Ruthenium(II) trerdentate CNN complexes: Superlative catalysts for the hydrogen-transfer reduction of ketones by reversible insertion of a carbonyl group into the Ru-H bond

Article abstract of DOI:10.1002/anie.200502118

(Chemical Equation Presented) Very low loading and short reaction times are characteristic features of the quantitative reduction of different ketones using 2-propanol and terdentate [RuX(CNN)-(dppb)] (X = H, Cl (see structure); dppb = Ph₂P(CH₂)₄PPh₂) complexes prepared from 6-(4′-methylphenyl)-2-pyridyl-methylamine. The reduction apparently takes place by reversible insertion of the substrate into the Ru-H bond, thus leading to a Ru^II alkoxide.

Full text of DOI:10.1002/anie.200502118

Communications
Homogeneous Catalysis
complex
[RuCl(CO)(CP)(ampy)]
(CP = (2-CH2-6-
MeC6H3)PPh2), with turnover frequencies (TOF values) up
to 6.3 ” 104 hÀ1, whereas the derivatives cis-[RuCl2(PP)-
(ampy)] (PP = diphosphane) lead to TOF values up to 4.0 ”
105 hÀ1 and ee values up to 94% by using chiral diphos-
phanes.[5] Since it is well known that 2-phenylpyridine readily
gives access to orthometalated CN ruthenium complexes,[6]
we decided to investigate the coordination chemistry of the
related 6-(4’-methylphenyl)-2-pyridylmethylamine with the
aim of obtaining terdentate CNN complexes. We report
herein on novel complexes of formula [RuX(CNN)(dppb)]
(X = Cl, H; dppb = Ph2P(CH2)4PPh2), which are remarkably
active catalysts for transfer hydrogenation that afford
TOF values up to 2.5 ” 106 hÀ1 with very low loading of
catalysts (0.005–0.001mol%) compared to the most active
systems reported.[2f,7] Evidence is provided that the reduction
of the ketone proceeds through the formation of a RuII–
alkoxide complex by insertion of the carbonyl group of the
DOI: 10.1002/anie.200502118
Ruthenium(ii) Terdentate CNN Complexes:
Superlative Catalysts for the Hydrogen-Transfer
Reduction of Ketones by Reversible Insertion of a
À
Carbonyl Group into the Ru H Bond**
Walter Baratta,* Giorgio Chelucci, Serafino Gladiali,
Katia Siega, Micaela Toniutti, Matteo Zanette,
Ennio Zangrando, and Pierluigi Rigo
Dedicated to Professor Fausto Calderazzo
on the occasion of his 75th birthday
Pincer ECE (E = N, P) transition-metal complexes, in which
the terdentate ligands contain two stable five-membered
cyclometalated rings, have reached a high level of sophisti-
cation and appear extremely attractive for both catalytic and
stoichiometric reactions.[1] The great interest in pincer ligands
arises from the high level of control over the reactivity and the
stereochemistry that they impose around the metal center as a
result of their electronic properties and geometric restrictions.
These factors afford highly selective trans-
À
substrate into the Ru H bond of a ruthenium(ii) hydride
formed as an intermediate from the chloride complex 1.
Treatment of [RuCl2(PPh3)(dppb)] with an equimolar
amount of 6-(4’-methylphenyl)-2-pyridylmethylamine in 2-
propanol at reflux in the presence of NEt3 affords the
thermally stable orthometalated ruthenium(ii) complex 1[8] in
high yield [Eq. (1)].
formations and lead to some unique spe-
cies of relevance for the investigation of
elementary processes.[2] In spite of the
great attention afforded to ruthenium for
its versatility in catalysis,[3] no examples of
terdentate ruthenium CNN catalysts have
been reported thus far. It is worth noting
that CNN complexes are expected to have
significantly different reactivity compared to the NCN
analogues, mainly because of the different geometrical
disposition of the s-donor carbon atom.
Recently, we have shown that 2-(aminomethyl)pyridine
(ampy) shows a high ligand acceleration effect in transfer
hydrogenation[4] catalyzed by ruthenium(ii) complexes with
phosphane ligands. Thus, complete reduction of many ketones
in 2-propanol is quickly achieved with the cyclometalated
The signals for the diastereotopic NCH2 protons in the
1H NMR spectrum are at d = 4.12 and 3.72 ppm with
2J(H,H) = 15.5 Hz. The doublet at d = 52.5 ppm with a
3J(C,P) = 2.7 Hz in the 13C NMR spectrum corresponds to
the CH2N group which is shifted downfield relative to the free
ligand (d = 48.2 ppm), thus indicating coordination of the
NH2 group to the metal center. Finally, the signal for the
orthometalated carbon atom appears as a doublet of doublets
at d = 181.8 ppm with 2J(C,P) = 16.3 and 7.8 Hz, which is
strongly shifted downfield[6a,9] relative to the free ligand (Dd =
54.8), thus allowing the former formulation to be established
unambiguously in solution. The X-ray analysis carried out on
a single crystal of 1 shows a severely distorted octahedral
environment around the ruthenium center comprising the
orthometalated terdentate pyridine ligand, the diphosphane,
and a chloride ligand (Figure 1).[10]
[*] Prof. W. Baratta, Dr. K. Siega, Dr. M. Toniutti, Dr. M. Zanette,
Prof. P. Rigo
Dipartimento di Scienze e Tecnologie Chimiche
Università di Udine
Via Cotonificio 108, 33100 Udine (Italy)
Fax: (+39)0432-558-803
E-mail: inorg@dstc.uniud.it
Dr. G. Chelucci, Prof. S. Gladiali
Dipartimento di Chimica
Università di Sassari
The two N1-Ru-C1 and N1-Ru-N2 bond angles in the five-
membered rings are rather small, (80.32(13) and 76.45(12)8,
respectively) because of the geometrical constrains of the
Via Vienna 2, 07100 Sassari (Italy)
À
terdentate ligand. The Ru N2 bond length of 2.246(3) Š is
Prof. E. Zangrando
Dipartimento di Scienze Chimiche
Università di Trieste
À
significantly longer than the Ru N1bond (2.046(3) Š)
because of the trans influence exerted by the aryl group.
The terdentate ligand presents coplanar atoms with the
exception of the CH2NH2 group, the carbon and amino
nitrogen atoms of which are displaced by À0.13 and 0.53 Š,
Via L. Giorgieri 1, 34127 Trieste (Italy)
[**] This work was supported by the Ministero della Ricerca Scientifica e
Tecnologica (MURST).
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Chemie
shows low activity for acetophenone (Ru 0.005 mol%, NaOH
2 mol%, 7% conversion after 1h) under identical exper-
imental conditions, thus suggesting that the high performance
of 1 is in someway related to an assistance of the NH group in
the catalytic cycle. Interestingly, complete reduction (98%) is
achieved in 1h with a substrate/ 1 ratio of 100000:1 (TOF =
5.2 ” 105 hÀ1), and experiments at lower catalyst loading
(0.0005 mol%) led to a turnover number (TON) of 1.7 ”
105. These results are of particular relevance for large-scale
synthesis since hydrogen-transfer catalysts are usually used in
the range of 1–0.01 mol% as a consequence of their easy
deactivation, with TOF values lower than 105 hÀ1. As shown in
Table 1, alkyl–aryl, dialkyl (cyclic and linear), and diaryl
ketones are rapidly (minutes), quantitatively, and chemo-
selectively reduced to alcohols with TOF values in the range
5.0 ” 105 to 2.5 ” 106 hÀ1 with 0.005 mol% of 1. The high
performance of 1 means that this protocol allows the
preparation of alcohols on a gram scale using very low
amounts of catalyst.[12]
Figure 1. ORTEP representation of complex 1. Thermal ellipsoids are
at 40% probability, the labeling scheme of the phenyl carbon atoms is
omitted for clarity. Selected coordination bond lengths [Š] and angles
[8]: Ru-C1 2.057(4), Ru-N1 2.046(3), Ru-N2 2.246(3), Ru-P1 2.252(1),
Ru-P2 2.287(1), Ru-Cl1 2.495(1); N1-Ru-C1 80.32(13), N1-Ru-N2
76.45(12), N2-Ru-P1 102.59(8), N1-Ru-P2 173.00(8), C1-Ru-P2
103.60(10), N2-Ru-P2 98.74(8), P1-Ru-P2 94.85(4), P1-Ru-Cl1
173.29(3), C1-Ru-N2 155.40(12), C1-Ru-P1 85.78(9), N1-Ru-P1
91.20(8).
It is generally accepted that the role of the base in
ruthenium-catalyzed hydrogen-transfer reactions is to gener-
ate hydrides, which are the catalytic active species.[13] In
agreement with this, we have found that reaction of 1 with
sodium isopropoxide in a 2-propanol/toluene solution affords
the orange hydride complex 2[14] through elimination of
acetone on evaporation of the medium [Eq. (3)].
respectively, from the mean
plane. Related terdentate PtII
and PdII complexes obtained
from 6-phenyl-2-(2-aminoiso-
propyl)pyridine have recently
been reported.[11]
Complex 1 has been found to
display an exceptionally high
catalytic activity in the reduction
of a large number of ketones (0.1m) with 2-propanol as the
hydrogen donor and in the presence of NaOH (2 mol%)
[Eq. (2)].
The 31P NMR spectrum of 2 displays two doublets at d =
65.7 and 34.6 ppm with a relatively small 2J(P,P) coupling
constant of 17.2 Hz. The resonance of the hydride in the
1H NMR spectrum appears as a doublet of doublets at d =
2
À5.58 ppm with J(H,P) = 89.1and 26.4 Hz, which is consis-
tent with the presence of trans and cis phosphorus atoms.[15]
An IR band of medium intensity appears at n˜ = 1743 cmÀ1
À
corresponding to the Ru H species and this low-frequency
shift is in agreement with the strong trans influence of the
phosphane ligand.[16] It is noteworthy that addition of hydride
2 (1mol%) to acetophenone and 2-propanol (1:1molar ratio)
in C6D6 leads, at room temperature and within a few minutes,
to an equilibrium mixture in which 1-phenylethanol and
acetone are formed. Hydride 2 is a catalyst of impressive
activity in 2-propanol at reflux which leads to complete
conversion of acetophenone in a few minutes with TOF val-
ues ranging from 4.8 ” 104 hÀ1 (2 0.01mol%, in the absence of
any additional base) to 8.0 ” 105 hÀ1 (in the presence of a
tenfold excess of NaOiPr).
Acetophenone is quantitatively reduced to 1-phenyletha-
nol in five minutes using a substrate/1 ratio of 20000:1with a
remarkably high TOF value of 1.1 ” 106 hÀ1 at 50% conver-
sion (Table 1). Subsequent addition of further amounts of the
ketone (two times) results in complete reduction, thus
suggesting that the stability of the complex results from the
rigid framework built up by the association of the robust
terdentate ligand with the chelating diphosphane, and con-
sequently catalyst deactivation is significantly retarded.
Complex 1 can also be generated in situ from [RuCl2-
(PPh3)(dppb)] and the functionalized pyridine ligand (1:2
molar ratio) in 2-propanol and it shows the same activity as
the isolated compound. In contrast, the in situ prepared
analogue of 1 bearing N(CH3)2 instead of the NH2 group
Complex 2 reacts promptly with an equimolar amount of
benzophenone in C6D6 at 208C to give the alkoxide–amine
complex 3[17] through insertion of the ketone into the Ru H
bond (Scheme 1).
À
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Communications
Scheme 1.
which is in agreement with other
metal alkoxides.[18] NMR spectro-
scopic studies show that heating a
solution of 3 in [D8]toluene above
708C results in reversible genera-
tion of both the ketone and the
hydride 2.
The alkoxide 3 is sensitive to
protic compounds and the corre-
sponding alcohol adducts are
observed in the presence of alco-
hols.[19] Addition of benzhydrol
(2 equivalents) to 3 results in the
Table 1: Catalytic reduction of ketones (0.1m) with 1 (0.005 mol%) and NaOH (2 mol%) in 2-propanol
at 828C.
Ketone
Alcohol
Conversion
[%][a]
TOF [hÀ1 [b]
]
min
98
98
5
1.1”106
1.9”106
2
2.5”106
1.2”106
formation of the species
4
99
99
1
5
(31P NMR: d = 55.0 and 42.8 ppm,
with 2J(P,P) = 34.2 Hz), according
to the equilibrium shown in
Scheme 1( 3/4 ca. 1.5:1). Heating
the solution results in an increase
of 3, and coalescence of the signals
for 3 and 4 is observed at about
608C. Elimination of benzhydrol
has been observed with more
acidic compounds such as water or
carboxylic acids.[20] It is worth
noting that a 31P NMR spectroscop-
ic study of the reaction of 1 with
NaiOPr in 2-propanol/toluene to
give the hydride 2 shows two dou-
blets at d = 54.3 and 44.6 ppm, with
2J(P,P) = 34.2 Hz. These values are
close to those of 4, thus suggesting
the formation of a similar adduct
between the ruthenium isopropox-
ide and 2-propanol. A variable tem-
perature NMR study shows that
97
99
97
2
10
5
1.5”106
5.0”105
7.0”105
98
10
5.3”105
1
[a] The conversion was determined by GC or H NMR analysis. [b] Turnover frequency (mol of ketone
converted into alcohol per mol of catalyst per hour) at 50% conversion.
The 31P NMR spectrum of 3 shows two doublets at d =
57.0 and 37.3 ppm with 2J(P,P) = 34.2 Hz; this coupling
constant is slightly smaller than that of 1 (2J(P,P) = 38.3 Hz).
The proton signal for the RuOCH moiety appears as a
heating this solution above 408C leads to an equilibrium
reaction between the Ru-isopropoxide and the hydride 2,
whose concentration can also be increased by elimination of
acetone through evaporation (in agreement with the reaction
of benzophenone shown in Scheme 1).
4
doublet at d = 4.80 ppm (08C in [D8]toluene) with J(H,P) =
While the insertion of unsaturated compounds into the
3.7 Hz, whereas one broad resonance shifted downfield to d =
5.30 ppm arises from one proton of the amine group, which
may suggest an NH···O hydrogen bond interaction that
stabilizes the alkoxide 3. The 13C NMR peak of the OCH
moiety in C6D6 appears at d = 80.1ppm and it is shifted
downfield relative to free benzhydrol (d = 76.1ppm), a result
À
Ru H bond has been thoroughly studied, examples of the
formation of Ru–alkoxides by reaction of ketones are rare
and restricted to ketoesters or to substrates containing an
additional electron-withdrawing group.[21] The reverse reac-
tion, that is, b-hydrogen elimination,[22] provides one of the
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Angew. Chem. Int. Ed. 2005, 44, 6214 –6219

Angewandte
Chemie
most practical routes to metal hydrides. The reversibility of
this process, however, has been clearly established only for
[Re3(m-OiPr)3(OiPr)6],[23a] although spectroscopic evidence
has been collected at low temperature for [OsCl-
(OCH(CD3)2)(CO)(PiPr3)2].[23b] Recently, the NH-assisted
catalysts in transfer hydrogenation involving 2-propanol to
afford quantitative reduction of different ketones with very
low loading and in a short time. Reduction of ketones
apparently takes place by insertion of the substrate into the
II
À
Ru H bond, thus leading to a Ru alkoxide. The reversibility
À
reversible insertion of CO2 into the Ru H bond to give the
of this step has been observed in the case of the stoichiometric
reaction of complex 2 with benzophenone. This fact provides
strong evidence that a Ru alkoxide derivative is most
probably an intermediate in the formation of the hydride 2,
the putative active catalyst, from the relevant chloride 1. As
the structure of the terdentate pyridine ligand is well suited
for a modular synthetic approach, which allows for a fine
tuning of the stereoelectronic properties of the CNN com-
plexes, this new class of ruthenium derivatives holds the
promise for a broad application in organometallic chemistry
and in homogeneous asymmetric catalysis.
formate–amine species has been reported by Koike and
Ikariya.[24] Interestingly, spectroscopic evidence of ruthe-
nium–alkoxide–amine species has been obtained starting
from ruthenium–amide complexes and alcohols.[25]
The results of the study on the stoichiometric reactions of
the CNN complexes, together with the influence of the
alkoxide concentration on the catalytic activity of the hydride
2, provide strong support to the formation of a discrete
intermediate Ru–alkoxide species in the course of the
catalytic transfer hydrogenation of ketones. As this fact
cannot be explained by the concerted outer-sphere mecha-
nism first proposed by Noyori and co-workers for ruthenium
catalysts containing ligands with NH donor groups (metal– Experimental Section
ligand bifunctional catalysis),[4b,26] an alternative mechanism
for this process may be envisioned as follows. The catalytically
active Ru–isopropoxide species, which is formed from 1 and
sodium isopropoxide, equilibrates with hydride 2. Insertion of
1: [RuCl2(PPh3)(dppb)] (1.17 g, 1.36 mmol) was added to a solution of
2-propanol (15 mL) containing 6-(4’-methylphenyl)-2-pyridylmethyl-
amine (300 mg, 1.51 mmol) and NEt3 (1.9 mL, 13.6 mmol). The
mixture was refluxed for 2 h and the yellow precipitate was filtered,
washed with methanol, and dried under reduced pressure. Yield:
810 mg (78%).
À
the ketone into the Ru H bond of 2 provides a new
ruthenium alkoxide, such as 3. The latter, on exchange with
2-propanol, delivers the reaction product and regenerates the
Ru–isopropoxide complex, thus closing the catalytic cycle.
Although the classical ketone insertion into the metal-hydride
bond and the b-hydrogen elimination pathways,[4e,27] involving
a cis vacant site (that is, through dissociation of the NH2
moiety), cannot be ruled out, it is more likely that both
elementary steps occur through hydrogen-bond assistance of
the NH2 group, without NH proton transfer. For example, the
2: Compound 1 (516 mg, 0.679 mmol) was suspended in toluene
(10 mL) and a solution of NaOiPr (0.1m, 1.00 mmol) in 2-propanol
(10 mL) was added. The solution was concentrated after 1 h at 608C,
stirred at room temperature, and after addition of toluene, filtered
over celite. The filtrate was evaporated and the solid was precipitate
from toluene and filtered, to afford a bright orange product which was
dried under reduced pressure. Yield: 395 mg (80%).
3: Benzophenone (45 mg, 0.247 mmol) was added to a suspension
of 2 (160 mg, 0.220 mmol) in toluene (2 mL), and the solution was
stirred for 15 min. The solution was then concentrated and pentane
added. This afforded a dark yellow precipitate which was filtered and
dried under reduced pressure. Yield: 140 mg (70%).
=
development of an NH···O C interaction between the amine
and the incoming ketone may at the same time activate the
substrate towards the nucleophilic attack and provide the
ketone with the correct orientation for the hydride transfer to
be feasible. The resulting alkoxide anion might then migrate
from the hydrogen to the metal center, possibly through a
three-centered reaction mechanism, to afford the Ru–alk-
oxide intermediate. Thus, the formation of the Ru hydride
from the Ru alkoxide may occur through the reverse pathway.
Strong hydrogen bonding between the substrate, catalyst, and
solvent probably plays a key role in the overall process.
Theoretical studies on the mechanism of the transfer hydro-
genation with Ru/NH catalysts show that ruthenium meth-
oxide–amine complexes are the most stable species along the
reaction pathways.[26b,28]
Finally, it is worth noting that our approach can be easily
extended to the high-speed enantioselective transfer hydro-
genation. Thus, when [RuCl2(PPh3)(dppb)] is treated with the
chiral derivative of 6-phenyl-2-pyridylmethylamine with a tBu
group on the CHNH2 arm (R enantiomer), rapid conversion
of o-methoxyacetophenone into (S)-o-methoxy-a-phenyl-
ethanol is observed (Ru 0.05 mol%, TOF = 6.0 ” 105 hÀ1,
ee = 87%), in agreement with the non-hemilabile behavior
of the NH2 function of the CNN ligand.
Typical procedure for the catalytic hydrogen-transfer reaction:
Complex 1 (3.0 mg, 4.0 mmol) was dissolved in 2-propanol (8 mL).
The ketone (2 mmol) was dissolved in 2-propanol (19 mL) and the
solution heated to reflux under argon. Addition of NaOH (0.1m,
400 mL) and the solution containing the catalyst 1 (200 mL) resulted
in the reduction of the ketone starting immediately. The yield was
determined by GC or NMR analysis (ketone:1:NaOH = 20000:1:400;
ketone 0.1m).
Received: June 17, 2005
Published online: September 1, 2005
Keywords: homogeneous catalysis · hydride · hydrogenation ·
.
orthometalation · ruthenium
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Angew. Chem. Int. Ed. 2005, 44, 6214 –6219ꢀ 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Communications
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[14] 2: 1H NMR (200.1MHz, C 6D6, 208C, TMS): d = 8.55–5.90 (m,
26H; ArH), 3.10–0.90 (m, 12H; CH2 and NH2), 2.30 (s, 3H;
CH3), À5.58 ppm (dd, J(H,P) = 89.1, 26.4 Hz, 1H; RuH);
13C{1H} NMR (50.3 MHz, C6D6, 458C, TMS): d = 189.1 (s;
CRu), 163.0 (s; NCC), 154.8 (s; NCCH2), 149.2–113.2 (m; Ar),
52.1(d, J(C,P) = 2.8 Hz; CH2N), 32.5 (d, J(C,P) = 13.8 Hz;
CH2P), 30.0 (d, J(C,P) = 21.3 Hz; CH2P), 27.0 (s; CH2), 22.8 (s;
CH2), 22.0 ppm (s, CH3); 31P{1H} NMR (81.0 MHz, C6D6, 208C,
H3PO4): d = 65.7 (d, J(P,P) = 17.2 Hz), 34.6 ppm (d, J(P,P) =
17.2 Hz); IR (Nujol): n˜ = 1743 cmÀ1 (br, RuH); elemental
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[17] 3: 1H NMR (200.1MHz, C 6D6, 208C, TMS): d = 8.40–5.80 (m,
35H; ArH), 5.58 (d, J(H,H) = 7.2 Hz, 1H; ArH), 5.35 (brs, 1H;
NH2), 4.86 (s, 1H; OCH), 3.20–2.60 (m, 5H), 2.25 (s, 3H; CH3),
2.10–0.9 ppm (m, 6H); 13C{1H} NMR (50.3 MHz, C6D6, 208C,
TMS): d = 187.6 (s; CRu), 163.8 (s; NCC), 157.4 (s; NCCH2),
155.7–112.4 (m; Ar), 80.1 (s, OCH), 52.0 (s; CH2N), 31.6 (d,
J(C,P) = 29.2 Hz; CH2P), 30.9 (d, J(C,P) = 26.7 Hz; CH2P), 27.0
(s; CH2), 22.6 (s; CH2), 22.1ppm (s, CH 3); 31P{1H} NMR
(81.0 MHz, C6D6, 208C, H3PO4): d = 57.0 (d, J(P,P) = 34.2 Hz),
37.3 ppm (d, J(P,P) = 34.2 Hz); elemental analysis (%) calcd for
C54H52N2OP2Ru: C 71.43, H 5.77, N 3.09; found: C 70.51, H 5.39,
N 2.81.
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[8] 1: 1H NMR (200.1MHz, CD 2Cl2, 208C, TMS): d = 8.10–6.57 (m,
24H; ArH), 6.00 (t, J(H,H) = 8.1Hz, 2H; m-Ph), 4.12 (dd,
J(H,H) = 15.5, 4.4 Hz, 1H; CH2N), 3.72 (td, J(H,H) = 15.5,
4.1Hz, 1H; CH 2N), 3.41(m, 1H; NH 2), 3.05 (m, 2H; CH2P),
2.46–0.90 (m, 7H; NH and CH2), 2.23 ppm (s, 3H; CH3); 13C{1H}
NMR (50.3 MHz, CD2Cl2, 208C, TMS): d = 181.8 (dd, J(C,P) =
16.3, 7.8 Hz; CRu), 163.2 (s; NCC), 155.9 (s; NCCH2), 149.2–
116.0 (m; Ar), 52.5 (d, J(C,P) = 2.7 Hz; CH2N), 33.4 (d, J(C,P) =
26.3 Hz; CH2P), 30.7 (d, J(C,P) = 31.6 Hz; CH2P), 26.8 (s; CH2),
22.1(s; CH 2), 21.8 ppm (s, CH3); 31P{1H} NMR (81.0 MHz,
CD2Cl2, 208C, H3PO4): d = 57.3 (d, J(P,P) = 38.3 Hz), 42.6 ppm
(d, J(P,P) = 38.3 Hz); elemental analysis (%) calcd for
C41H41N2ClP2Ru: C 64.77, H 5.44, N 3.68; found: C 64.36, H
5.52, N 3.70.
[9] T. Koizumi, T. Tomon, K. Tanaka, Organometallics 2003, 22, 970,
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[10] Crystal structure analysis of 1·2C6H6, C53H53N2ClP2Ru, Mr =
¯
916.43, triclinic, space group P1, a = 11.547(3), b = 13.307(3),
c = 16.400(4) Š, a = 84.38(3), b = 74.29(3), g = 69.38(2)8, V=
2270.4(10) Š3, Z = 2, 1calcd = 1.341 gcmÀ3, m = 4.285 mmÀ1, F-
(000) = 952, q = 3.55–64.828. Final R1 = 0.0487, wR2 = 0.1262,
S = 1.087 for 533 parameters and 6542 reflections (of which
6251with I > 2s(I)), max positive and negative peaks in DF map
0.547 and À0.689 eŠÀ3. Data were collected at 160(2) K on a
Nonius FR590 rotating anode (CuKa radiation, l = 1.54178 Š)
equipped with KappaCCD detector. CCDC-265691contains the
supplementary crystallographic data for this paper. These data
can be obtained free of charge from the Cambridge Crystallo-
graphic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
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zophenone in 2-propanol (NaOH 2 mol%) after 2 h at reflux
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ꢀ 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Angewandte
Chemie
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