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Charge-Transfer Interactions between the Ligands of a Ternary ATP-Cu2+-Phenanthroline Complex.

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at 270 MHz) accessible to us. The temperature dependent
changes in the I3C-NMR spectrum, which are in accord
with the observations in the H-NMR spectrum, however,
offer no additional information. An isomerization of the
two systems requires the cleavage of a metal-olefin bond.
Such a process should lead to coalescence of the two sets
of resonances present at room temperature if it occurs sufficiently fast. This, however, is not observed up to 5 0 ° C ;
above this temperature, the sample starts to decompose irreversibly. On the other hand, a slow isomerization of this
type, as observed for the analogous iron compound at ca.
O°CLlal,cannot be excluded.
3.05
H(2")2.96
I/
H(1")
I
tion. The olefin should occupy an equatorial position in
the trigonal bipyramid; as found for related iron complexes, the phosphane ligand could be coordinated either
a ~ i a l l y [ ~or~eq~atorially'~''.
. ~ ~ . ~ ~ ~ Variable temperature 'HNMR spectra[3b1point toward a fluxional behavior of (S),
effected by olefin rotation (cf. I*]) and/or axial-equatorial
site exchange of the phosphane ligand (cf. L7cE).These results still, however, require completion and confirmation
by the corresponding I3C- and 3'P-NMR spectra.
Tricarbonylbis($-dimethyl fumarate)rutheni~rn'~~]
is the
second complex of this type whose structure has been determined crystallographically["].The structure corresponds
to that of (3). allowing for the presence of the two additional ester groups.
Procedure
2.76
(2) (1.95 g, 3.05 mmol) and methyl acrylate (7.87 g, 91.5
mmol) in 250 cm3 pentane, under argon, are irradiated in
an immersion lamp apparatus (Solidex glass, A2280 nm)
at 10°C with a high-pressure mercury Philips HPK 125
W lamp. After (2) has dissolved completely and the orange
color of the solution has disappeared (1-2 h), the irradiation is continued for ca. 6 h. If necessary, the solution is
filtered and concentrated to about half the original volume. At -80°C (3) precipitates as white crystals, which
are separated from the mother liquor by inverse filtration
and dried in vacuo at -30°C.Yield 1.99 g (3)(61%). M.p.
36 -38 "C.
-
3.70
H (4")
1
H (4:
Received: August 28, 1980 [Z 755 IE]
German version: Angew. Chem. 93, 475 ( 1981)
-6
CAS Registry numbers:
(2). 15243-33-1; (3). 77495-49-9; (4). 77507-03-0; (5). 77495-50-2;
Fig. 1. 270 MHz 'H-NMR spectrum of (3) in CD2C12at 20°C.
There is no indication as yet for a linkage of the methyl
acrylate ligands in (3) to form a carbonylruthenacyclopentane derivative, which should occur at the unsubstituted
C atoms[". However, if (3) is allowed to react with excess
dimethyl 3-cyclobutene-cis-l,2-dicarboxylate,
both methyl
acrylate ligands are displaced and the tricarbonyld-ruthenatricycl0[5.2.O.O~~~]nonane
complex (4) is obtained[61,
by linkage of the.newly entered olefins. The structural ana-
s-
logy between (4) and the corresponding iron c o m p l e ~ ~ ' ~ ]
has been ascertained by X-ray structure
The vibration typical of an "end-on'' coordinated ester group[Ib1
appears at 1629 cm-' in the infrared spectrumr6]of (4).
(CH*=CH-C02CH,X(C,H,)3PlRu(CO),
(-5)
(3) reacts with triphenylphosphane at 0 " C to yield
($-methyl acrylate)tricarbonyl(triphenylphosphane)ruthenium (5)I6];some tricarbonylbis(tripheny1phosphane)ruthenium is also formed as a by-product, the relative amount
of which increases with rising temperature. Thus, the n-donor ligand displaces methyl acrylate instead of inducingas intended-the linkage to a ruthenacyclopentane complex. It is inferred from the IR spectrum'61of (5) that several (presumably three) distinct species are present in solu-
460
111 a) F.- W. Greuels, D. Schulz, E. Koerner uon Gusto$, Angew. Chem. 86,
558 (1974); Angew. Chem. Int. Ed. Engl. 13,534 (1974); b) 8. E. Fouiger.
F.- W. Greuels, D. Hess, E. A. Koemer von Gustorf: J. Leitich, J. Chem.
SOC., Dalton Trans. 1979, 1451.
[2] a) F.- W. Grevels, J. G. A . Reuvers. J . Takats, J. Am. Chem. SOC.,in press;
b) B. F. G. Johnson, J. Lewis, M. V. Twigg, J. Organomet. Chem. 67, C75
(1974); c) L. Kruczynski, J. L. Martin, J. Takats, ibid. 80,C 9 (1974).
[3] a) R. G. Austin. R . S. Paonessa. P. J. Giordano. M . S. Wrighton, Adv.
Chem. Ser. 168, 189 (1978); b) F,-W. Grevels, J . G.A. Reuvers, J . Takats,
unpublished results.
[4] a) F.- W. Greuels, K . Schneider, C. Kriiger, R . Goddard. Z. Naturforsch. B
35,360 (1980); b) L.-K. Liu. C. Kriiger, in press.
[5] A. Stockis, R. Hoffmann. J. Am. Chem. SOC.102,2952 (1980).
[6] (4): m.p. 126-130°C (dec.). IR (n-hexane): metal carbonyl region,
9=2080, 2015, 1980.5 crn-'; ester carbonyl region, ?= 1749, 1736.5, 1629
cm-'. 'H-NMR (C,D,): 6=3.19, 3.28, 3.40, 3.42 (4CH,), 2.8-3.8 (8H).
The mass spectrum shows the molecular ion and the successive loss of
3CO (m/e=526, 498, 470, 442; "*Ru). (5): m.p. 107--109°C (dec.). IR
(n-hexane): metal carbonyl region, 9=2083 m, 2067 m, 2058 w, 2007 sst,
1968 st, br c m - ' ; ester carbonyl region, ?= 1714-1702 br c m - ' .
171 a) C . Kriiger. Y.-H. Tsay, personal communication; b) Cryst. Struct.
Commun. 5,219 (1976); c) J. A. Osborn. J. Takats et a/.. unpublished results.
[S] a) L. Kruczynski, L. K . K . LiShingMan, J . Takats, J. Am. Chem. SOC.96.
4006 (1974); b) S. T. Wilson, N . J . Coville. J . R. Shapley. J. A. Osborn,
ibid. 96, 4038 (1974).
[9] C. Kriiger, C. Woimershauser, personal communication.
0 Veriag Chemie GmbH, 6940 Weinheim. 1981
Charge Transfer Interactions between the Ligands
a Ternary ATP-Cd+-Phenanthroline Complex
of
By William S . Sheldrick"]
Ternary complexes of metal ions play a significant role
in biological processes, e. g. as enzyme-metal ion-substrate
1'1 Priv.-Doz. Dr. W. S. Sheldrick
Gesellschaft fur Biotechnologische Forschung mbH
Mascheroder Weg I , D-3300 Braunschweig-Sfockheim(Germany)
0570-.0833/81 /0S05-460 $ 02.50/0
Angew. Chem. tnt. Ed. Engl. 20 (1981) No. 5
complexes. Although the enzymatic phosphate transfer requires, in most cases, a divalent metal ion M2 -under
physiological conditions Mg2 - and ternary enzymeM 2 + - A T P complexes are involved in this reaction, no
structure of a ternary ATP complex has previously
been determined. Furthermore, no X-ray structural analysis has been carried out o n a binary metal ion-ATP
complex. On the basis of ' H - N M R studies"] o n the
model systems Cu(ATP)(bpy)'- [bpy = 2,2'-bipyridyl] a n d
M(ATP)(phen)*- [MZf = Mg2+, Zn2+; p h e n = 1,lO-phenanthroline], which are significantly more stable than the
corresponding binary complexes M(ATP)*-, it has been
suggested that these adducts may display a metal ionbridged conformation, which allows a charge transfer interaction between the 2,2'-bipyridyl o r 1 ,lo-phenanthroline
ligands and the adenine base. In this proposed structure,
the metal ion coordinates both the B- and y-phosphate oxygens of the ATP. We have now isolated the ternary complex [Cu(ATP)(phen)], . 7 H 2 0 ( I ) at p H = 2.8 and report
here its molecular structure (Fig.
At this pH, N 1 of the
adenine is p r ~ t o n a t e d [ ~ ] .
+
+
(XCN=69and 39", yoc=66.3 and 48.6"), whereas one ribose
moiety adopts a C3'-endo-, the other a C2'-endeconformationl'].
The crystal structure of ( I ) is stabilized by both intra- and
intermolecular interactions between adenine and phenanthroline systems. The shortest intramolecular distances to the atoms
of a phenanthroline system are observed for C8 of the first adenine [331.7 pm] and C5 of the second adenine [348.5 pm]. The
base planes are not quite parallel to one another [angles =6.7
and 5.8"]. This structure demonstrates that base stacking may
be observed in ternary ATP complexes together with the involvement of all three phosphate functions in the metal coordination (the a-function albeit to a lesser extent) without the
nucleotide being forced to take up an unusual conformation.
In accordance with the observed structures of ternary complexes of nucleotide monophosphates[61,the adenine bases are
not involved in coordination to the metal ions. It can, therefore, be assumed with some degree of certainty that metal ions
preferentially coordinate the phosphate oxygens in enzymemetal ion-ATP complexes.
1,lO-Phenanthroline may be regarded as a simple model for
an enzyme which binds M(ATP)2- more strongly than M Z +or
A T P - alone, e. 9. the system arginine kina~e/Mn(ATP)'-['~.
The present results then suggest that charge transfer interactions may play an important role in the increased stability of
enzyme-M2+-ATPcomplexes.
Experimental
0.28 g (0.5 mmol) ATPNa2 in 3 cm3 H 2 0is added with stirring to a solution of 0.10 g (0.5 mmol) C U ( N O ~and
) ~ 0.10 g
(0.5 mmol) 1,lO-phenanthroline in 6 cm3 H 2 0 at 80°C. The
pH value is adjusted to 2.8 and the temperature held at 80°C
for 30 min. Blue-green prismatic crystals precipitate upon slow
cooling. ( I ) , which is obtained in quantitative yield, is filtered
off and washed with water and methanol.
Received: September 1, 1980 [Z 756 IE]
German version: Angew. Chem. 93,473 (1981)
CAS Registry numbers
(1). 77507-04-1
Fig. I. Molecular structure of [Cu(ATP)(phen)],.
d!P
Both independent Cu atoms in ( I ) display a strongly distorted [4 21-octahedral coordination. In each case a-, p- and
y-phosphate oxygens of an ATP are coordinated by the same
Cu2+ ion. The two phenanthroline N atoms, one ATP p- and
one ATP y-phosphate oxygen provide the equatorial ligands.
The following distances were determined: Cu-Op 194.2(9)
and 197.7(9); Cu-0,
192.5(8) and 191.9(8); (OB-)Cu-N
198.9(10) and 205.0(12); (0,-)Cu-N
201.3(10) and 199.3(11)
pm. The coordination sphere is completed by one a-phosphate
oxygen of the same ATP and one y-phosphate oxygen of the
other ATP. However, the axial Cu-O,(-H)
interaction is
weak [Cu.. .O,(-H) =287.8(9) and 273.0(8) pm]. In contrast,
the axial Cu-0,
distances are 228.4(8) and 227.3(9) pm reinteraction,
spectively. As a result of the weak Cu-O,(-H)
the coordination of the Cu atoms is distorted somewhat in the
direction of a square pyramidal geometry. C u l is displaced 4.4
pm from the best equatorial plane in the direction of the Cu-0, axial bond and Cu2 by 4.3 pm. Both adenosine moieties
display similar nucleotide configurations; the observed values
lie in the typical regions for purine nucleotides. The conforma= 32.3 and
tions at the glycosidic C1'-N9 bond are anti kCN
5.7"), those at the C4'-C5'
bond gauche-gauche (yo== 59.6
and 50.1°)141.The ribose moieties display the C3'-end@conformation. Similar conformations are observed for both independent ATP molecules in the crystal lattice of ATPNa,. 3 H 2 0
+
Angew. Chem. lnt Ed. Engl. 20 (1981) No. 5
[I] C. F. Naumann, H.Sigel, I. Am. Chem. SOC.96, 2750 (1974); P. R. Mirchel. H .
Sigel. ibid. 100, 1564 (1978).
I21 (1). C W H U N M O ~ ~ PH,O,
~ C Ucrystallizes
~.~
monoclinic, P2,, with a= 1180.7(3),
6=2482.4(5), c=1069.3(2) pm, 8-94.98(3)", Z=2,pc,,,=1.73 g crw3. The
structure was refined to R=0.069, Rw-0.067 for 3649 independent reflexions
(28-Z 120". CuK-radiation, F2>2.0u(Fz).Cu, Pand 0 atoms received anisotropic temperature factors. Of the 7 crystal water molecules, 4 are disordered.
131 C. F. Naurnann. B. fibs. K Sigel, Eur. J. Biochem. 41, 209 (1974).
I41 Definitions of ,yCN and vocare given in M. Sundaralingam, Ann. N. Y . Acad.
Sci. 255, 3 (1975).
I51 0. Kennard, N . W.Isaacs. W.D . S. Motherwell, J. C. Coppola, D. L. Wampler.
A. C. Larson. D. G. Watson. Proc. R. SOC.(London) A 325. 401 (1972).
[61 Chaiau-Yu Wei, B. E. Fischer, R. Bau. J. Chem. SOC.Chem. Commun. 1978,
1053; K. Aoki, J. Am. Chem. SOC.100,7106 (1978).
[71 D. H . Bufflaire.M. Cohn, J. Biol. Chem. 249, 5733, 5741 (1974).
Insertion of -CN
into the Metal-Carbene Carbon Bond:
A Route to Methyleneaminocarbene Complexes
By Helmut Fischer and UIrich Schubert"'
Owing t o the polarity of the CN-bond, azomethines
R'-N=CR2R3
react with a wide variety of substrates"].
Complexes formed by replacement of one of the substituents (R', R' o r R3)are therefore especially suited for stu-
[*I Dr. H.Fischer, Dr.
U. Schubert
Anorganisch-chemisches lnstitut der Technischen Universitat Miinchen
Lichtenbergstr. 4, D-8046 Garching (Germany)
0 Verlag Chemie GrnbH, 6940 Weinheim. 1981
0570-0833/81/050S-461$
02.50/0
461
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atp, cu2, complex, interactions, ternary, transfer, phenanthroline, ligand, charge
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