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Heterometal Binuclear Complexes with Thio- and Selenoformaldehyde as Bridge Ligands.

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the center 3 of the naphthoquinone radical anion, caused
by the M"%-inducedelectron density flux to the quinone
oxygen of the contact ion-pair [z>C+OQ-. .,"%I.
Received: August 8, 1983 [ Z 508 IE]
German version: Angew. Chem. 96 (1984) 74
CAS Registry numbers:
1, 77 101-98-5; 2, 88288-46-4; 3a, X8288-47-5; 3b, 88288-48-6; 3c, 88288-497; 3d, 88288-50-0; 3e, 88288-51-1 ; 48, 88288-53-3; 4b, 88288-55-5; 4c,
88295-44-7; 4d, 88288-57-7.
[I] a) C. J. Pedersen, H. K. Frensdorff, Angew. Chem. 84 (1972) 16; Angew.
Chem. Int. Ed. Engl. I 1 (1972) 16. b) J. M. Lehn, Acc. Chem. Rex 11
(1978) 49; c) cf. the summaries by F. Vogtle, E. Weber, U. Elben in Kontukte 1981 No. 1 p. 24 and relerences cited therein.
121 J. P. Dix, F. Vogtle, Angew. Chem. 90 (1978) 893; Angew. Chem. Int. Ed.
Engl. 17(1978) 857; Chem. Biv. 114 (1981) 638.
[3] Cf. M. Lnbitz, M. Plato, K. Mobius, R. Biehl, J . Phys. Chem. 83 (1979)
3402, and references cited therein.
[4] Cf. e.g. M. Brustolon, L. Pasimeni, C. Corvaja, J. Chem. SOC. Faraduy
Trans. 2 71 (1975) 193; R. Allendoerfer, D. Eustall, J . Phys. Chem. 75
(1971) 2765.
Fig. 1. 'H-ENDOR-spectrum of 3c at 202 K. Measurement conditions: 920 MHz, microwave power 9 dB, radiowave power 150 W, duration of recording 2000 s, time constant 1s. Assignment according to INDO open-shell
2-dimethylaminonaphthoquinone radical
anion
calculation
for
(aH.3 *aH.6> aH.5= a H . 8 >
>~HNcH,).
- The ESR spectra of the ion-pairs 3 reported here do not
show the temperature-dependence known for quinone
radical anions'41. No I4N-coupling can be observed, a
finding, which is consistent with a fixation of the N-electron pair in the naphthaquinone 71-nodal plane and directed outwards from the solvate cage, and thus with a
rigidization of the molecular skeletal framework on metal-cation complexation.
- Addition of anhydrous alkaline-earth perchlorates in
THF leads to a significant change in the ESR data, as
expected for an increased charge of the complexed cations 4.
In the ESRIENDOR spectra of the radical anions of the
naphthoquinone-crownether-metal complexes presented
here (cf. Fig. l), the largest coupling, assigned to the proton in position 3, reveals most markedly its dependence on
charge and radius of the metal cation (Fig. 2), as is typical
for contact ion-pair interaction~[~].
The measurement data (Fig. 2), can be rationalized
straightforwardly by an increase of the spin population at
ImTl
0.4
0.3
Heterometal Binuclear Complexes with
Thio- and Selenoformaldehyde as Bridge Ligands**
By Helmut Werner* and Wilfried Paul
Recently, three independent research groups reported
the successful fixation of CH,Se, a molecule which is extremely unstable in the free state, by complexation in transition-metal complexes[']. Headford and Roper""], like
us[1c1, used an iodo(iodomethy1)metal compound
L,M(CH,I)I as starting material and converted this by
reaction with NaSeH into the corresponding selenoformaldehyde
complex
L,,M(q2-CH2Se), in
which
(L,M =(PPh3)2(CO)zOs[1"1,CSH,(PMe,)Rh[lcl). Herrmann
et al.[Ib1chose another synthetic concept, namely that of
methylene addition to bonds between main group elements
and transition metals, and thus obtained from (pSe)[(Mn(CO),C,R,], (R= H, Me) and diazomethane the
binuclear complex (p-CH2Se)[Mn(C0),C5R,I,; in these dimanganese compounds two identical metal-complex fragments are bridged by the CH,Se ligand.
Structurally similar compounds, but with two different
metal-ligand groups bridged by CH,Se, are readily obtainable from the mononuclear rhodium complex 1 and the tetrahydrofuran adducts M(CO), .THF (M = Cr, W) or
C5HsMn(C0)z THF"]. The structure proposed for the
products 2-4 is in good agreement with the spectroscopic
data summarized in Table I . In the 'H-NMR spectra, the
occurrence of two signals for the diastereotopic CH,Se
protons is characteristic; they are shifted upfield compared
to the signals of
The difference in the &values of the
CHZsignals is substantially greater than in the case of the
dimanganese compounds (p-CH2Se)[Mn(CO)ZC5Rs]2,in
which it is 0.22 (R= H) and 0.70 ppm (R= Me)['b1.
The sulfur atom of a mononuclear (q2-CH,S)-metal
compound can also function as donor towards a 16-electron complex fragment such as Cr(CO),: Compound 6 is
1'1 Prof. Dr. H. Werner, W. Paul
Institut fur Anorganische Chemie der Universitat
Am Hubland, D-8700 Wurzburg (FRG)
1
I**]
This work was supported by the Deutsche Forschungsgemeinschaft, the
Fig. 2. Correlation of the coupling constants aH,3of the radical anions 3 and
4 with charge n" and radius 1/rM"e of the complexed metal ions.
58
0 Verlag Chemie GmbH, 0-6940 Weinheim, 1984
Fonds der Chemischen Industrie, and by gifts of chemicals from BASF
AG and Degussa AG. We thank Dr. G. Lange as well as Dr. W. Buchner
and C. P. Kneis for recording the mass and NMR spectra.
0570-0833/84/0101-00S8 $02.50/0
Angew. Chem. Int. Ed. Engl. 23 (1984) No. 1
Table 1. Spectroscopic data of the complexes 2-4 and 6.
IR:
v(C0) [cm-'1
2
3
4
6
2050, 1980
1930, 1900
(in THF)
1985, 1930
1925, 1910
(in pentane)
1960, 1900
1830
(in Nujol)
1975, 1935
1930, 1920
(in pentane)
5.13 (dd)
0.7
1.2
4.88 (dd),
2.0
1.0
0.66 (dd)
1.o
10.2
3.56 (ddd)
I .o
10.6
1.0
2.29 (d)
166.7
5.17 (dd)
0.7
1.2
5.18 (ddd),
2.0
0.7
0.8
0.71 (dd)
1.0
10.4
2.31 (d)
168.2
3.76 (ddd)
0.8
10.5
0.8
5.41 (dd) [b]
0.6
1.4
4.72 (dd),
3.54 (ddd)
2.2
0.8
10.2
0.8
0.8
1.32 (dd)
1.0
10.3
2.39 (d)
174.2
5.07 (dd)
0.7
1.1
3.97 (dd),
0.6
1.5
0.57 (dd)
0.8
2.67 (ddd)
0.4
7.8
1.5
10.2
2.37 (d)
169.7
[a] 2 , 3, and 6 in C6D6, 4 in ID,]acetone. [b] G(CSHsMn)=4.38 (s).
l , E = Se;5,E = S
2,E
=
S e , M L , = Cr(CO)E
3 , E = S e , M L , = W(CO)5
4 , E = S e , M L n = Mn(CO)zC&15
6 , E = S , ML, = C r ( C O ) 5
formed from 5l''l and Cr(CO)S.THF under the same conditions as for the reaction 1-+ 2[']. A corresponding binuclear complex in which a thioformaldehyde ligand bridges
two Mn(C0)&H5 fragments was prepared by Herberhold
et al. using Herrmann's
The possible general applicability of the method developed for the synthesis of 1 and 5 is demonstrated by the
synthesis of 7[41from C5Mes(CO)Rh(CHzI)I[SI.The selenoformaldehyde complex 7 also behaves like a Lewis base
and reacts with M(CO)s.THF (M = Cr, Mo) to give the heterometal binuclear complexes 8 and 9I4]. This indicates
that neutral CH2S- and CH,Se-transitionmetal compounds presumably react in general as two-electron donors, both towards alkylating agents['"*"'as well as towards
complex fragments such as Cr(CO),, Mn(C0)2C5H5,etc.
The cation [C5HsRe(q2-CH2S)(NO)PPh3]'does not appear
to be capable of this[61,possibly due to the positive charge,
and the consequently lower electron density at the sulfur
atom.
[l] a) C. E. L. Headford, W. R. Roper, J. Organomet. Chem. 244 (1983) C53;
b) W. A. Herrmann, J. Weichmann, R. Serrano, K. Blechschmitt, H. Pfisterer, M. L. Ziegler, Angew. Chem. 95 (1983) 331 ; Angew. Chem. Int. Ed.
Engl. 22 (1983) 314; Angew. Chem. Suppl. 1983, 363-395; c) W. Paul, H.
Werner, Angew. Chem. 95 (1983) 333; Angew. Chem. Int. Ed. Engl. 22
(1983) 316; Angew. Chem. Suppl. 1983, 396-404.
[2] General procedure: A solution of M(CO), or CsHsMn(C0)3 (1.0 mmol)
in THF (50 mL) is irradiated until evolution of CO ceases (ea. 2-3 h).
After addition of 100 mg (0.3 mmol) 1 [lc], the solution is stirred for ca.
24 h at room temperature, the solvent removed in vacuo, and the residue
extracted with benzene. The extract is concentrated to a few mL and
chromatographed on Al2O3 (Woelm, Activity IV) with benzene. Recrystallization of the products from pentane; yield 59% (Z), 28% (3) and 87%
(4), respectively. The preparation of 6 from Cr(CO), and 5 is carried out
analogously; yield 20Oh.- 2 : orange crystals, m. p. 128"C (dec.), relative
molecular mass M,=530 (MS); "C-NMR [400 MHz, 2 5 T , C6D6, int.
TMS]: G(CO-trans)=222.83 (s), G(CO-cis)=218.50 (s), S(CsHs)=87.64 (s),
6(CH2)=43.06 (dd, JRhC=22.3, Jpr=7.9 Hz), 6(Me3P)= 17.94 (d,
Jpc=32.5 Hz).-3: orange crystals, m.p. 31°C (dec.), Mr=662 (MS).-4:
dark red crystals, m.p. 117°C (dec.), M,=514 (MS).-6: yellow crystals,
m.p. 96°C (dec.), M,=482 (MS).
[3] M. Herberhold, W. Ehrenreich, W. Biihlmeyer, Angew. Chem. 95 (1983)
332; Angew. Chem. I n f . Ed. Engl. 22 (1983) 315.
[4] 7 can be prepared analogously to 1 [lc] from C5MeS(CO)Rh(CH21)I[5]
and NaSeH; yield 73%. The synthesis of 8 and 9 proceeds analogously to
that of 2-4; yield 39 and 88%, respectively.-7: red crystals, m.p. 119°C
(decomp.), Mr=360 (MS); IR [Nujol): v(C0)=2010 cm-I; 'H-NMR
[c&,]: 6(CSMes)=1.69 (d, J ~ h ~ z 0 Hz),
. 4 6(CH2)=5.56 (dd, JnhH=0.7,
JHH= 2.0 Hz) and 4.56 (dd, JRhH
= 2.0, JIIH
= 2.0 Hz).- 8: dark red crystals, m.p. 85°C (dec.), M,=552 (MS); 1R [pentane]: v(C0)=2058, 2020,
1940, 1935, 1925 cm-I; 'H-NMR [C&,]: 6(C5Me5)=1.35 (d, J ~ h ~ = 0 . 5
HZ), 6(CH2)=4.93 (dd, JRhH=0.2, J H I I =HZ)
~ .and
~ 3.88 (dd, JRhH=2.5,
JHH==0.7Hz).-9: red crystals, m p . 84°C (dec.), M,=598 (MS); IR[pentane]: v(C0)=2065,2055,2020, 1990, 1940, 1925 cm-'; 'H-NMR [C,D,]:
6(CsMes)= 1.49 (d, JRhH=0.5 Hz), 6(CH2)=5.09 (dd, JnhH=0.2,
JHH
= 4.9 Hz) und 4.09 (dd, JKhH
= 2.3, JHH= 4.9 Hz).
[5] H. Werner, W. Paul, J . Organomel. Chem. 236 (1982) C71.
[6] W. E. Buhro, A. T. Patton, C. E. Strouse, J. A. Gladysz, F. B. McCormick,
M. C. Etter, J. Am. Chem. Soc. 105 (1983) 1056.
1,3-Bis(tri-tert- butylsily1)triazene"*
7
8, M
[ R h l = C,NIe5(CO)Rh
= C r ; 9, M = M o
Received: August 15, 1983 [Z 517 IE]
German version: Angew. Chem. 96 (1984) 68
CAS Registry numbers:
1, 85202-36-4; 2, 88288-37-3; 3, 88288-38-4;4, 88288-39-5;5, 85202-35-3;6,
88288-40-8; 7, 88288-41-9; 8, 88288-42-0; 9, 88288-43-1.
Angew. Chem. Int. Ed. Engl. 23 (1984) No. I
By Nils Wiberg*, Gerd Fischer, and Petros Karampatses
Whereas silyl derivatives of diazene 1['I and 2-tetrazene
3[21
are well known, our attempts to synthesize silyl derivatives of the triazene 2, a previously non-isolable nitrogen
(*I Prof. Dr. N. Wiberg, Dr. G. Fischer, P. Karampatses
Institut fur Anorganische Chemie der UniversitBt
Meiserstrasse 1, D-8000 Miinchen 2 (FRG)
[**I Silicon Compounds, Part 56.-Part 55: N. Wiberg, G. Wagner, Angew.
Chem. 95 (1983) 1027; Angew. Chern. Int. Ed. Engl. 22 (1983) 1005.
0 Verlag Chemie GmbH, 0-6940 Weinheim. 1984
0570-0833/84/0101-0059 $02.50/0
59
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