Synthesis, crystal structure, and reactivity of (5,10,15,20-tetraphenylporphyrinato)ruthenium(II) (diethoxycarbonyl)carbene methanol

Article abstract of DOI:10.1021/om970790u

The new (porphyrin)ruthenium(II) carbene complex 1 has been prepared by treating (TPP)-Ru(CO)[EtOH] with excess diethyl diazomalonate. The good stability of this complex allowed us to determine its structure by single-crystal X-ray diffraction. The reacti

Full text of DOI:10.1021/om970790u

Organometallics 1998, 17, 565-569
565
Syn th esis, Cr ysta l Str u ctu r e, a n d Rea ctivity of
5,10,15,20-Tetr a p h en ylp or p h yr in a to)r u th en iu m (II)
(
(
Dieth oxyca r bon yl)ca r ben e Meth a n ol
†
†
‡
,†
Erwan Galardon, Paul Le Maux, Loic Toupet, and G e´ rard Simonneaux*
Laboratoire de Chimie Organom e´ tallique et Biologique, UMR 6509, and Groupe de Physique
Cristalline, UA CNRS 040804, Universit e´ de Rennes 1, Campus de Beaulieu,
3
5042 Rennes Cedex, France
Received September 8, 1997
The new (porphyrin)ruthenium(II) carbene complex 1 has been prepared by treating (TPP)-
Ru(CO)[EtOH] with excess diethyl diazomalonate. The good stability of this complex allowed
us to determine its structure by single-crystal X-ray diffraction. The reactivity of 1 toward
various axial ligands (CO, pyridine, triphenylphosphine) is also discussed, as well as its
ability, from ethyl diazoacetate, to catalyze the coupling formation of olefins and the
cyclopropanation of styrene.
In tr od u ction
and co-workers.9 Catalytic asymmetric cyclopropana-
tion of styrene with aryl diazoacetates with these
complexes resulted in formation of anti 2-phenylcyclo-
propane carboxylates with high enantioselectivity.9b As
part of our continuing effort to develop ruthenium
porphyrin chemistry, we report now the synthesis,
crystal structure, and reactivity of an air-stable (5,10,-
Recent growth in the area of transition-metal por-
phyrin chemistry has, in part, been driven by the
increased interest associated with metal-catalyzed cy-
1
,2
clopropanation. Examples involving rhodium,
os-
mium, and iron4 porphyrins as catalysts have been
previously reported. Rhodium catalysts produce syn-
thetically useful excesses of cis cyclopropyl esters using
ethyl diazoacetate as the carbene source, whereas under
the same conditions, osmium and iron catalysts mainly
provide the trans product. Catalytic production of
olefins from ethyl diazoacetate has been recently re-
3
1
5,20-tetraphenylporphyrinato)ruthenium (diethoxycar-
bonyl)carbene complex. To our knowledge, this is the
first (porphyrin)ruthenium(II) carbene complex that has
been characterized by single-crystal X-ray diffraction
analysis.
5
6
ported with osmium and ruthenium porphyrins. De-
spite the periodic relationship of ruthenium to iron and
osmium and the syntheses of different carbene com-
plexes of ruthenium porphyrins, nicely developed by
Resu lts a n d Discu ssion
Syn th esis. Four different methods have been devel-
oped for the preparation of (porphyrin)ruthenium car-
bene complexes: (i) insertion of Ru3(CO)12 into the C-N
6
,7
Collman et al., it has only been very recently that
cyclopropanation and ethyl diazoacetate insertion into
heteroatom bond reactions have been observed using
ruthenium porphyrins as catalysts.8 Recently, a set of
stable chiral ruthenium bis(oxazolinyl)pyridine carbene
complexes were also isolated and studied by Nishiyama
1
0
7a
bonds of N,N′-bridged porphyrins, (ii) direct cleavage
of ruthenium porphyrin dimers
1
1,12
with diazo deriva-
tives, (iii) treatment of zerovalent ruthenium porphyrin
7
b
dianions with geminal dihalides, and (iv) direct addi-
6
tion of diazo derivatives to monomeric 14-electron
1
3
ruthenium porphyrins. All these syntheses are lengthy
and quite tedious. We recently discovered a simple
method to ligate carbenes directly onto ruthenium
*
To whom correspondence should be addressed. E-mail: simonnea@
univ-rennes1.fr.
†
Laboratoire de Chimie Organom e´ tallique et Biologique.
Groupe de Physique Cristalline. E-mail: toupet@univ-rennes1.fr.
‡
(
1) (a) Callot, H. J .; Piechocki, C. Tetrahedron Lett. 1980, 21, 3489.
(
b) Callot, H. J .; Schaeffer, E. Nouv. J . Chim. 1980, 4, 311. (c) Callot,
H. J .; Metz, F.; Piechocki, C. Tetrahedron 1982, 38, 2365. (d) Callot,
H. J .; Metz, F. Nouv. J . Chim. 1985, 9, 167.
(8) (a) Galardon, E.; Le Maux, P.; Simonneaux, G. J . Chem. Soc.,
Chem. Commun. 1997, 927. (b) Lo, W. C.; Che, C. M.; Cheng, K. F.;
Mak, T. C. W. J . Chem. Soc., Chem. Commun. 1997, 1205. (c)
Frauenkron, M.; Berkessel, A. Tetrahedron Lett. 1997, 38, 7175. (d)
Galardon, E.; Le Maux, P.; Simonneaux, G. J . Chem. Soc., Perkin
Trans. 1 1997, 2455.
(
2) (a) Maxwell, J . L.; O’Malley, S.; Brown, K. C.; Kodadek, T.
Organometallics 1992, 11, 645. (b) O’Malley, S.; Kodadek, T. Organo-
metallics 1992, 11, 2299.
(
3) Smith, D. A.; Reynolds, D. N.; Woo, L. K. J . Am. Chem. Soc. 1993,
15, 2511.
4) Wolf, J . R.; Hamaker, C. G.; Djukic, J . P.; Kodadek, T.; Woo, L.
K. J . Am. Chem. Soc. 1995, 117, 9194.
(9) (a) Park, S. B.; Nishiyama, H.; Itoh, Y.; Itoh, K. J . Chem. Soc.,
Chem. Commun. 1994, 1315. (b) Park, S. B.; Sakata, N.; Nishiyama,
H. Chem. Eur. J . 1996, 2, 303. (c) Nishiyama, H.; Aoki, K.; Itoh, H.;
Iwamura, T.; Sakata, N.; Kurihara, O.; Motoyama, Y. Chem. Lett. 1996,
1071.
(10) Chan, Y.; W.; Renner, M. W.; Balch, A. L. Organometallics 1983,
2, 1888.
(11) Hopf, F. R.; O’Brien, T. P.; Scheidt, W. R.; Whitten, D. G. J .
Am. Chem. Soc. 1975, 97, 277.
(12) Collman, J . P.; Barnes, C. E.; Collins, T. J .; Brothers, P. J . J .
Am. Chem. Soc. 1981, 103, 7030.
1
(
(
(
5) Woo, L. K.; Smith, D. A. Organometallics 1992, 11, 2344.
6) Collman, J . P.; Rose, E.; Venburg, G. D. J . Chem. Soc., Chem.
Commun. 1993, 934.
7) (a) Collman, J . P.; Brothers, P. J .; McElwee-White, L.; Rose, E.;
(
Wright, L. J . J . Am. Chem. Soc. 1985, 107, 4570. (b) Collman, J . P.;
Brothers, P. J .; McElwee-White, L.; Rose, E. J . Am. Chem. Soc. 1985,
07, 6110. (c) Collman, J . P.; McElwee- White, L.; Brothers, P. J .; Rose,
1
E. J . Am. Chem. Soc. 1986, 108, 1332. (d) Brothers, P. J .; Collman, J .
P. Acc. Chem. Res. 1986, 19, 209.
(13) Camenzind, M. J .; J ames, B. R.; Dolphin, D. J . Chem. Soc.,
Chem. Commun. 1986, 1137.
S0276-7333(97)00790-5 CCC: $15.00 © 1998 American Chemical Society
Publication on Web 01/23/1998

5
66 Organometallics, Vol. 17, No. 4, 1998
Ta ble 1. 1H NMR Da ta for th e (TP P )Ru [:C(CO
Galardon et al.
2
2
Et) ](L) Com p lexes (δ, p p m )
complex
L
Hpyrrole
Ho
Ho′
Hm,p
CH2
CH3
1
2
3
8.56
8.48
8.44
8.13
7.69
7.67
7.65
2.63
2.57
2.59
0.36
0.32
0.35
7.12 (m, 9H), 6.33 (m, 6H)
6.71 (br, 5H)
8.12
8.18
7.94
8.00
Ta ble 2. Cr ysta llogr a p h ic Da ta for 1
porphyrins, using carbonyl complexes as starting
materials.8
a,d
empirical formula
cryst syst
space group
a (Å)
5 2
C52H42N O Ru‚H O
4
monoclinic
P21/n
18.502(6)
13.552(5)
18.494(6)
90.85(3)
4637(3)
4
Reaction of the carbonyl compound (TPP)Ru(CO)-
4
15
[
EtOH]1 with excess diethyl diazomalonate in reflux-
ing chloroform results in the displacement of the CO
ligand and generation of the dark brown carbene
derivative 1 in 64% isolated yield (eq 1). The (TPP)-
b (Å)
c (Å)
â (deg)
V (Å3)
Z
Fcalcd (g cm-3)
F(000)
1.312
1900
µ(Mo KR) (cm-1)
T (K)
3.81
294
cryst size (mm)
radiation
max 2θ (deg)
scan
0.22 × 0.31 × 0.38
Mo KR
50
ω/2θ ) 1
60
Ru[:C(CO2Et)2][MeOH] compound is air-stable in the
solid state16 and soluble in common polar organic
solvents. This new product has been characterized by
conventional spectroscopic techniques. In particular, its
IR spectrum as a KBr pellet reveals the presence of a
single absorption at 1702 cm-1, attributed to the CO2-
Et groups, and the absence of the CO absorption due to
tmax (for one measmt), s
variance of stds
range of hkl
no. of rflns measd
no. of rflns obsd (I > σ(I))
Rint (from merging equiv rflns)
R(isotropic)
R(anisotropic)
difference Fourier
N(obs)/N(var)
final R
0.2
0-21; 0-15; -21 to +21
7874
3611 (4σ)
0.025
0.105
0.073
0.72-0.20
3611/563
0.057
1
3
the axial ligand. The C NMR spectrum shows a
9
typical low-field signal for the carbene carbon at 271.35
1
ppm, and the H NMR spectrum reveals a quadruplet
a
Rw
Sw
0.051
3.21
0.72, 0.11
and a triplet for the carbene fragment at 2.63 ppm (CH2)
and 0.36 ppm (CH3) (Table 1). These two resonances
are shifted upfield relative to those of the free diethyl
diazomalonate, 4.27 and 1.29 ppm respectively, because
of the porphyrin ring current effect. In UV-vis spec-
troscopy, the coordination of the carbene species slightly
modifies the absorption spectrum of the starting car-
bonyl complex: the Soret band undergoes a 4 nm blue
shift when the Q-band becomes broad and undergoes a
max residual (e Å-3), ∆/σ
a w ) 1/σ(F )2 ) [σ2(I) + (0.04Fo2)2]-1/2.
o
4
nm red shift. All these spectroscopic properties are
in agreement with previous data for (porphyrin)ruthe-
nium carbene complexes.6
,7a
This method was found effective for other diazo
8
a,d
derivatives (RR′CN2: R ) H, CH3, R′ ) CO2Et).
It
represents a useful substitution of the previous methods
which all, except for one,10 used photochemical carbonyl
ejection and formation of either a ruthenium porphyrin
dimer with unencumbered porphyrins or a 14-electron
bare (5,10,15,20-tetramesitylporphyrinato)ruthenium
complex.13 These last two derivatives are highly oxygen
(
14) TPP is 5,10,15,20-tetraphenylporphyrin dianion. (TPP)Ru(CO)-
F igu r e 1. Molecular structure and atom labeling of 1
(phenyl rings are omitted for clarity).
[
EtOH] is a six-coordinate complex containing a weakly bonded axial
ligand (L ) EtOH); such a ligand is easily removed: Bonnet, J . J .;
Eaton, S. S.; Eaton, G. R.; Holm, R. H.; Ibers, J . A. J . Am. Chem. Soc.
1
973, 95, 2141.
15) Caution! The potentially explosive nature of diazo compounds
sensitive, whereas (porphyrin)ruthenium carbonyl de-
rivatives are easily prepared and are air-stable.
Cr yst a l a n d Molecu la r St r u ct u r e of (TP P )R u -
(
should be kept in mind, particularly during distillation: Rosenberg,
M.; Yates, P. Tetrahedron Lett. 1964, 33, 2285.
(16) Although many studies of (porphyrin)iron carbene complexes
[
:C(CO2Et)2][CH3OH]. The diethoxycarbene complex
have been conducted, they are made difficult by the extreme ease with
which iron(II) is oxidized. See for example: (a) Mansuy, D.; Lange,
M.; Chottard, J . C.; Bartoli, J . F.; Chevrier, B.; Weiss, R. Angew. Chem.,
Int. Ed. Engl. 1978, 17, 781. (b) Mansuy, D.; Guerin, P.; Chottard, J .
C. J . Organomet. Chem. 1979, 171, 195. (c) Guerin, P.; Battioni, J . P.;
Chottard, J . C.; Mansuy, D. J . Organomet. Chem. 1981, 218, 201. (d)
Artaud, I.; Gregoire, N.; Battioni, J . P.; Dupr e´ , D.; Mansuy, D. J . Am.
Chem. Soc. 1988, 110, 8714. (e) Artaud, I.; Gregoire, N.; Leduc, P.;
Mansuy, D. J . Am. Chem. Soc. 1990, 112, 6899.
1 forms as purple crystals in the monoclinic space group
P21/n with four molecules per unit cell. Crystallo-
graphic data for the structure determination are given
in Table 2. Figure 1 illustrates the molecular structure
and atom labeling. Selected distances and bond angles
are given in Table 3. As indicated by the structure, the

A New Ru(II) Porphyrin Carbene Complex
Organometallics, Vol. 17, No. 4, 1998 567
Ta ble 3. Selected Bon d Dista n ces (Å) a n d An gle
(
d eg) for 1
Ru-N(1)
Ru-N(2)
Ru-N(3)
Ru-N(4)
Ru-C(45)
Ru-O(5)
2.045(5)
2.045(5)
2.048(6)
2.047(6)
1.829(9)
2.293(6)
C(45)-C(46)
C(45)-C(49)
C(46)-O(1)
C(49)-O(3)
O(1)-C(47)
O(3)-C(50)
1.49(1)
1.51(1)
1.33(1)
1.31(1)
1.47(1)
1.45(1)
C(45)-Ru-O(5)
178.5(3)
carbene complex exists as a 6-coordinate compound,
with a methanol molecule as axial ligand. As expected
for such a complex, the porphyrin ligand is nearly
planar. However, the ruthenium atom is slightly out
of the mean porphyrin plane, 0.12 Å toward the carbene
ligand. A similar situation has previously been ob-
1
1
7
8
served with a (porphyrin)osmium(II) carbene complex
and with a porphyrin rhodium(III) carbene complex.
The Ru-N distances of 2.045(5)-2.048(6) Å all fall
within the range previously reported for diamagnetic
(
TPP)Ru(CO)[EtOH].14 The geometry of the coordina-
tion sphere is close to an ideal octahedral geometry.
Bond angles at ruthenium are in the range 89.1(2)-
9
0.5(2)° for cis angles and 169.5(3)-174.5(3)° for trans
angles. The O-Ru-C(carbene) angle is 178.5(3)°. The
carbene fragment is slightly distorted, since the angle
formed by C(42)-C(45)-C(46) is 112.2(7)°. Such a
value, which is significantly smaller than the 120° angle
2 2
F igu r e 2. Titration curves of a solution of 1 in CH Cl
(2.14 mM) with a solution of PPh in dichloromethane (1.25
3
2
for ideal sp hybridization, has been previously reported
M).
for a (porphyrin)osmium carbene complex: (5,10,15,20-
tetra-p-tolylporphyrinato)osmium (trimethylsilyl)meth-
chemistry of the axial ligands, we decided to investigate
the reaction between 1 and various axial ligands (trans
effect). As in the case with the carbonyl complex,1
the carbene complex of ruthenium porphyrin in solution
shows a large affinity for a second axial ligand and the
magnitude of this effect is dependent on the nature of
the ligand. Nevertheless, this reaction is sufficiently
slow to be monitored by UV-vis spectroscopy.
1
7
ylidene. Steric interactions between the two ethoxy
groups of the carbene fragment and the phenyl groups
of the porphyrin may explain this result. However, a
similar angular value was also found for the bis-
4,21
(
methoxycarbonyl)carbene ligand in the molecular struc-
9
c
ture of (pybox)Ru(Cl)2[:C(CO2Me)2] (pybox ) 2,6-
bis[(4S)-isopropyloxazolin-2-yl]pyridine), which is a non-
porphyrin complex.
The two titration curves with triphenylphosphine and
pyridine are shown in Figures 2 and 3, respectively.
Modification of the wavelength of the Soret band reveals
in both cases the presence of an intermediate (λmax 409
nm for 2 and λmax 410 nm for 3) which appears after
addition of 1 equiv of ligand. These intermediates were
The Ru-C distance of 1.829(9) Å is slightly shorter
than ruthenium-carbon double bonds reported for other
molecular structures of ruthenium carbene complexes.
For examples, the ruthenium-carbon distances in (py-
9
c
box)Ru(Cl)2[:C(CO2Me)2], Ru(Cl)2(PPh3)2[:CH-CHdC-
1
9
20
1
Ph2], and CpRu(I)(CO)[:C(OEt)Ph] are 1.880(7), 1.887-
7), and 1.997(5) Å, respectively. For comparison, the
identified by H NMR spectroscopy as the mixed base-
(
carbene complex 2 (base ) triphenylphosphine) and 3
(base ) pyridine). For example, the spectrum of com-
plex 2 shows only one signal in the region of the
â-pyrrole proton (δ 8.48 ppm) and upfield resonances
corresponding to the carbene moiety (δ 2.57 and 0.32
ppm) with broad signals corresponding to the coordi-
nated base (δ 7.12 and 6.33 ppm) (Table 1). Moreover,
the differentiation of the Ho signals (∆ ) 0.18 ppm) is
in agreement with two different ligated groups. Addi-
tion of a large excess of base results in the formation of
the symmetric bis-ligated derivative, as identified by
MdC distances of the rare (porphyrin)metal carbene
complexes which have been characterized by single-
crystal X-ray diffraction analysis are 1.83(3) Å in (TPP)-
1
6a
Fe[:C(Cl)2][H2O],
1.865(5) Å in (TTP)Os[:C(C6H4-p-
1
7
CH3)2][THF], 1.79(2) Å in (TTP)Os[:C(H)(SiMe3)]-
[
[
THF],17 and 2.030(11) Å in (TPP)Rh(PhCH2NC)-
:C(NHCH2Ph)2]PF6.18
The Ru -O distance of
II
2
.293(6) Å is slightly longer than the corresponding
II
Ru -O distance of 2.21(2) Å found in the similar
complex (TPP)Ru(CO)[EtOH].1
4
2
2,24
1
22,23
UV-vis
and H NMR.
As shown in Figures 2
Liga n d -Exch a n ge Rea ction s. Since the catalytic
role of metalloporphyrins is certainly dependent on the
(21) (a) Tutsui, M.; Ostfeld, D.; Hoffman, L. M. J . Am. Chem. Soc.
1
971, 93, 1820. (b) Chow, B. C.; Cohen, I. A. Bioinorg. Chem. 1971, 1,
(
17) Djukic, J . P.; Smith, D. A.; Young, V. G., J r.; Woo, L. K.
Organometallics 1994, 13, 3020.
18) Boschi, T.; Licoccia, S.; Paolesse, R.; Tagliatesta, P.; Pelizzi, G.;
Vitali, F. Organometallics 1989, 8, 330.
19) Nguyen, S. T.; J ohnson, L. K.; Grubbs, R. H. J . Am. Chem. Soc.
992, 114, 3974.
20) Adams, H.; Bailey, N. A.; Ridgway, C.; Taylor, B. F.; Walters,
S. J .; Winter, M. J . J . Organomet. Chem. 1990, 394, 349.
57. (c) Eaton, S. S.; Eaton, G. R.; Holm, R. H. J . Organomet. Chem.
1972, 39, 179. (d) Eaton, S. S.; Eaton, G. R. Inorg. Chem. 1977, 16, 72.
(22) Ariel, S.; Dolphin, D.; Domazetis, G.; J ames, B.; Leung, T. W.;
Rettig, S.; Trotter, J .; Williams, G. M. Can. J . Chem. 1984, 62, 755.
(23) Antipas, A.; Buchler, J . W.; Gouterman, M.; Smith, P. D. J .
Am. Chem. Soc. 1978, 100, 3015.
(
(
1
(
(24) Brown, G. M.; Hopf, F. R.; Ferguson, J . A.; Meyer, T. J .;
Whitten, D. G. J . Am. Chem. Soc. 1973, 95, 5939.

5
68 Organometallics, Vol. 17, No. 4, 1998
Galardon et al.
First, we examined the possibility of the stoichiomet-
ric carbene transfer reaction from 1 to styrene, although
the complex is quite stable. This transfer was successful
by addition of a 30-fold excess of olefin to 1 in refluxing
toluene, giving the corresponding cyclopropane27 in 66%
yield. Analysis of the ruthenium complex mixture at
the end of the reaction showed the presence of (TPP)-
-1
Ru(CO) (IR: ν 1954 cm , 15%) together with unidenti-
fied products. Such decarbonylation of acid derivatives
by metalloporphyrin complexes is not unusual and has
2
1b,28
already been observed.
Then we investigated the potential of 1 in the
catalyzed formation of olefins and cyclopropanation of
styrene by EDA. When a dichloromethane solution of
1
is treated with excess ethyl diazoacetate, rapid evolu-
tion of gas is observed and high yields (>95%) of diethyl
maleate and fumarate are obtained in the ratio 13.8/1
(eq 2). During this catalytic reaction, 1 is partially
F igu r e 3. Titration curves of a solution of 1 in CH
(
(
2
Cl
2.14 mM) with a solution of pyridine in dichloromethane
1.25 M).
2
and 3, the destabilization of the RudC bond is higher
with triphenylphosphine than with pyridine: the car-
bene ligand is completely displaced after addition of 30
equiv of phosphine, while more than 1000 equiv of
pyridine is required for the carbene exchange under
similar experimental conditions. Thus, coordination of
basic ligands, such as triphenylphosphine and pyridine,
destabilizes the ruthenium-carbene bond and leads to
the axially symmetric bis-ligated complex. Similar
behavior has already been reported by Mansuy and co-
1
transformed (ca. 10%) to the new complex 4. Its H
NMR spectrum displays a singlet at 13.03 ppm, which
allowed us to characterize this product as (TPP)Ru-
[
:C(CO2Et)(H)] by comparison with an authentic sample
prepared from (TPP)Ru(CO)[EtOH] and N2dCH(CO2-
Et). However, in contrast to the catalytic formation of
olefins with (porphyrin)osmium carbene complexes,5
where a bis(carbene) derivative was proposed to be the
intermediate, no evidence of such species could be
obtained with 1 as catalyst. The catalytic reaction of
styrene and EDA was also carried out to give in 85%
yield the corresponding ethyl 2-phenylcyclopropane-1-
carboxylate (eq 3), with trans/cis selectivity (14.0/1)
similar to that observed when (TPP)Ru(CO)[EtOH] was
1
6c
workers with (porphyrin)iron carbene complexes.
We also investigated the interaction between 1 and
CO. During slow bubbling of carbon monoxide in a
solution of 1 in dichloromethane, the reaction mixture
turned red, and a precipitate appeared. Its IR spectrum
revealed, after stirring of the solution under argon and
precipitation of the complex, the presence of a carbonyl
-
1
band at 1943 cm , which is in the range for typical
8
a
ruthenium carbonyl compounds.2
4,25
used as a catalyst.
essentially the original carbene complex and traces of
. Consequently, all these catalytic reactions seem to
The final metal products are
Absence of the
ester band indicates the decoordination of the carbene
moiety. Formation of (TPP)Ru(CO) has been confirmed
4
1
involve a common intermediate, which may be the 14-
electron bare ruthenium porphyrin complex [(TPP)Ru],
but much work is needed to address the mechanistic
issues of these ruthenium-catalyzed processes.
by H NMR spectroscopy. No evidence for a mixed
carbonyl-carbene derivative has been found by moni-
toring the reaction by IR. In all the substitution
reactions, free methanol is detected, as well as some
unidentified organic products resulting from the carbene
ligand removal.
Exp er im en ta l Section
Ca r ben e Tr a n sfer Rea ction , Ca ta lytic F or m a -
tion of Olefin s, a n d Cyclop r op a n a tion . The postu-
late of possible metallocarbenes as active intermediates
Ma ter ia ls. Solvents were distilled from phosphorus pen-
toxide (dichloromethane, chloroform), sodium (pentane), or
sodium benzophenone (toluene). All chemicals were obtained
from Acros Organics and used as received. All manipulations
were carried out under an argon atmosphere.
2
6
in cyclopropanation reactions together with our recent
results in catalysis8 prompted us to investigate the
reactivity of 1 toward ethyl diazoacetate (EDA) and
styrene.
a,d
(27) Fraser, W.; Suckling, C. J .; Wood, H. C. S. J . Chem. Soc., Perkin
Trans. 1 1990, 3137.
(28) Belani, R.; J ames, B. R.; Dolphin, D.; Rettig, S. J . Can. J . Chem.
1988, 66, 2072.
(
(
25) Eaton, G. R.; Eaton, S. S. J . Am. Chem. Soc. 1975, 97, 235.
26) Doyle, M. P. Chem. Rev. 1986, 86, 919 and references therein.

A New Ru(II) Porphyrin Carbene Complex
Organometallics, Vol. 17, No. 4, 1998 569
P h ysica l Mea su r em en ts. UV-visible spectra were re-
was monitored by UV-vis spectroscopy. After about 30 min,
the solvent was removed and the dark brown complex was
washed with pentane and a small amount of methanol. The
final product (622 mg, 64%) was greater than 95% as evidenced
by NMR spectroscopy. Microcrystals suitable for X-ray struc-
ture analysis were obtained by recrystallization from metha-
corded on an Uvikon 941 spectrophotometer in dichlo-
romethane. Infrared spectra were obtained in KBr or CH
2 2
Cl
on a Nicolet 205 FT-IR spectrophotometer. NMR spectra were
1
13
3
recorded in CDCl on 200 DPX ((200 MHz ( H), 50 MHz ( C))
and referenced against the residual proton resonance of the
deuterated solvent. FAB mass spectrometry was performed
by the Centre Regional de Mesures Physiques de l’Ouest
1
nol. H NMR: δ 8.56 (s, 8H); 8.13 (m, 8H); 7.69 (m, 12H);
1
3
2.63 (q, 4H); 0.36 (t, 6H). C NMR: δ 271.36; 173.77; 144.78;
(
CRMPO) at Rennes, France, on a ZabSpec multisources
142.84; 134.82; 133.99; 132.01; 127.92; 126.96; 127.08; 122.98;
-1
-1
spectrometer.
59.28; 14.02. UV-vis: (λabs, nm (ꢀ, M cm )): 406 (126 000);
+
Str u ctu r e Deter m in a tion of 1 by Sin gle-Cr ysta l X-r a y
Diffr a ction . The sample (0.22 × 0.31 × 0.38 mm) was studied
on an ENRAF-Nonius automatic diffractometer CAD4 with
graphite-monochromatized Mo KR radiation. The cell param-
eters were obtained by fitting a set of 25 high-θ reflections.
The data collection (2θmax ) 50°; scan ω/2θ ) 1; tmax ) 60 s;
hkl range h 0-21, k 0-15, l -21 to +21; intensity controls
without appreciable decay (0.2%)) gives 7874 reflections, of
which 3611 are independent (Rint ) 0.025) with I > 4σ(I). After
Lorentz and polarization corrections, the structure was solved
with direct methods, which revealed many non-hydrogen
atoms of the structure. The remaining atoms (and a water
molecule) were found after several scale factor and Fourier
difference calculations. After isotropic (R ) 0.105) and then
anisotropic refinement (R ) 0.073), many hydrogen atoms
were found with a difference Fourier calculation (between 0.72
531 (13 000). FAB mass (m/z): calcd for C51
- MeOH): 872.1951, found 872.1924.
38 4 4
H N O Ru (M
Liga n d -Exch a n ge Rea ction of 1 w ith CO. Carbon
monoxide was bubbled through a solution of 10 mg (10.7 µmol)
of 1 in 5 mL of dichloromethane for 2 h. The reaction mixture
was then stirred under a CO atmosphere for 18 h, before
1
4
isolating the product identified as (TPP)Ru(CO)[EtOH] (89%
yield).
Ca r ben e Tr a n sfer fr om 1 to Styr en e. An 80 mg (86
µmol) amount of 1 and 296 µL (258 µmol) of styrene in 40 mL
of toluene were refluxed for 48 h. The solvent was then
2
9
1
removed and the mixture analyzed by GC and H NMR.
Diethyl 2-phenylcyclopropane-1,1-dicarboxylate was analyzed
by comparison with literature data (66% yield).27
Ca ta lytic F or m a tion of Olefin s fr om EDA. A 167 µL
portion of ethyl diazoacetate (1.607 mmol) was added slowly
(ca. 1 h) via syringe to a well-stirred solution of 10 mg (10.7
µmol) of 1 in dichloromethane. After it was stirred at room
temperature for 15 min, the reaction mixture was analyzed
-
3
and 0.20 e Å ), the remaining ones being set in theoretical
positions. The whole structure was refined by full-matrix
least-squares techniques (use of F magnitude; x, y, z, âij for
Ru, N, and C atoms, x, y, z fixed for hydrogen atoms; 563
1
by GC and H NMR (>95% yield, maleate/fumarate ) 13.8).
2
2
variables and 3611 observations; w ) 1/σ(F
o
)
) [σ (I) +
Ca ta lytic Cyclop r op a n a tion of Styr en e. A 167 µL
portion of ethyl diazoacetate (1.607 mmol) was slowly added
(ca. 1 h) via syringe to a well-stirred solution of 10 mg (10.7
µmol) of 1 and 828 µL (7.232 mmol) of styrene in dichlo-
romethane. After it was stirred at room temperature for 15
2
2 -1/2
(0.04F
o
) ] ) with the resulting R ) 0.057, R
w
) 0.051, and
-3
S
w
) 3.21 (residual ∆F e 0.72 e Å ). Atomic scattering factors
were taken from ref 30. All the calculations were performed
on a Silicon Graphics Indy Computer with the MOLEN
package for refinement and Ortep calculations.
3
1
1
min, the reaction mixture was analyzed by GC and H NMR
(
85%; trans/cis 14/1). anti-ethyl 2-phenylcyclopropane-
Syn th esis of (TP P )Ru [:C(CO Et) ] (1). In a 250 mL
2
2
1
2
1
-carboxylate: 1H NMR (CDCl
3
) δ 7.33-7.08 (m, 5H), 4.18 (q,
three-neck round-bottomed flask fitted with a septum, reflux
condenser, and argon inlet port were added 40 mL of distilled
CHCl and 800 mg (1.08 mmol) of (TPP)Ru(CO)[EtOH]. The
3
H), 2.52 (m, 1H), 1.90 (m, 1H), 1.60 (m, 1H), 1.31 (m, 1H),
.28 (t, 3H).
solution was gently refluxed; then 300 mg (1.62 mmol) of
diethyl diazomalonate was added via syringe. The reaction
Ack n ow led gm en t. We gratefully acknowledge the
financial support of the MESR for a grant to E.G.
(
29) Sheldrick, G. M. In Crystallographic Computing 3: Data
Su p p or tin g In for m a tion Ava ila ble: Tables of bond
lengths, bond angles, general displacement parameter expres-
sions, and positional parameters and figures showing the
complete labeling of atoms (10 pages). Ordering information
is given on any current masthead page.
Collection, Structure Determination, Proteins and Databases; Sheldrick,
G. M., Kr uˆ guer, C., Goddard, R., Eds.; Clarendon Press: Oxford, U.K.,
1
985.
30) International Tables for X-ray Crystallography; Kynoch Press:
Birmingham, U.K., 1974.
31) ENRAF-Nonius Molecular Determination Package; Delft Uni-
versity, Delft, The Netherlands. Current version: 1990.
(
(
OM970790U