acetate; see also in ref. 3c). Sharper signals were observed in the ranges 0
to 10 and 18 to 28 ppm.
§
Crystal data for C34
monoclinic space group P2
molecules in the asymmetric unit. a = 11.1571(9), b = 16.8538(14), c =
H
60
N
6
O
5
F
12
P
2
Mn
2
(6): The compound crystallises in
1
(No. 4) with two symmetrically independent
2
1
=
3.1716(18) Å, g = 98.367(3)°. M
r
= 1032.70, Z = 2 3 2, D
.591 g cm , m = 7.32 cm , absorption correction (Gaussian): min/max
0.787/0.915. 47506 reflexions were collected at 100 K on a BRUKER
SMART CCD using MoK radiation (l = 0.71073Å). The structure was
c
=
23
21
a
solved by direct methods (GENSIN/GENTAN) as implemented in the
XTAL3.4 program package of crystallographic routines.13 7807 observed
reflexions (I > 4s(I)) in final least-squares full matrix refinement of 1099
22
parameters on F terminating at R(R
of fit of 1.7924 and a residual electron density of 22.06/1.94 e Å . CCDC
82/1847. See http://www.rsc.org/suppdata/cc/b0/b007059i/ for crystallo-
graphic files in .cif format.
w
) = 0.084(0.050, w = s ), a goodness
23
1
1
(a) P. Chaudhuri and K. Wieghardt, in Progress in Inorganic Chemistry,
ed. S. J. Lippard, John Wiley and Sons, New York, 1989, vol. 35, p. 329;
(b) E. Kimura, in Progress in Inorganic Chemistry, ed. K. D. Karlin,
John Wiley and Sons, New York, 1994, vol. 41, p. 443; (c) J. A. Halfen,
S. Mahapatra, E. C. Wilkinson, S. Kaderli, V. G. Young, Jr., L. Que, Jr.,
A. D. Zuberbühler and W. B. Tolman, Science, 1996, 271, 1397; (d) C.
Stockheim, L. Hoster, T. Weyhermüller, K. Wieghardt and B. Nuber,
J. Chem. Soc., Dalton Trans., 1996, 4409; (e) K. P. Wainwright, Coord.
Chem. Rev., 1997, 166, 35.
2
3
(a) K. Wieghardt, U. Bossek, D. Ventur and J. Weiss, J. Chem. Soc.,
Chem. Commun., 1985, 347; (b) Review: R. Hage, Recl. Trav. Chim.
Pays-Bas, 1996, 115, 385; (c) K. Wieghardt, U. Bossek, B. Nuber, J.
Weiss, J. Bonvoisin, M. Corbella, S. E. Vitols and J. J. Girerd, J. Am.
Chem. Soc., 1988, 110, 7398; (d) U. Bossek, T. Weyhermüller, K.
Wieghardt, B. Nuber and J. Weiss, J. Am. Chem. Soc., 1990, 112,
Fig. 1 X-band EPR spectra of the electrochemically generated one electron
reduced and oxidised states of the PF -salt of 6 in acetonitrile at 30 K.
6
6
387.
(a) R. Hage, J. E. Iburg, J. Kerschner, J. H. Koek, E. L. M. Lempers,
R. J. Martens, U. S. Racherla, S. W. Russell, T. Swarthoff, M. R. P. van
Vllet, J. B. Warnaar, L. van der Wolf and B. Krijnen, Nature, 1994, 369,
6
37; (b) J. H. Koek, S. W. Russel, L. van der Wolf, R. Hage, J. B.
Warnaar, A. L. Spek, J. Kerschner and L. Del Pizzo, J. Chem. Soc.,
Daltan Trans, 1996, 353; (c) R. Hage, E. A. Gunnewegh, J. Niel, F. S. B.
Tjan, T. Weyhermüller and K. Wieghardt, Inorg. Chim. Acta, 1998, 268,
Scheme 3
4
3; (d) J. H. Koek, E. W. M. J. Kohlen, S. W. Russell, L. van der Wolf,
catalysis. In order to probe this hypothesis and to investigate the
potential of 3 to serve as an asymmetric catalyst we briefly
investigated enantioselective epoxidations of styrenes.
Catalytic activity of 5 was observed in the epoxidation of
2 2
vinylarenes. With H O as oxidant and 2 mol% of catalyst in
P. F. ter Steeg and J. C. Hellemons, Inorg. Chim. Acta, 1999, 295,
189.
(a) D. E. De Vos and T. Bein, J. Organomet. Chem., 1996, 520, 195; (b)
D. E. De Vos and T. Bein, Chem. Commun., 1996, 917; (c) D. E. De
Vos, J. L. Meinershagen and T. Bein, Angew. Chem., Int. Ed., 1996, 35,
4
2
211; (d) Y. V. Subba Rao, D. E. De Vos, T. Bein and P. A. Jacobs,
acetone at 225 °C, approximately 28% conversion of styrene
J. Chem. Soc., Chem. Commun., 1997, 355; (e) D. E. De Vos, B. F. Sels,
M. Reynaers, Y. T. Subba Rao and P. A. Jacobs, Tetrahedron Lett.,
1998, 39, 3221; (f) D. E. De Vos, S. de Wildeman, B. F. Sels, P. J.
Grobet and P. A. Jacobs, Angew. Chem., Int. Ed., 1999, 38, 980; (g) see
also: A. Berkessel and C. A. Sklorz, Tetrahedron Lett., 1999, 40,
7965.
C. Bolm, D. Kadereit and M. Valacchi, Synlett, 1997, 687.
(a) M. Beller, A. Tafesh, R. W. Fischer and B. Schabert, DE 195 23 890
C1; 30.06.95; (b) M. Beller, A. Tafesh, R. W. Fischer and B. Schabert,
DE 195 23 891 C1; 30.06.95.
was observed after 2 h giving the corresponding epoxide with
2
4% ee (S-enantiomer; all ee-values were determined by GC
using a chiral column). Extending the reaction time to 4 h
increased the conversion (ca. 88%) of the olefin but reduced the
enantioselectivity (15% ee). The significantly greater conver-
sion coupled with the lower enantioselectivity after the longer
reaction time suggests that the catalytic species is changing
during the course of the reaction. Substituted arenes, such as
5
6
3
-nitrostyrene and 4-chlorostyrene were epoxidised as well
7
C. Zondervan, R. Hage and B. L. Feringa, J. Chem. Soc., Chem.
Commun., 1997, 419.
giving products with 26 and 21% ee, respectively.
We are grateful to the DFG (SPP Sauerstofftransfer/
Peroxidchemie) and the Fonds der Chemischen Industrie for
support of this research. We thank Professor Dr Wieghardt, Dr
Bill (MPI für Strahlenchemie, Mülheim) and Professor Dr Kölle
8 (a) D. H. R. Barton, W. Li and J. A. Smith, Tetrahedron Lett., 1998, 39,
7055; (b) R. W. Hay, T. Clifford and N. Govan, Transition Met. Chem.,
1998, 23, 619.
9 (a) J. M. Vincent, A. Rabion, V. K. Yachandra and R. H. Fish, Angew.
Chem., Int. Ed., 1997, 36, 2346; (b) R. H. Fish, Chem. Eur. J., 1999, 5,
(
RWTH Aachen) for helpful discussions. We also acknowledge
1
677.
0 (a) G. B. Shul’pin and J. R. Lindsay Smith, Russ. Chem. Bull., 1998, 47,
379; (b) G. B. Shul’pin, G. Süss-Fink and J. R. Lindsay Smith,
Dr Lehmann (MPI für Kohlenforschung, Mülheim) for the X-
1
ray diffraction data collection.
2
Tetrahedron, 1999, 55, 5345.
1
1 (a) M. Rothe, K. D. Steffen and I. Rothe, Angew. Chem., Int. Ed. Engl.,
Notes and references
1
965, 4, 356; (b) C. M. Deber, D. A. Torchia and E. R. Blout, J. Am.
1
†
NMR data of 3: H NMR (CD
3
OD) d 3.12 (dt, J = 2.0, 6.0 Hz, 1H), 3.04
Chem. Soc., 1971, 93, 4893; (c) H. Kessler and A. Friedrich, J. Org.
Chem., 1981, 46, 3892; (d) M. Rothe, M. Fähnle, W. Mästle and K.
Feige, in Peptides, Proceedings of the 9th American Peptide Sympo-
sium, 1985, p. 177; (e) M. Rothe and J. Haas, in Peptides, 1990, ed. E.
Giralt and D. Andreu, ESCOM, Leiden, 1991, p. 212.
(m, 1H), 3.05 (t, J = 13.0 Hz, 1H), 2.76 (dd, J = 8.1, 2.7 Hz, 1H), 2.64 (q,
13
J = 9.0 Hz, 1H), 1.95 (m, 1H), 1.70–1.85 (m, 2H), 1.54 (m, 1H); C NMR
CD OD) d 23.34, 31.40, 57.95, 59.50, 62.17.
Selected analytical data of 6: SIMS (NBA): m/z 742 (M ), 363
LMnOAc), 248 (ligand); C34 Mn 12 required C, 39.5; H, 5.9;
N, 8.1. Found: C, 39.4; H, 5.8; N, 8.1%. UV-Vis: lmax/nm (e, L mol
(
3
+
‡
(
H
N O
60 6 5
2 2
P F
12 After concluding our investigations we were informed that 3 has also
been synthesized by Reggelin and coworkers. We thank Professor
Reggelin (Mainz) for sharing these unpublished results with us.
13 XTAL3.4 User’s Manual, ed. S. R. Hall, G. S. D. King and J. M.
Steward, Universities of Western Australia, Leuven and Maryland,
Lamb, Perth, 1995.
21
21
cm ) 250 (5500); 314 (8500); 485 (400); 521 (340); [a]
D
= +7.1° (c 0.05,
1
CH
3
CN). The H-NMR spectrum of paramagnetic 6 in CD CN exhibits
3
broad signals at d = 2157, 2108, 276, 250, 34, 55, 62, 102, 108 and 116
ppm and an acetate signal at 80 ppm (assigned by exchange with deutero
2436
Chem. Commun., 2000, 2435–2436