10.1002/ejic.202000052
European Journal of Inorganic Chemistry
FULL PAPER
19F NMR (C6D6, 295 K, 376.70 MHz): = 161.5 (m, 2F, m-C6F5), 153.6
(m, 1F, p-C6F5), 122.7 (m, 2F, o-C6F5).
Keywords: zirconium • polymerization • MMA • FLP •
mechanism
{[Zr{5-C5H3-1,2-[SiMe2(1-NtBu)]2}][MeAl(C6F5)3]} (9). 1H NMR (C6D6,
295 K, 400.13 MHz): = 6.65 (s, 2H, C5H3), 1.00 (s, 18H, NtBu), 0.31 (s,
3H, Me), 0.28 (s, 6H, SiCH3), 0.23 (s, 6H, SiCH3). 19F NMR (C6D6, 295 K,
376.70 MHz): = 161.3 (m, 2F, m-C6F5), 153.3 (m, 1F, p-C6F5), 122.7 (m,
2F, o-C6F5).
[1]
[2)
D. G. H. Ballard, P. Vanliend. Makromol. Chem. 1972, 154, 177.
(a) W. B. Farnham, W. R. Hertler. U.S. Patent 4 1988, 728, 706. (b) E.
Y. X. Chen. Chem. Rev. 2009, 109, 5157-5214.
[3]
[4]
Y. Zhang, G. M. Miyake, M. G. John, L. Falivene, L. Caporaso, L.
Cavallo, E. Y. X. Chen. Dalton Trans. 2012, 41, 9119-9134.
H. Yasuda, H. Yamamoto, K. Yokota, S. Miyake, A. Nakamura. J. Am.
Chem. Soc. 1992, 114, 4908-4910.
Formation of [Zr{5-C5H3-1,2-[SiMe2(1-NtBu)]}C6F5] (12). Complexes 6
and 9 in solution evolve to 12, even in benzene-d6 solutions.
{[Zr{5-C5H3-1,2-[SiMe2(1-NtBu)]}C6F5]} (12). 1H NMR (C6D6, 295 K,
400.13 MHz): = 6.79 (m, 3H, C6H5), 1.30 (s, 18H, NtBu), 0.51 (s, 6H,
SiCH3), 0.48 (s, 6H, SiCH3). 13C NMR (C6D6, 295 K, 100.6 MHz): δ =
150.1 (C6F5), 147.8 (C6F5), 139.3 (C6F5), 135.9 (C6F5), 131.3 (C5H3),
128.2 (C5H3), 117.2 (C5H3), 57.4 (NtBu), 34.7 (NtBu), 5.2 (SiMe2), 2.9
(SiMe2). 19F NMR (C6D6, 295 K, 376.70 MHz): = 160.9 (m, 2F, m-C6F5),
153.6 (m, 1F, p-C6F5), 116.1 (m, 2F, o-C6F5).
[5]
[6]
S. Collins, D. G. Ward. J. Am. Chem. Soc. 1992, 114, 5460-5462.
S. Collins, Y. F. Li, D. G. Ward, S. S. Reddy. Macromolecules 1997, 30,
1875-1883.
[7]
[8]
[9]
A. D. Bolig, E. Y. X. Chen. J. Am. Chem. Soc. 2001, 123, 7943-7944.
A. D. Bolig, E. Y. X. Chen. J. Am. Chem. Soc. 2002, 124, 5612-5613.
E. Y. X. Chen, M. J. Cooney. J. Am. Chem. Soc. 2003, 125, 7150-7151.
[10] A. D. Bolig, E. Y. X. Chen. J. Am. Chem. Soc. 2004, 126, 4897-4906.
[11] Y. Ning, E. Y. X. Chen. Macromolecules 2006, 39, 7204-7215.
[12] J. W. Strauch, J. L. Fauré, S. Bredeau, C. Wang, G. Kehr, R. Fröhlich,
H. Luftmann, G. Erker. J. Am. Chem. Soc. 2004, 126, 2089-2104.
[13] G. C. Welch, R. R. S. Juan, J. D. Masuda, D. W. Stephan. Science
2006, 314, 1124-1126.
Methyl methacrylate polymerization. The MMA polymerization runs
were carried out inside of the dry box, at room temperature, in topaz
glass vials equipped with a magnetic stirrer and following a standard
procedure. 4x10-5 mol the precatalyst, the appropriate amount of the
desired cocatalyst and 4 ml of toluene were added to the reactor in that
sequence. The reaction mixture was stirred for 1 minute and 1 ml of
MMA was added. The polymerization reactor was taken out after the
prescribed time and the process was stopped by adding a few milliliters
of acidic methanol. The mixture was precipitated in 50 mL of methanol
and recovered by filtration. The purification of the polymer was carried
out by recrystallization from a saturated solution of PMMA in acetone
which is precipitated in cold methanol. The recrystallized polymer was
filtered again and dried under vacuum at 50 ° C to constant weight.
[14] D. W. Stephan, G. Erker. Angew. Chem. Inter. Ed. 2010, 49, 46-76.
[15] A. M. Chapman, M. F. Haddow, D. F. Wass. J. Am. Chem. Soc. 2011,
133, 18463-18478.
[16] A. M. Chapman, M. F. Haddow, D. F. Wass. J. Am. Chem. Soc. 2011,
133, 8826-8829.
[17] G. Erker. Dalton Trans. 2011, 40, 7475-7483.
[18] A. Berkefeld, W. E. Piers, M. Parvez, L. Castro, L. Maron, O.
Eisenstein. J. Am. Chem. Soc. 2012, 134, 10843-10851.
[19] D. W. Stephan. Accounts Chem. Res. 2015, 48, 306-316.
[20] S. R. Flynn, O. J. Metters, I. Manners, D. F. Wass. Organometallics
2016, 35, 847-850.
Single Crystal X-ray diffraction of 1, 5·0.5C6H6 and 6·C6H6. Data
collection was performed at 200(2) K or 150(2) K, with the crystals
covered with perfluorinated ether oil. Single crystals of 1, 5·0.5C6H6 and
6·C6H6 were mounted on a Bruker-Nonius Kappa CCD single crystal
diffractometer equipped with a graphite-monochromated Mo-Kα radiation
(λ = 0.71073 Å). Multiscan38 absorption correction procedures were
applied to the data. The structure was solved using the WINGX
package,39 by direct methods (SHELXS-13) and refined using full-matrix
least-squares against F2 (SHELXL-16).40 All non-hydrogen atoms were
anisotropically refined except for two tBu groups in 1 and 5 that showed
positional disorder that was treated, and the atoms left isotropic.
Hydrogen atoms were geometrically placed and left riding on their parent
atoms, except for the hydrogens bonded to C13 in compound 1 and C10
in compounds 5 and 6, which were found in the Fourier map and refined
freely. For compound 6, one molecule of solvent crystalized for every
molecule, this molecule shows some disorder, but it was not treated. Full-
matrix least-squares refinements were carried out by minimizing ∑w(Fo2
− Fc2)2 with the SHELXL-97 weighting scheme and stopped at shift/err <
0.001. The final residual electron density maps showed no remarkable
features. Crystallographic data (excluding structure factors) for the
structures reported in this paper have been deposited with the
Cambridge Crystallographic Data Centre as supplementary publication
no. CCDC-1917000 [1], CCDC-1917001 [5·0.5C6H6] and CCDC-
1917002 [6· C6H6].
[21]
J. Cano, P. Royo, M. Lanfranchi, M. A. Pellinghelli, A. Tiripicchio.
Angew. Chem. Int. Ed. 2001, 40, 2495-2597.
[22] J. Cano, P. Royo, H. Jacobsen, O. Blacque, H. Berke, E. Herdtweck.
Eur. J. Inorg. Chem. 2003, 2463.
[23] J. Cano, M. Sudupe, P. Royo, M. E. G. Mosquera. Angew. Chem. Int.
Ed. 2006, 45, 7572-7574.
[24] E. Y. X. Chen, J. Jin, D. R. Wilson. Chem. Comm. 2002, 708-709.
[25] C. Wang, H. K. Luo, M. van Meurs, L. P. Stubbs, P. K. Wong.
Organometallics 2008, 27, 2908-2910.
[26] (a) M. Sudupe, J. Cano, P. Royo, M. E. G. Mosquera, L. M. Frutos, O.
Castaño. Organometallics 2010, 29, 263-268. (b) J. Cano, M. Sudupe,
P. Royo, M. E. G. Mosquera. Organometallics 2005, 24, 2424-2432.
[27]
J. Cano, M. Sudupe, P. Royo. J. Organomet. Chem. 2007, 692, 4448-
4459.
[28] K. Prout, T.S. Cameron, N.P. Rath. Acta Cryst., 1974, B30, 2990.
[29] (a) A. D. Horton, J. de With. Chem. Comm. 1996, 1375-1376. (b) A. D.
Horton, J. de With, A. J. van der Linden, H. van de Weg.
Organometallics 1996, 15, 2672-2674. (c) A. D. Horton, J. de With.
Organometallics 1997, 16, 5424-5436.
[30] F. A. Bovey, G. V. D. Tiers. J. Polym. Sci. 1960, 44, 173-182.
[31] A. Rodríguez-Delgado, W. R. Mariott, E. Y. X. Chen. Macromolecules
2004, 37, 3092-3100.
[32] H. Frauenrath, H. Keul, H. Höcker. Macromolecules 2001, 34, 14-19.
[33] T. Xu, E. Y. X. Chen. J. Am. Chem. Soc. 2014, 136, 1774-1777.
[34] Q. Wang, W. Zhao, S. Zhang, J. He, Y. Zhang, E. Y. X. Chen. ACS
Catal. 2018, 8, 3571-3578.
Acknowledgments
We acknowledge UAH/MICINN (I3 program) and UAH-AE2017-
2 project for financial support. A.L. acknowledges the CAM for a
fellowship.
[35] A. G. Massey and A. J. Park, J. Organomet. Chem., 1964, 2, 245-250.
[36] J. C. W. Chien, W. M. Tsai, M. D. Rausch. J. Am. Chem. Soc., 1991,
113, 8570-8571
This article is protected by copyright. All rights reserved.