Preparation of cyanoguanidine and ethylcyanamide complexes of ruthenium(II) and osmium(II)

Article abstract of DOI:10.1002/ejic.200900639

Cyanoguanidine complexes [MCl{η¹-N=CN(H)C(NH ₂)=NH}(η⁶-p-cymene)(PR3)]BPh₄ [M = Ru, Os; PR₃ = P(OEt)₃, PPh(OEt)₂, PPh₂OEt, PiPr₃] were prepared, by treating

Full text of DOI:10.1002/ejic.200900639

FULL PAPER
DOI: 10.1002/ejic.200900639
Preparation of Cyanoguanidine and Ethylcyanamide Complexes of
Ruthenium(II) and Osmium(II)
Gabriele Albertin,*[a] Stefano Antoniutti,[a] and Jesús Castro[b]
Keywords: Cyanamides / Ruthenium / Osmium / P ligands / N ligands
Cyanoguanidine complexes [MCl{η1-NϵCN(H)C(NH2)=NH}- BPh4 were also obtained by treating [MCl2(η6-p-cymene)-
(η6-p-cymene)(PR3)]BPh4 [M
Ru, Os; PR3 P(OEt)3, (PR3)] with an excess amount of NϵCNEt2. Complexes were
=
=
1
PPh(OEt)2, PPh2OEt, PiPr3] were prepared by treating com- characterised spectroscopically (IR, H, 31P, 13C NMR) and in
pounds
[MCl2(η6-p-cymene)(PR3)]
with
cyanamide
the case of [RuCl{NϵCN(H)C(NH2)=NH}(η6-p-cymene)-
{PPh(OEt)2}]BPh4 by X-ray crystal structure determination.
NϵCNH2. Alternatively, complexes [MCl{η1-NϵCN(H)C-
(NH2)=NH}(η6-p-cymene)(PR3)]BPh4 were prepared by treat-
ing [MCl2(η6-p-cymene)(PR3)] with cyanoguanidine. Diethyl-
cyanamide complexes [MCl(NϵCNEt2)(η6-p-cymene)(PR3)]-
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2009)
Introduction
Results and Discussion
Cyanamides NϵCNR2 (R = H, alkyl or aryl) are amino-
functionalised nitriles whose coordination chemistry is still
relatively unexplored[1–7] in comparison to the rich and vari-
ous coordination chemistry of organonitriles RCϵN (R =
alkyl or aryl).[8]This is somewhat surprising in light of the
biological and synthetic interest of these compounds, par-
ticularly cyanamide itself, NϵCNH2, and its dimeric form,
cyanoguanidine, NϵCN(H)C(NH2)=NH.[9,10] Only a small
number of papers on the synthesis and reactivity of cyana-
mide complexes of transition metals have recently been re-
ported, mainly molybdenum,[6] platinum,[5] and copper[4] as
central metal. Instead, only one report is known for ruthe-
nium[11] and none for osmium.
p-Cymene complexes of ruthenium and osmium
[MCl2(η6-p-cymene)(PR3)][24a] react with an excess amount
of cyanamide, NϵCNH2, in the presence of NaBPh4, to
give cyanoguanidine complexes [MCl{NϵCN(H)C-
(NH2)=NH}(η6-p-cymene)(PR3)]BPh4 (1 and 3), as shown
in Scheme 1.
We are interested in the chemistry of “diazo” and “tri-
azo” complexes of transition metals with d6 configuration
and have reported the synthesis not only of diazene and
hydrazine derivatives[12] but also of amidrazone complexes
obtained by nucleophilic attack of hydrazine on coordi-
nated nitrile.[13] We have now extended these studies to cy-
anamide, and this paper reports the preparation of cyano-
guanidine and diethylcyanamide complexes of ruthenium
and osmium stabilised by half-sandwich p-cymene frag-
ments.
Scheme 1. M = Ru (1), Os (3); PR3 = P(OEt)3 (a), PPh(OEt)2 (b),
PPh2OEt (c), PiPr3 (d).
Cyanoguanidine complexes 1 and 3 were also prepared
by treating the dichloride precursor [MCl2(η6-p-cym-
ene)(PR3)] with an excess amount of free cyanoguanidine,
NϵCN(H)C(NH2)=NH, in ethanol. In both cases, the re-
action proceeds with substitution of one chloride by the N-
donor ligand, yielding cationic complexes 1 and 3.
The formation of cyanoguanidine complexes 1 and 3
from the reaction of cyanamide is not unexpected and may
be explained on the basis of the initial coordination of one
molecule of NϵCNH2 to give cyanamide complex [A]
(Scheme 2). Nucleophilic attack of a second NϵCNH2 spe-
cies on the cyanide carbon atom of the coordinated cyan-
amide, followed by a H-shift, gives N-imine-bonded cyano-
[a] Dipartimento di Chimica, Università Ca’ Foscari Venezia,
Dorsoduro 2137, 30123 Venezia, Italy
[b] Departamento de Química Inorgánica, Universidade de Vigo,
Facultade de Química, Edificio de Ciencias Experimentais,
36310 Vigo (Galicia), Spain
Supporting information for this article is available on the
WWW under http://dx.doi.org/10.1002/ejic.200900639.
5352
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2009, 5352–5357

Cyanoguanidine and Ethylcyanamide Complexes of RuII and OsII
guanidine complex [B]. The linkage isomerisation of this
Complexes 1–4 were isolated as yellow or yellowish-green
ligand gives the final N-nitrile bonded [M]–NϵCN(H)C- solids, stable in air and in solution of polar organic solvents,
(NH2)=NH derivatives 1 and 3.
where they behave as 1:1 electrolytes.[14] Their formulation
is supported by analytical and spectroscopic data (IR and
1H, 31P, 13C NMR) and by X-ray crystal structure determi-
nation of the complex [RuCl{NϵCN(H)C(NH2)=NH}(η6-
p-cymene){PPh(OEt)2}]BPh4 (1b), whose ORTEP diagram
is shown in Figure 1. The structure of the complex consists
of a ruthenium atom η6-coordinated to a p-cymene mole-
cule, one chlorine atom, one diethoxyphenylphosphane
bonded through the phosphorus atom and one N-cyano-
guanidine bonded through the nitrile nitrogen atom in an
η1-fashion.[15] The overall coordination around the metal
consists of a classic “three-legged piano stool” structure.
The geometry of the complex is octahedral and is marked
by near-90° values for angles P1–Ru–Cl1 87.0(1), N1–Ru–
P1 86.2(1), N1–Ru–Cl1 83.5(1)°. The chloride ligand and
N-cyanoguanidine are bonded through a hydrogen bond
(see Table 1 for their metrical parameters), as found also for
the polymeric complex [ZnCl2(C2H4N4)]n.[16]
Scheme 2. [M] = [MCl(η6-p-cymene)(PR3)].
Nucleophilic attack on coordinated nitrile is well docu-
mented[8] for several transition metals, and these precedents
support the proposed path for the metal-mediated dimeri-
sation of the NϵCNH2 to give cyanoguanidine.
We also attempted to prepare cyanamide complexes like
[A] by slow addition of a solution of NϵCNH2 to the start-
ing complexes [MCl2(η6-p-cymene)(PR3)] in a low ratio
(0.8:1), but only cyanoguanidine complexes 1 and 3 were
isolated under all conditions. Nucleophilic attack of free
NϵCNH2 to give cyanoguanidine is probably faster than
the coordination of cyanamide, affording exclusively com-
plexes 1 and 3 as final products.
Ethylcyanamide NϵCNEt2 also reacts with p-cymene
complexes [MCl2(η6-p-cymene)(PR3)] to give the cyan-
amide derivatives [MCl(NϵCNEt2)(η6-p-cymene)(PR3)]-
BPh4 (2 and 4), which were isolated in good yields and
characterised (Scheme 3). Also in this case, the reaction
proceeds by substitution of one chloride by ethylcyanamide
and the formation of cationic complexes 2 and 4.
Figure 1. ORTEP view of the cation of 1b. The ethoxy and phenyl
groups of the phosphonite group are not drawn. The atoms are
drawn at the 30% probability level.
The Ru–P bond and Ru–Cl bonds are 2.287(2) and
2.408(2) Å, respectively, which are in good agreement with
other p-cymene ruthenium complexes.[17] The Ru–N(1)
bond [2.026(6) Å] is slightly shorter than that found in re-
lated nitrile compounds of ruthenium.[18] It is worth noting
that the CCDC database (CSD version 5.30, Feb. 2009 up-
dated)[19] only lists 51 structures of coordination com-
pounds with N-cyanoguanidine and none with ruthenium.
The coordination of N-cyanoguanidine preferentially oc-
curs through nitrile nitrogen N1, as occurs in 1b, and the
Scheme 3. M = Ru (2), Os (4); PR3 = PPh(OEt)2 (b).
Examples of cyanamide and cyanoguanidine complexes N1–C1N bond length [1.138(8) Å] matches well with a tri-
have been reported[1–7] mainly for Mo, Pt and Cu as central ple bond.[15,16,20] The angle N1–C1n–N2 is almost linear
metals, whereas only one example is known for ruthe- [176.7(8)°], and the C1n–N1–Ru angle of only 158.9(6)°
nium[11] and none for osmium. The use of p-cymene frag- may be explained by formation of a hydrogen bond between
ments [MCl(η6-p-cymene)(PR3)] with phosphane or phos- the cyanoguanidine ligand and the coordinated chlorine
phite allowed the synthesis of both new ruthenium com- atom.[20,21] The planarity (rms = 0.0246) and distances
plexes and of the first osmium ones containing cyanoguan- around the C2n carbon atom (Table 1) correspond to large
idine and ethylcyanamide as ligands.
π-electron delocalisation in the ligand.[20]
Eur. J. Inorg. Chem. 2009, 5352–5357
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
5353

G. Albertin, S. Antoniutti, J. Castro
FULL PAPER
Table 1. Selected bond lengths [Å] and angles [°] for 1b.[a]
anion, but also the characteristic signals of the p-cymene
and phosphite or phosphane ligands. One broad signal also
appears between δ = 5 and 4 ppm, which was attributed to
the NH2 or NH protons of the cyanamide ligand. Lowering
the sample temperature caused a change in the spectra, with
the appearance, at –40 °C, of a new broad signal near
3.6 ppm for 1a. However, further lowering of the tempera-
ture did not change the profiles of the spectra in the case
of ruthenium complexes 1 and, even at –90 °C, the expected
third signal, attributable to NH2 or one of the two NH
Bonds
Ru–C1
Ru–C3
Ru–C5
Ru–N1
Ru–Cl1
N1–C1N
N2–C2N
C2N–N2N
2.207(6)
2.257(6)
2.192(6)
2.026(6)
2.4086(18)
1.138(8)
1.337(10)
1.322(9)
Ru–C2
Ru–C4
Ru–C6
Ru–P1
Ru–Ct
N2–C1N
C2N–N1N
2.252(6)
2.232(7)
2.195(6)
2.2876(17)
1.7225(5)
1.330(9)
1.298(10)
Angles
1
groups, did not appear. Instead, at –80 °C, the H NMR
Ct–Ru–N1
Ct–Ru–Cl1
N1–Ru–P1
N1–C1N–N2
129.00(15)
126.55(5)
86.19(15)
176.7(8)
Ct–Ru–P1
129.40(5)
86.99(7)
83.46(17)
158.9(6)
spectrum of osmium complex 3b showed a slightly broad
doublet at δ = 4.34 ppm attributed to the NH2 protons, and
two broad singlets at δ = 5.58 and 4.52 ppm due to the two
NH signals. These attributions are supported by both the
2:1:1 intensity ratio of the signals and the correlations ob-
served in the COSY spectra. The 13C NMR spectra of com-
plexes 1 and 3 fit the proposed formulation, showing the
characteristic signals of the p-cymene and phosphane li-
gands and a singlet at δ = 162.9–162.7 ppm for the CNH2
carbon atom of cyanoguanidine. Instead, the resonance of
the nitrile carbon atom NϵC–N(H) was identified as a
broad singlet at δ = 156.5 ppm only for complex 3b.
P1–Ru–Cl1
N1–Ru–Cl1
C1N–N1–Ru
Dihedral angles
C1–Ct–Ru–N1
C3–Ct–Ru–Cl1 28.6(3)
C5–Ct–Ru–P1
33.1(4)
C2–Ct–Ru–N1 –26.7(4)
C4–Ct–Ru–Cl1 –32.0(3)
C6–Ct–Ru–P1 –29.8(3)
30.5(3)
Hydrogen bond
d(D–H) d(H···A)
1.1(1) 2.42(10)
D–H···A
ЄDHA
d(D···A)
N1n–H1n1···Cl1
156(7)
3.493(9)
[a] Ct represents the centroid of the benzene ring for the p-cymene
ligand.
The IR spectra of the diethylcyanamide complexes
[MCl(NϵCNEt2)(η6-p-cymene)(PR3)]BPh4 (2 and 4) show
a strong band at 2273–2266 cm–1, attributed to νCN of the
The distance from the ruthenium atom to the centroid of
the benzene ring of the cymene ligand is 1.722(2) Å. The
rms value for this plane is 0.019, with maximum deviation
for C1 (isopropyl substituted) and C4 (methyl substituted)
of 0.026(4) and 0.027(4) Å, respectively. The benzene plane
could be considered slightly bent in a boat-shaped confor-
mation, with the substituted carbon atoms facing the metal
atom (Figure 2).
1
nitrile group. The H NMR spectra confirm the presence
of the cyanamide ligand, showing a quartet at δ = 3.09–
2.69 ppm and a triplet at δ = 1.25–0.91 ppm of the ethyl
group of the ligand. At temperature ranges between +20
and –80 °C, the 31P NMR spectra appears as a sharp sing-
let, whereas the 13C{1H} NMR spectra support the pro-
posed formulation, showing the characteristic signals of p-
cymene and the phosphite carbon resonance. A singlet at δ
= 166.6 ppm, attributed to the nitrile carbon resonance, and
two signals at δ = 46.7 and 13.4 ppm of the ethyl group of
NϵCNEt2 also appear in the 13C NMR spectra of 4c, fit-
ting the presence of the cyanamide ligand.
Conclusions
In this paper we report the synthesis of cyanoguanidine
complexes of ruthenium and osmium stabilised by the p-
cymene fragment [MCl(η6-p-cymene)(PR3)] containing
phosphite or phosphane as a supporting ligand. The struc-
tural parameters for ruthenium complex [RuCl{NϵCN(H)-
C(NH2)=NH}(η6-p-cymene){PPh(OEt)2}]BPh4 (1b) were
determined. Ethylcyanamide derivatives [MCl(NϵCNEt2)-
(η6-p-cymene)(PR3)]BPh4 were also prepared and spectro-
scopically characterised.
Figure 2. ORTEP drawn of the cation view along the Ct–Ru vector.
Infrared and NMR spectroscopic data fit the proposed
formulation for cyanamide complexes 1–4. The IR spectra
of cyanoguanidine derivatives 1 and 3 show strong absorp-
tion at 2259–2241 cm–1, attributed to νCN of the nitrile
group, and two or three bands of medium or strong inten-
sity at 3446–3339 cm–1, due to νNH of the amine NH2 and
imine =NH groups of the cyanoguanidine ligand. In the
Experimental Section
General: All synthetic work was carried out under an appropriate
atmosphere (Ar, N2) by using standard Schlenk techniques or a
vacuum/atmosphere dry box. All solvents were dried with appropri-
1630–1627 cm–1 region, the δ
band also occurs. At room
NH2
temperature, the 1H NMR spectra of cyanoguanidine com-
plexes 1 and 3 show not only the multiplet of the BPh4 ate drying agents, degassed on a vacuum line, and distilled into
5354 Eur. J. Inorg. Chem. 2009, 5352–5357
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© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Cyanoguanidine and Ethylcyanamide Complexes of RuII and OsII
vacuum-tight storage flasks. RuCl3·3H2O and (NH4)2OsCl6 were C42H53BClN4O3PRu (840.20): calcd. C 60.04, H 6.36, Cl 4.22, N
purchased from Pressure Chemical Co. (USA) and used as re-
ceived. Phosphites PPh(OEt)2 and PPh2OEt were prepared by the
method of Rabinowitz and Pellon;[22] P(OEt)3 (Aldrich) and PiPr3
(Strem) were used as received. Other reagents were purchased from
commercial sources in the highest available purity and used as re-
ceived. Infrared spectra were recorded with a Perkin–Elmer Spec-
trum One FTIR spectrophotometer. NMR spectra (1H, 31P, 13C)
were obtained with AC200 or Avance 300 Bruker spectrometers at
6.67; found C 60.27, H 6.28, Cl 4.05, N 6.59.
1b: Yield: 256 mg (70%). IR (KBr pellet): ν = 3446 (νNH, s), 3353
˜
(νNH, s), 2245 (νCN, s), 1628 (δNH , s) cm–1. 1H NMR (CD2Cl2,
2
25 °C): δ = 7.58–6.88 (m, 25 H, Ph), 5.64, 5.58, 5.43, 5.24 (d, 4 H,
Ph p-cym), 4.12 (br. s, 4 H, NH, NH2), 4.03, 3.95 (m, 4 H, CH2),
2.55 (m, 1 H, CH), 1.97 (s, 3 H, CH3 p-cym), 1.35, 1.34 (t, 6 H,
CH3 phos), 1.18, 1.16 (d, 6 H, CH3 iPr) ppm. 31P{1H} NMR
(CD2Cl2, 25 °C): δ = 142.0 ppm. 13C{1H} NMR (CD2Cl2, 25 °C):
δ = 165–122 (m, Ph), 162.8 (s, =CNH2), 111.1 (s, C1 p-cym), 102.6
(s, C4), 94.5, 94.4, 86.7 (s, C3), 91.7, 91.6, 88.1 (s, C2), 64.5 (d,
CH2), 31.4 (s, CH), 22.3, 22.2 (s, CH3 iPr), 18.4 (s, CH3 p-cym),
1
temperatures between –80 and +30 °C, unless otherwise noted. H
and 13C spectra are referred to internal tetramethylsilane; 31P{1H}
chemical shifts are reported with respect to 85% H3PO4, with
downfield shifts considered positive. The COSY, HMQC, and
HMBC NMR experiments were performed by using Bruker stan-
dard programs. The SwaN-MR and iNMR software packages[23]
were used to treat NMR spectroscopic data. The conductivity of
10–3 molL–1 solutions of the complexes in CH3NO2 at 25 °C were
measured with a Radiometer CDM 83. Elemental analyses were
determined in the Microanalytical Laboratory of the Dipartimento
di Scienze Farmaceutiche of the University of Padua, Italy.
16.4 (d, CH3 phos) ppm. ΛM
=
52.8 Ω–1 mol–1 cm2.
C46H53BClN4O2PRu (872.25): calcd. C 63.34, H 6.12, Cl 4.06, N
6.42; found C 63.12, H 6.24, Cl 3.89, N 6.27.
1c: Yield: 273 mg (72%). IR (KBr pellet): ν = 3434 (νNH, s), 3339
˜
(νNH, s), 2247 (νCN, s), 1628 (δNH , s) cm–1. 1H NMR (CD2Cl2,
2
25 °C): δ = 7.70–6.83 (m, 30 H, Ph), 5.59, 5.48, 5.24, 5.20 (d, 4 H,
Ph p-cym), 4.10 (br. s, 4 H, NH, NH2), 3.72, 3.63 (m, 2 H, CH2),
2.47 (m, 1 H, CH), 1.93 (m, 3 H, CH3 p-cym), 1.21 (t, 3 H, CH3
phos), 1.11, 1.06 (d, 6 H, CH3 iPr) ppm. 31P{1H} NMR (CD2Cl2,
25 °C): δ = 121.6 ppm. ΛM = 50.9 Ω–1 mol–1 cm2. C50H53BClN4O-
PRu (904.29): calcd. C 66.41, H 5.91, Cl 3.92, N 6.20; found C
66.15, H 6.03, Cl 3.74, N 6.06.
Synthesis of the Complexes: Complexes [MCl2(η6-p-cymene)(PR3)]
[M = Ru, Os; PR3 = P(OEt)3, PPh(OEt)2, PPh2OEt, PiPr3] were
prepared by our method,[24a] as follows: an excess amount of the
appropriate phosphite or phosphane (3.5 mmol) was added to a
[24b,24c]
solution of the dimeric complex [MCl2(η6-p-cymene)]2
1d: Yield: 266 mg (76%). IR (KBr pellet): ν = 3435 (νNH, s), 3357
˜
(0.7 mmol) in CH2Cl2 (10 mL), and the reaction mixture was
stirred at room temperature for 3 h. The solvent was removed under
reduced pressure to give an oil, which was triturated with n-hexane
(10 mL). A yellow solid slowly separated out, which was filtered
and crystallised from dichloromethane and hexane; yield Ն90%.
(νNH, m), 2241 (νCN, s), 1630 (δNH , s) cm–1. 1H NMR (CD2Cl2,
2
25 °C): δ = 7.43–6.90 (m, 20 H, BPh4), 5.59, 5.40 (d, 4 H, Ph p-
cym), 4.06 (br. s, 4 H, NH, NH2), 2.35, 2.33 (m, 4 H, CH), 1.81
(m, 3 H, CH3 p-cym), 1.21 (m, 24 H, CH3 iPr) ppm. 31P{1H} NMR
(CD2Cl2, 25 °C):
δ = 51.6 ppm. ΛM =
55.4 Ω–1 mol–1 cm2.
[RuCl{NCN(H)C(NH2)=NH}(η6-p-cymene)(PR3)]BPh4 (1) [PR3
P(OEt)3 (a), PPh(OEt)2 (b), PPh2OEt (c), PiPr3 (d)]
=
C45H59BClN4PRu (834.28): calcd. C 64.78, H 7.13, Cl 4.25, N 6.72;
found C 64.60, H 7.25, Cl 4.19, N 6.55.
[RuCl(NϵCNEt2)(η6-p-cymene)(PR3)]BPh4 (2) [PR3 = P(OEt)3 (a),
PPh(OEt)2 (b), PPh2OEt (c), PiPr3 (d)]: In a 25-mL, three-necked,
round-bottomed flask was placed the appropriate complex
[MCl2(η6-p-cymene)(PR3)] (0.42 mmol), an excess amount of dieth-
Method 1: In a 25-mL, three-necked, round-bottomed flask was
placed the appropriate complex [MCl2(η6-p-cymene)(PR3)]
(0.42 mmol), an excess amount of cyanamide NϵCNH2
(1.26 mmol, 53 mg), a slight excess amount of NaBPh4 (0.50 mmol,
171 mg), and ethanol (10 mL). The reaction mixture was stirred for
24 h and the yellow-green solid formed was filtered and crystallised
from CH2Cl2 and ethanol.
ylcyanamide NϵCNEt2 (1.26 mmol, 146 µL),
a slight excess
amount of NaBPh4 (0.50 mmol, 171 mg), and ethanol (10 mL).
The reaction mixture was stirred for 24 h and the yellow solid
formed was filtered and crystallised from CH2Cl2 and ethanol.
2a: Yield: 301 mg (84%). IR (KBr pellet): ν = 2273 (νNH, s) cm–1.
Method 2: In a 25-mL, three-necked, round-bottomed flask was
placed the appropriate complex [MCl2(η6-p-cymene)(PR3)]
(0.42 mmol), an excess amount of cyanoguanidine NϵCN(H)-
C(NH2)=NH (0.84 mmol, 71 mg), a slight excess amount of
NaBPh4 (0.50 mmol, 171 mg), and ethanol (10 mL). The reaction
mixture was stirred for 24 h and the yellow-green solid formed was
filtered and crystallised from CH2Cl2 and ethanol.
˜
1H NMR (CD2Cl2, 25 °C): δ = 7.35–6.88 (m, 20 H, BPh4), 5.68,
5.65, 5.60, 5.23 (d, 4 H, Ph p-cym), 4.12 (quint, 6 H, CH2 phos),
3.09 (q, 4 H, CH2 cyanam), 2.67 (m, 1 H, CH), 2.06 (s, 3 H, CH3
p-cym), 1.34 (t, 9 H, CH3 phos), 1.25, 1.23 (d, 6 H, CH3 iPr), 1.24
(t, 6 H, CH3 cyanam) ppm. 31P{1H} NMR (CD2Cl2, 25 °C): δ =
113.8 ppm. ΛM
=
54.3 Ω–1 mol–1 cm2. C45H59BClN2O3PRu
(854.27): calcd. C 63.27, H 6.96, Cl 4.15, N 3.28; found C 63.06,
H 6.88, Cl 4.01, N 3.21.
1a: Yield: 254 mg (72%). IR (KBr pellet): ν = 3435 (νNH, s), 3351
˜
(νNH, s), 2245 (νCN, s) 1627 (δNH , s) cm–1. 1H NMR (CD2Cl2,
2
25 °C): δ = 7.40–6.89 (m, 20 H, BPh4), 5.70, 5.63, 5.55, 5.33 (d, 4
H, Ph p-cym), 4.30 (br. s, 4 H, NH, NH2), 4.07 (quint, 6 H, CH2),
2.67 (m, 1 H, CH), 2.08 (s, 3 H, CH3 p-cym), 1.31 (t, 9 H, CH3
phos), 1.23, 1.21 (d, 6 H, CH3 iPr) ppm. 1H NMR (CD2Cl2,
–40 °C): δ = 7.40–6.88 (m, 20 H, BPh4), 5.67, 5.63, 5.47, 5.26 (d, 4
2b: Yield: 305 mg (82%). IR (KBr pellet): ν = 2260 (νCN, s) cm–1.
˜
1H NMR (CD2Cl2, 25 °C): δ = 7.65–6.89 (m, 25 H, Ph), 5.69, 5.63,
5.56, 5.23 (d, 4 H, Ph p-cym), 4.14, 4.03 (m, 4 H, CH2 phos), 2.75
(m, 4 H, CH2 cyanam), 2.63 (m, 1 H, CH), 2.03 (s, 3 H, CH3 p-
cym), 1.49, 1.40 (t, 6 H, CH3 phos), 1.24, 1.22 (d, 6 H, CH3 iPr),
H, Ph p-cym), 4.73 (br., 2 H, NH), 3.63 (br., 2 H, NH2), 3.98 (quint, 1.03 (t, 6 H, CH3 cyanam) ppm. 31P{1H} NMR (CD2Cl2, 25 °C):
6 H, CH2), 2.59 (m, 1 H, CH), 2.03 (s, 3 H, CH3 p-cym), 1.26 (t, δ = 144.6 ppm. 13C{1H} NMR (CD2Cl2, 25 °C): δ = 165–122 (m,
9 H, CH3 phos), 1.17, 1.13 (d, 6 H, CH3 iPr) ppm. 31P{1H} NMR
(CD2Cl2, 25 °C): δ = 114.2 ppm. 13C{1H} NMR (CD2Cl2, 25 °C):
Ph), 111.2 (s, C1 p-cym), 104.7 (s, C4), 95.6, 95.5, 85.9 (s, C3),
92.32, 92.25, 89.0 (s, C2), 64.8, 64.6 (d, CH2 phos), 46.3 (s, CH2
δ = 165–122 (m, BPh4), 162.7 (s, =CNH2), 110.3 (s, C1 p-cym), cyanam), 31.4 (s, CH), 22.6, 22.1 (s, CH3 iPr), 18.4 (s, CH3 p-cym),
103.2 (s, C4), 94.1, 94.0, 87.1 (s, C3), 92.3, 92.2, 88.81, 88.77 (s, 16.4 (d, CH3 phos), 13.1 (s, CH3 cyanam) ppm. ΛM = 49.5
C2), 63.9 (d, CH2), 31.4 (s, CH), 22.3, 22.0 (s, CH3 iPr), 18.6 (s, Ω–1 mol–1 cm2. C49H59BClN2O2PRu (886.31): calcd. C 66.40, H
CH3 p-cym), 16.3 (d, CH3 phos) ppm. ΛM = 54.6 Ω–1 mol–1 cm2.
6.71, Cl 4.00, N 3.16; found C 66.22, H 6.83, Cl 3.82, N 3.04.
Eur. J. Inorg. Chem. 2009, 5352–5357
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
5355

G. Albertin, S. Antoniutti, J. Castro
FULL PAPER
2c: Yield: 308 mg (80%). IR (KBr pellet): ν = 2269 (νNH, s) cm–1.
63.18, H 5.90, Cl 3.52, N 2.78; found C 62.96, H 5.80, Cl 3.35, N
˜
1H NMR (CD2Cl2, 25 °C): δ = 7.95–6.80 (m, 30 H, Ph), 5.65, 5.57, 2.90.
5.39, 5.30 (d, 4 H, Ph p-cym), 3.81, 3.68 (m, 2 H, CH2 phos), 2.84
X-ray Crystallography: Crystallographic data were collected with a
(q, 4 H, CH2 cyanam), 2.58 (m, 1 H, CH), 1.87 (s, 3 H, CH3 p-
cym), 1.31 (t, 3 H, CH3 phos), 1.22, 1.19 (d, 6 H, CH3 iPr), 1.06
(t, 6 H, CH3 cyanam) ppm. 31P{1H} NMR (CD2Cl2, 25 °C): δ =
122.5 ppm. ΛM = 50.2 Ω–1 mol–1 cm2. C53H59BClN2OPRu (918.36):
calcd. C 69.32, H 6.48, Cl 3.86, N 3.05; found C 69.07, H 6.59, Cl
3.70, N 2.95.
Bruker Smart 1000 CCD diffractometer at CACTI (Universidade
de Vigo) by using graphite monochromated Mo-Kα radiation (λ =
0.71073 Å) and were corrected for Lorentz and polarisation effects.
The software SMART[25] was used for collecting frames of data,
indexing reflections, and the determination of lattice parameters,
SAINT[26] for integration of intensity of reflections and scaling,
and SADABS[27] for empirical absorption correction. The structure
was solved and refined with the Oscail program[28] by Patterson
methods and refined by a full-matrix least-squares based on F2.[29]
Non-hydrogen atoms were refined with anisotropic displacement
parameters. Hydrogen atoms were included in idealised positions
and refined with isotropic displacement parameters except that cor-
responding with the C=N–H group, which was found in the final
density map and refined with isotropic displacement parameters.
The phenyl and ethoxy substituents of the phosphane ligand are
disordered over two positions, with factor occupancy of 56/44%.
Details of crystal data and structural refinement are given in
Table 2. CCDC-739178 (for 1b) contains the supplementary crys-
tallographic data for this paper. These data can be obtained free
of charge from The Cambridge Crystallographic Data Centre via
www.ccdc.cam.ac.uk/data_request/cif.
2d: Yield: 303 mg (85%). IR (KBr pellet): ν = 2258 (νNH, s) cm–1.
˜
1H NMR (CD2Cl2, 25 °C): δ = 7.35–6.87 (m, 20 H, BPh4), 5.75,
5.71, 5.69, 5.38 (d, 4 H, Ph p-cym), 3.11 (q, 4 H, CH2), 2.59 (m, 4
H, CH), 2.01 (s, 3 H, CH3 p-cym), 1.36–1.26 (m, 24 H, CH3 iPr),
1.25 (t, 6 H, CH3 cyanam) ppm. 31P{1H} NMR (CD2Cl2, 25 °C): δ
= 45.9 ppm. ΛM = 52.5 Ω–1 mol–1 cm2. C48H65BClN2PRu (848.35):
calcd. C 67.96, H 7.72, Cl 4.18, N 3.30; found C 68.09, H 7.81, Cl
4.04, N 3.35.
[OsCl{NCN(H)C(NH2)=NH}(η6-p-cymene)(PR3)]BPh4 (3) [PR3
=
PPh(OEt)2 (b), PPh2OEt (c)]: These complexes were prepared ex-
actly like the related ruthenium derivatives 1b and 1c, following
both Method 1 and 2, crystallising the solid obtained from CH2Cl2
and ethanol.
3b: Yield: 319 mg (79%). IR (KBr pellet): ν = 3446 (νNH, s), 3350
˜
(νNH, s), 2246 (νCN, s), 1630 (δNH , s) cm–1. 1H NMR (CD2Cl2,
2
Table 2. Crystal data and structure refinement for 1b.
0 °C): δ = 7.50–6.90 (m, 25 H, Ph), 5.69, 5.61, 5.55, 5.43 (d, 4 H,
Ph p-cym), 5.50 (br. s, 2 H, NH), 4.52 (br. s, 2 H, NH2), 4.02, 3.87
(m, 4 H, CH2), 2.54 (m, 1 H, CH), 2.12 (s, 3 H, CH3 p-cym), 1.31
(m, 6 H, CH3 iPr), 1.18 (t, 6 H, CH3 phos) ppm. 1H NMR
(CD2Cl2, –80 °C): δ = 5.58, 4.52 (br. s, 2 H, NH), 4.34 (br. d, 2 H,
NH2) ppm. 31P{1H} NMR (CD2Cl2, 0 °C): δ = 98.0 ppm. 13C{1H}
NMR (CD2Cl2, 25 °C): δ = 166–121 (m, Ph), 162.9 (s, =CNH2),
156.5 (br. s, NϵC), 102.5 (s, C1 p-cym), 96.2 (s, C4), 85.8, 85. 7,
1b
Empirical formula
Formula weight
Temperature [K]
Wavelength [Å]
Crystal system
Space group
C46H53BClN4O2PRu
872.22
293(2)
0.71073
triclinic
¯
P1
78.6 (s, C3), 84.1, 84.0, 79.90, 79.87 (s, C2), 64.0 (d, CH2), 31.1 (s, a [Å]
9.9275(16)
13.978(2)
16.662(3)
98.675(3)
103.182(4)
93.388(3)
2214.9(6)
2
b [Å]
c [Å]
α [°]
β [°]
CH), 22.6, 22.5 (s, CH3 iPr), 18.1 (s, CH3 p-cym), 16.3 (d, CH3
phos) ppm. ΛM
=
51.7 Ω–1 mol–1 cm2. C46H53BClN4O2OsP
(961.41): calcd. C 57.47, H 5.56, Cl 3.69, N 5.83; found C 57.23,
H 5.69, Cl 3.84, N 5.79.
γ [°]
Volume [Å3]
Z
3c: Yield: 321 mg (77%). IR (KBr pellet): ν = 3451 (νNH, s), 3356
˜
(νNH, s), 2259 (νCN, s), 1629 (δNH , s) cm–1. 1H NMR (CD2Cl2,
2
Dcalcd. [Mgm–3]
1.308
0.491
908
25 °C): δ = 7.60–6.86 (m, 30 H, Ph), 5.74, 5.63, 5.53, 5.50 (d, 4 H,
Ph p-cym), 4.17 (br., 4 H, NH, NH2), 3.78, 3.65 (m, 2 H, CH2),
2.53 (m, 1 H, CH), 2.20 (s, 3 H, CH3 p-cym), 1.20, 1.15 (d, 6 H,
CH3 iPr), 1.19 (t, 3 H, CH3 phos) ppm. 31P{1H} NMR (CD2Cl2,
µ [mm–1]
F(000)
Crystal size [mm]
θ range for data collection [°]
Index ranges
0.47ϫ0.42ϫ0.14
1.48 to 28.07
–12 Յ h Յ 13
–18 Յ k Յ 18
–21 Յ l Յ 16
14414
10085 [R(int) = 0.0461]
4279
0.939
semiempirical from equivalents
1.000 and 0.772
full-matrix least-squares on F2
10085/0/571
0.970
R1 = 0.0654 wR2 = 0.1483
R1 = 0.1691 wR2 = 0.2009
0.833/–1.307
25 °C):
δ
=
81.1 ppm. ΛM
=
53.8 Ω–1 mol–1 cm2.
C50H53BClN4OOsP (993.45): calcd. C 60.45, H 5.38, Cl 3.57, N
5.64; found C 60.61, H 5.24, Cl 3.26, N 5.51.
Reflections collected
[OsCl(NϵCNEt2)(η6-p-cymene)(PPh2OEt)]BPh4 (4c): This com-
plex was prepared exactly like the related ruthenium derivative 2c,
Independent reflections
Reflections observed (Ͼ2σ)
Data completeness
Absorption correction
Max. and min. transmission
Refinement method
crystallising the solid obtained from CH2Cl2 and ethanol. Yield:
1
355 mg (84%). IR (KBr pellet): ν = 2266 (νCN, s) cm–1. H NMR
˜
(CD2Cl2, 25 °C): δ = 7.80–6.86 (m, 30 H, Ph), 5.62, 5.51, 5.48, 5.42
(d, 4 H, Ph p-cym), 2.93, 2.83 (quint, 2 H, CH2 phos), 2.70, 2.69
(d, 4 H, CH2 cyanam), 2.26 (m, 1 H, CH), 1.96 (s, 3 H, CH3 p-
cym), 1.26, 1.24 (d, 6 H, CH3 iPr), 0.96 (t, 3 H, CH3 phos), 0.91
(t, 6 H, CH3 cyanam) ppm. 31P{1H} NMR (CD2Cl2, 25 °C): δ =
88.2 ppm. 13C{1H} NMR (CD2Cl2, 25 °C): δ = 166.6 (s, NϵC),
165–122 (m, Ph), 101.4 (s, C1 p-cym), 96.6 (s, C4), 87.0, 86.6, 85.0,
84.8 (s, C3), 84.5, 84.0, 80.1, 78.7 (s, C2), 46.7 (s, CH2 cyanam),
43.7 (d, CH2 phos), 32.3 (s, CH), 22.6, 22.4 (s, CH3 iPr), 18.4 (s,
Data/restraints/parameters
Goodness-of-fit on F2
Final R indices [IϾ2σ(I)]
R indices (all data)
Largest diff. peak/hole [eÅ–3]
Supporting Information (see footnote on the first page of this arti-
CH3 p-cym), 16.2 (d, CH3 phos), 13.4 (s, CH3 cyanam) ppm. ΛM cle): Additional perspective views of 1b and the complete list of
= 51.1 Ω–1 mol–1 cm2. C53H59BClN2OOsP (1007.52): calcd. C
bond lengths and angles for 1b.
5356
www.eurjic.org
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2009, 5352–5357

Cyanoguanidine and Ethylcyanamide Complexes of RuII and OsII
A. Bacchi, F. De Marchi, G. Pelizzi, Inorg. Chem. 2005, 44,
8947–8954.
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Received: July 7, 2009
Published Online: October 23, 2009
Eur. J. Inorg. Chem. 2009, 5352–5357
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
5357