extracted with dichloromethane (100 mL × 2).
The organic phase was washed with brine, dried (MgSO4),
filtered and evaporated. Compound 6 was crystallized from
ethyl acetate (98%); mp 75 ЊC (Found: C, 64.12; H, 6.11; N,
19.06. C16H18N4O2 requires C, 64.41; H, 6.08; N, 18.78%);
NMR spectra of compound 6 showed 3 rotamers A, B and C.
1H NMR (DMSO-d6) δ 3.39 (A, s, 4H, 2NCH2CH2), 3.74
and 3.98 (B, 2t, 4H, 2NCH2CH2, J 6.1 Hz), 4.33 (C, s, 4H,
2NCH2CH2), 4.69 and 5.23 (B, 2s, 4H, 2CH2Ph), 4.75 (C, s,
4H, 2CH2Ph), 5.16 (A, s, 4H, 2CH2Ph), 7.04–7.42 (A + B +
C, m, 10H, CHar); 13C NMR (DMSO-d6) δ 39.45 (A, 2C,
2NCH2CH2), 41.14 and 46.76 (B, 2C, 2NCH2CH2), 48.61 (C,
2C, 2NCH2CH2), 46.09 (C, 2C, 2CH2Ph), 46.48 and 56.35 (B,
2C, 2CH2Ph), 56.48 (A, 2C, 2CH2Ph), 128.01, 128.09, 128.27,
128.29, 128.37, 128.66, 128.74, 128.85, 128.93, 128.99, 129.10
(A + B + C, 10CHar), 133.39 (C, 2Car), 133.63 and 133.90 (B,
2Car), 133.93 (A, 2Car); MS, m/z (%) 268 (9, (M Ϫ NO)+), 238
(9, (M Ϫ 2NO)+), 118 (22), 92 (10), 91 (100); IR/cmϪ1 (KBr)
1496 (m), 1453 (w), 1416 (m), 1369 (w), 1353 (vw), 1300 (w),
1279 (w), 1173 (m), 1152 (m), 1104 (w), 1074 (w), 1029 (m), 941
(m), 866 (m), 791 (m), 743 (m), 703 (vw), 681 (m).
156.67 (A + B + C, 4Car + 2C᎐N), 165.93 and 166.22 (B,
᎐
2C᎐O), 166.08 (A, 2C᎐O), 166.19 (C, 2C᎐O); MS, m/z (%) 562
᎐
᎐
᎐
(<1, M+), 400 (3), 340 (6), 281 (22), 237 (10), 235 (8), 133 (13),
92 (8), 91 (100); IR/cmϪ1 (KBr) 1700 (vw), 1560 (w), 1496 (m),
1431 (w), 1319 (m), 1283 (vw), 1216 (w), 1140 (w), 1109 (w),
1075 (m), 1049 (w), 1023 (m), 959 (m), 942 (m), 730 (m), 718
(w), 696 (w).
1,2-Bis[(2-dimethylamino-2-oxo-1-phenylethylidene)-N-benzyl-
hydrazino]ethane 9
To a solution of trimethylaluminium (21 mmol) in benzene (25
mL) was added dimethylamine (20 mmol) at 0 ЊC under N2. The
reaction was stirred at 0 ЊC for 20 min and allowed to warm to
room temperature over 45 min. Compound 8 (5 mmol) was
added and the reaction mixture was refluxed for 20 h, cooled to
room temperature and hydrolysed by dropwise addition of
dilute hydrochloric acid (21 mmol). The reaction mixture was
extracted with ethyl acetate and the organic phase was washed
with saturated aqueous sodium hydrogen carbonate, brine,
dried (MgSO4), filtered and evaporated. The residue was
purified by chromatography on silica using a mixture of
dichloromethane–ethyl acetate (9 : 1) as eluent. Compound 9
was crystallized from ethyl acetate (91%); mp 127 ЊC (Found: C,
73.51; H, 6.79; N, 14.23. C36H40N6O2 requires C, 73.44; H, 6.85;
N, 14.27%); 1H NMR (C6D6) (recorded at 60 ЊC) δ 2.28 and 2.65
(2s, 12H, 2N(CH3)2), 3.50 (br s, 4H, 2NCH2CH2), 4.23 and 4.57
(2br s, 4H, 2CH2Ph), 7.04–7.20, 7.32–7.37 and 7.80–7.85 (3m,
20H, CHar); 13C NMR (C6D6) (recorded at 60 ЊC) δ 33.60 and
36.82 (4C, 2N(CH3)2), 55.73 (2NCH2CH2), 61.53 (2CH2Ph),
126.14, 126.98, 128.17, 128.44, 128.77, 129.18 (20CHar),
N,NЈ-Diamino-N,NЈ-dibenzyl-1,2-diaminoethane 7
Titanium() chloride (0.16 mol) was slowly added under N2 to
a mixture of dichloromethane–diethyl ether (4 : 1) (250 mL).
Magnesium turnings (0.16 mol) were added and the reaction
mixture was stirred at room temperature for 3 h. Dinitroso-
amine 6 (2×10Ϫ2 mol) was added to the black suspension and
the reaction was stirred for a further 45 min, 0.3 M (41 mL)
hydrochloric acid was added and the reaction was stirred for
another hour. The reaction mixture was made alkaline by
addition of dilute sodium hydroxide. The mixture was filtered
through a pad of Celite and the filtrate was extracted with
dichloromethane (300 mL). The organic phase was washed with
brine, dried (MgSO4), filtered and evaporated. Compound 7
was crystallised from ethanol (98%); mp 62 ЊC (Found: C,
71.47; H, 8.33; N, 20.56. C16H22N4 requires C, 71.11; H, 8.15; N,
20.74%); 1H NMR (CDCl3) δ 2.83 (s, 8H, 2NCH2CH2 + 2NH2),
3.72 (s, 4H, 2CH2Ph), 7.25–7.36 (m, 10H, CHar); 13C NMR
(CDCl3) δ 58.03 (2C, 2NCH2CH2), 66.79 (2C, 2CH2Ph),
127.53, 128.60, 129.47 (10CHar), 137.77 (2Car); IR/cmϪ1 (KBr)
3128 (m), 2814 (m), 1604 (m), 1496 (m), 1456 (w), 1368 (m),
1330 (m), 1296 (m), 1243 (m), 1163 (m), 1051 (w), 1028 (m),
1007 (w), 989 (w), 912 (m), 841 (m), 825 (m), 800 (m), 735 (vw),
700 (vw).
134.87, 138.42 (4Car), 151.25 (2C᎐N), 167.53 (2C᎐O); MS, m/z
᎐
᎐
(%) 413 (12), 294 (11), 237 (32), 104 (11), 91 (100), 72 (80), 58
(53); IR/cmϪ1 (KBr) 1636 (vw), 1494 (m), 1445 (m), 1404 (m),
1253 (m), 1151 (m), 960 (m), 741 (m), 719 (m), 698 (w).
1,2-Bis[(2-dimethylamino-2-oxo-1-phenylethylidene)hydrazino]-
ethane 10
To a suspension of 9 (1 mmol) in methanol (10 mL) was added
formic acid (4.5 mmol) at room temperature. An equal amount
(589 mg) of 10% palladium on charcoal was added and the
reaction mixture was stirred for 2 h at room temperature. The
mixture was filtered through a pad of Celite and the cake was
washed with ethyl acetate. The solvents were evaporated and
the residue was purified by chromatography on silica using a
1,2-Bis[(2-methoxy-2-oxo-1-phenylethylidene)-N-benzyl-
hydrazino]ethane 8
To a solution of methyl benzoylformate (2.1 × 10Ϫ2 mol) and
acetic acid (2.1 × 10Ϫ2 mol) in methanol (20 mL) was added the
dihydrazine 7 at room temperature, under N2. The solution was
1214
J. Chem. Soc., Perkin Trans. 1, 2001, 1212–1215

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mixture of ethyl acetate–acetone (19 : 1) as eluent. Compound
10 was crystallised from ethyl acetate (53%); mp 180 ЊC (Found:
C, 64.71; H, 6.86; N, 20.59; O, 7.84. C22H28N6O2 requires C,
(22); IR/cmϪ1 (KBr) 1136 (vw), 1066 (vw), 994 (w), 956 (m), 853
(m), 794 (m), 725 (m).
1
64.64; H, 6.91; N, 20.67; O, 7.94%); H NMR (CDCl3) δ 2.78
Acknowledgements
and 3.00 (2s, 12H, 2N(CH3)2), 3.48 (m, 4H, 2NCH2CH2), 5.95
(br s, 2H, 2NH), 7.14–7.32 and 7.43–7.48 (2m, 10H, CHar); 13
C
The authors wish to express their gratitude to the French
Ministry of Education and C.N.R.S. for financial support.
NMR (CDCl3) δ 33.77 and 36.98 (4C, 2N(CH3)2), 50.30
(2NCH2CH2), 124.85, 128.24, 128.58 (10C CHar), 134.18
(2Car), 141.65 (2C᎐N), 166.03 (2C᎐O); MS, m/z (%) 408 (6,
᎐
᎐
M+), 205 (29), 204 (27), 178 (13), 177 (100), 131 (30), 105 (12),
104 (52), 77 (14), 72 (52), 58 (21), 44 (10); IR/cmϪ1 (KBr) 3260
(w), 2928 (m), 1626 (vw), 1561 (m), 1483 (w), 1444 (m), 1395
(w), 1260 (m), 1181 (m), 1117 (w), 1052 (m), 728 (m), 701 (m).
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1,2-Bis[(2-dimethylamino-2-thioxo-1-phenylethylidene)-
hydrazino]ethane 3
To a solution of 10 (0.75 mmol) in benzene (3 mL) was added
Lawesson’s reagent (0.97 mmol) at room temperature. The
reaction mixture was refluxed for 20 h and cooled to room
temperature. The solvents were evaporated and the residue was
purified by chromatography on silica using dichloromethane as
eluent. Compound 3 was crystallised from diethyl ether (84%);
mp 183 ЊC (Found: C, 59.92; H, 6.37; N, 19.21; S, 14.61.
C22H28N6S2 requires C, 60.00; H, 6.36; N, 19.09; S, 14.55%); 1H
NMR (CDCl3) δ 3.09 and 3.49 (2s, 12H, 2N(CH3)2), 3.53 (m,
4H, 2NCH2CH2), 5.70 (br s, 2H, 2NH), 7.28–7.31 and 7.56–
7.59 (2m, 10H, CHar); 13C NMR (CDCl3) δ 40.85 and 42.38
(4C, 2N(CH3)2), 50.51 (2NCH2CH2), 124.94, 128.19, 128.39
6 (a) B. Adélaère, PhD Thesis, University of Nantes, 1989; (b)
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10 W. Sucrow, Methodicum Chimicum, ed. F. Korte, Georg Thieme
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13 CAUTION! Nitrosoamines and hydrazines are carcinogenic agents.
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(10CHar), 133.95 (2Car), 144.53 (2C᎐N), 193.35 (2C᎐S); MS,
᎐
᎐
m/z (%) 440 (2, M+), 249 (19), 248 (100), 221 (14), 220 (34), 219
(72), 193 (44), 192 (19), 191 (34), 176 (10), 149 (11), 145 (43),
131 (12), 121 (17), 104 (36), 103 (12), 90 (16), 89 (34), 88 (52), 77
(13), 44 (17), 42 (11); IR/cmϪ1 (KBr) 3240 (m), 1582 (m), 1554
(w), 1522 (vw), 1494 (m), 1475 (w), 1445 (m), 1406 (m), 1393
(w), 1324 (m), 1304 (m), 1263 (w), 1145 (vw), 1098 (w), 1028
(m), 941 (m), 759 (w), 690 (w).
1,2-Bis[(2-dimethylamino-2-thioxo-1-phenylethylidene)-
hydrazino]ethane nickel(II) 4
15 B. D. Gray and P. W. Jeffs, J. Chem. Soc., Chem. Commun., 1987, 18,
1329.
To a solution of 3 (0.2 mmol) in chloroform (2 mL) was added
Ni(OAc)2ؒ4H2O (0.22 mmol) in methanol (5 mL) at room
temperature. The reaction mixture was stirred for 2 h at room
temperature and the brown precipitate was filtered and washed
with methanol. Compound 4 was crystallised from a mixture of
methanol–chloroform (79%); mp > 300 ЊC (Found: C, 53.18;
H, 5.32; N, 17.08; S, 13.15. C22H26N6NiS2 requires C, 53.13; H,
16 F. A. Cotton and G. Wilkinson, Advanced Inorganic Chemistry,
Wiley and Sons, New York, 5th edn., 1988, p. 1385.
17 G. Anderegg, in Comprehensive Coordination Chemistry, ed.
G. Wilkinson, R. D. Gillard and J. A. McCleverty, Pergamon Press,
Oxford, 1987, vol. 2, p. 777.
18 M. Zehnder, C. Bolm, S. Schaffner, D. Kaufmann and J. Müller,
Liebigs Ann., 1995, 125.
1
5.27; N, 16.90; S, 12.89%); H NMR (CDCl3) δ 2.91 (s, 12H,
19 1,2-Bis[(2-dimethylamino-2-thioxo-1-phenylethylidene)hydrazino]-
propane 13: mp 117 ЊC; 1H NMR (CDCl3) δ 1.93 (q, J 6.4, 2H), 3.06
and 3.49 (2s, 12H), 3.40 (t, J 6.4, 4H), 5. 83 (br s, 2H), 7.24–7.34 and
7.54–7.58 (2m, 10H); 13C NMR (CDCl3) δ 30.13, 40.76 and 42.15
(2C), 47.84 (2C), 124.70, 127.93, 128.30 (10C), 133.97 (2C), 143.40
(2C), 193.52 (2C); MS, m/z (%) 455 (7, (M + 1)+), 263 (29), 262 (100),
261 (19), 249 (45), 246 (12), 245 (55), 234 (11), 220 (34), 219 (21), 218
(88), 207 (19), 206 (58), 205 (15), 194 (13), 193 (85), 192 (12), 191
(45), 178 (21), 177 (91), 176 (33), 149 (12), 148 (12), 145 (28), 144
(13), 135 (10), 134 (13), 131 (17), 130 (38), 122 (16), 121 (45), 104
(46), 103 (17), 91 (25), 90 (25), 89 (41), 88 (80), 77 (17), 74 (13), 71
(13), 58 (13), 56 (13), 44 (50), 42 (24); IR/cmϪ1 (KBr) 3242 (m), 2931
(w), 2856 (m), 1520 (vw), 1494 (m), 1445 (m), 1393 (w), 1319 (m),
1300 (m), 1261 (w), 1142 (vw), 1100 (s), 1074 (m), 1028 (m), 766 (m),
692 (w).
2N(CH3)2), 3.73 (s, 4H, 2NCH2CH2), 7.13 and 7.31 (2m,
10H, CHar); 13C NMR (CDCl3) δ 45.45 (4C, 2N(CH3)2), 63.50
(2NCH2CH2), 125.36, 127.79, 128.39 (10C, CHar), 129.03
(2Car), 142.02 (2C᎐N), 161.34 (2C᎐S); MS, m/z (%) 500 (11,
᎐
᎐
+
60
+
60
+
ؒ
ؒ
ؒ
(M + 2) / Ni), 499 (15, (M + 1) / Ni), 498 (54, M /
60
+
58
+
58
+
ؒ
ؒ
ؒ
Ni + (M+2) / Ni), 497 (28, (M + 1) / Ni), 496 (100, M /
58Ni), 470 (11), 468 (21), 367 (38), 366 (15), 365 (77), 338 (46),
279 (17), 278 (11), 277 (34), 252 (11), 251 (31), 250 (22), 249
(70), 248 (23), 236 (34), 235 (14), 234 (74), 225 (16), 223 (37),
221 (12), 219 (22), 192 (22), 179 (12), 161 (18), 149 (30), 148
(33), 147 (62), 146 (70), 145 (12), 144 (17), 131 (13), 121 (26),
104 (26), 103 (25), 101 (17), 89 (32), 88 (27), 77 (15), 58 (21), 44
J. Chem. Soc., Perkin Trans. 1, 2001, 1212–1215
1215