Y, el tercer eje, en el cual convergen los puntos clave antes mencionados se resume en la idea de que “Todo Comunica Salud”, y trata de impulsar a la

Future work on these complexes would entail synthesis and isolation of zirconocene dimethyl complexes with pendant borate anions which will then be reacted with cationizing reagents such as [Ph3C][B(C6F5)4] or [PhNMe2H][B(C6F5)4] to yield zwitterionic

complexes (Scheme B.4). These complexes should be active for the polymerization of propene and analysis of the propene produced by these reactions will provide valuable insight into the effect of anions on polymerizations.

Scheme B.4

If strong anion pairing effects exist then it should be manifest as a move toward isotacticity in polypropene from the (Ewen)ZrCl2-derived complex. As the anion is constrained to one

side of the metallocene wedge there should be an energy difference between the two conformations of the catalyst with the polymeryl chain on opposite sides of the metallocene wedge (Scheme B.5). Site epimerization would be expected to cause the chain to swing to the side away from the anion to give the more stable complex. This site epimerization would be expected to result in more insertions from one side of the wedge yielding a more isotactic polymer. Increasing propene pressures would be expected to counteract this effect resulting in more syndiotactic polypropene.

Scheme B.5

B.6Experimental

General Considerations. All operations were carried out under a protective dinitrogen or

argon atmosphere, either in a glovebox or on a vacuum manifold. Benzene-d6 and other solvents used were dried by vacuum transfer either from sodium benzophenone. NMR spectra were obtained using Varian Inova 500 or Mercury 300 spectrometers. 1H chemical shifts are referenced to residual solvents peaks (7.16 ppm) for 1H benzene. 19F chemical shifts were referenced to an external standard of neat CFCl3 at 0.00 ppm. HB(C6F5)2 was

prepared by Alex Miller following the procedure of Piers.51 Me(3- butenyl)C(C5H4)(fluorenyl)ZrCl2 was prepared following literature methods.43 Zr(NMe2)4

Me(vinyl)Si(3-tBu-C5H4)Cl. 1.7405 g (13.583 mmol) Li(tBuC5H4) was weighed into an

oven dried 250 mL round bottom flask and a 180º joint was attached. Into a second 250 mL oven dried round bottom with attached 180º joint was vacuum transferred 12.0 mL (91.9 mmol, 6.76 equiv) Me(vinyl)SiCl2. ~ 75 mL of thf and Et2O were vacuum transferred from

a Na/Ph2CO pot onto the Cp and silane respectively. The Cp solution was slowly

transferred onto the silane solution at –78 ºC via cannula. The reaction was allowed to warm to room temperature with stirring. The solution was allowed to stir overnight after which time the solvent was pumped off to yield a white powder and orange liquid. The mixture was taken into the glove box, taken up in petroleum ether and filtered through celite to remove the LiCl byproduct. The petroleum ether was pumped off to yield 2.9442 g (96% yield) of Me(vinyl)Si(3-tBu-C5H4)Cl as an orange oil. 1H NMR revealed two isomers

as expected for a protonated disubstituted Cp ring. 1H NMR (300 MHz, benzene-d6) δ 6.64

(s, 2H, Cp-H), 6.47 (d, J = 18 Hz, 2H, Cp-H), 6.12 (dd, J = 11, 9 Hz, 3H, Cp-H), 5.86 (m, 8H, Cp-H, =CH-), 1.14 (s, 18H, C(CH3)), 0.11 (s, 3H, Si-CH3), 0.09 (s, 3H, Si-CH3).

Me(vinyl)Si(3-tBu-C5H4)(C5H5). 2.1490 g (13.910 mmol) of MgCp2 was weighed into an

oven dried 100 mL round bottom. 3.1398 g (13.843 mmol) of Me(vinyl)Si(3-tBu-C5H4)Cl

was added as a petroleum ether solution and a 180º joint was attached. The solvent was removed under vacuum and ~45 mL of thf was vacuum transferred in from a Na/Ph2CO

pot at –78 ºC. The reaction was allowed to warm to room temperature with stirring overnight. The thf was removed under vacuum to give a red oil. The oil was taken up in Et2O and washed with saturated aqueous NH4Cl followed by 3 washes with water. The

g of a yellow oil (94 % yield) which was shown to be Me(vinyl)Si(3-tBu-C5H4)(C5H5) by

GC-MS.

Me(vinyl)Si(3-tBu-C5H3)(C5H4)Zr(NMe2)2. 0.5232 g (1.956 mmol) of Zr(NMe2)4 was

weighed into a 100 mL oven dried round bottom flask to which was attached a condenser and 180 º joint. To a second 100 mL oven dried round bottom flask was added 0.5010 g (1.954 mmol, 1 equiv) Me(vinyl)Si(3-tBu-C5H4)(C5H5). ~ 50 mL toluene were vacuum

transferred onto the ligand from a Na/Ph2CO pot. The ligand solution was cannula

transferred into the flask containing the Zr. Heating with stirring to 50 ºC resulted in the immediate evolution of an orange color. Over the course of 1 hour the temperature was increased to 100 ºC with an Ar flow over the reaction. The reaction was kept at 100 ºC for 36 hours until the Ar flow was no longer basic (no more HNMe2 evolution). The reaction

was allowed to cool to room temperature and the toluene was removed under vacuum to give a gooey solid of reddish color. In the glove box the goo was taken up in petroleum ether and filtered. Removal of the petroleum ether affored 727.2 mg (86% yield) of Me(vinyl)Si(3-tBu-C5H3)(C5H4)Zr(NMe2)2 as a red solid. 1H NMR revealed a 1.08(1):1

mixture of the two possible diastereomers. 1H NMR (300 MHz, benzene-d6) δ 6.55 (m, 6H,

=CH-/Cp-H), 6.17 (m, 3H), 6.09 (d, J = 2 Hz, 1H), 5.93 (dd, J = 5, 2 Hz, 1H, Cp-H), 5.83 (dt, J = 5, 2 Hz, 2H, Cp-H), 5.77 (dd, J = 4.9, 3 Hz, 2H, Cp-H), 5.68 (dd, J = 4, 3 Hz, 1H, Cp-H), 5.63 (t, J = 3 Hz, 1H, Cp-H), 5.56 (t, J = 3 Hz, 1H, Cp-H), 2.90 (s, 6H, N(CH3)2),

2.87 (s, 6H, N(CH3)2), 2.58 (s, 6H, N(CH3)2), 2.57 (s, 6H, N(CH3)2), 1.29 (s, 9H, Cp-

Me(vinyl)Si(3-tBu-C5H3)(C5H4)ZrCl2. 727.2 mg (1.676 mmol) of Me(vinyl)Si(3-tBu-

C5H3)(C5H4)Zr(NMe2)2 was weighed into a 20 mL vial in the glove box and dissolved in

10 mL of benzene. 1.1 mL (8.6 mmol, 2.6 equiv) of Me3SiCl was added dropwise and the

vial was closed and allowed to stir for 5.5 hours. All volatiles were removed under vacuum to give a brown goop. The mixture was taken up in petroleum ether, filtered and pumped down to yield 645.6 mg (93 % yield) of a beige powder. 1H NMR revealed a 1:1 mixture of the two diastereomers. 1H NMR (300 MHz, benzene-d6) δ 6.85 (m, 4H, Cp-H), 6.69 (m,

1H, Cp-H), 6.63 (m, 1H, Cp-H), 5.98 (m, 7H, =CH-), 5.82 (dd, J = 3, 2 Hz, 1H, Cp-H), 5.78 (m, 2H, Cp-H), 5.72 (m, 1H, Cp-H), 5.65 (t, J = 3 Hz, 1H, Cp-H), 5.58 (dd, J = 5, 3 Hz, 1H, Cp-H), 5.56 (t, J = 3 Hz, 1H, Cp-H), 5.49 (m, 1H, Cp-H), 1.45 (s, 9H, Cp-CMe3),

1.42 (s, 9H, Cp-CMe3), 0.29 (m, 3H, Si-CH3), 0.16 (m, 3H, Si-CH3).

Me(C2H4B(C6F5)2)Si(3-tBu-C5H3)(C5H4)ZrCl2. 141.1 mg (0.3387 mmol)Me(vinyl)Si(3-

t

Bu-C5H3)(C5H4)ZrCl2 and 118.4 mg (0.3423 mmol, 1.01 equiv) were added to a 50 mL

oven dried round bottom flask and a 180º joint was attached. 20 mL of benzene was vacuum transferred in at –78 ºC. The reaction was allowed to warm to room temperature with stirring to give a brown solution. After 20 minutes everything dissolved to give a yellow solution. The solution was lyophilized to yield 248.8 mg yellow powder (96% yield). 1H NMR yielded a 1:1 mixture of diastereomers. 1H NMR (300 MHz, benzene-d6) δ

6.85 (m, 6H, Cp-H), 6.69 (dd, J = 5, 3 Hz, 2H, Cp-H), 6.61 (dd, J = 5, 3 Hz, 2H, Cp-H), 5.87 (dd, J = 5, 2 Hz, 3H, Cp-H), 5.79 (m, 2H, Cp-H), 5.64 (m, 2H, Cp-H), 5.56 (d, J = 3 Hz, 3H, Cp-H), 5.44 (s, 1H, Cp-H), 1.91 (t, J = 9 Hz, 3H, C2H4), 1.44 (d, 18H, Cp-CMe3),

C2H4), 0.38 (s, 3H, SiCH3), 0.22 (s, 2H, SiCH3). 19F NMR (282 MHz, benzene-d6) δ

–130.29 (m, 4F), –145.85 (t, J = 20 Hz, 1F), –146.13 (t, J = 22 Hz, 1F), –160.54 (m, 4F).

Me(C4H8B(C6F5)2)C(C5H4)(fluorenyl)ZrCl2. 53.0 mg (0.112 mmol) of Me(3-butenyl)-

C(C5H4)(fluorenyl)ZrCl2 was weighed into a 20 mL scintillation vial. 38.8 mg (0.112

mmol) of HB(C6F5)2 was weighed into a separate 1 dram vial. 4 mL of toluene was added

to the HB(C6F5)2 to yield a colorless slurry. The HB(C6F5)2 slurry was added to the

zirconocene. Upon stirring everything dissolved to give an orange solution without much visible color change from the starting zirconocene. After stirring for 30 minutes the toluene was removed under vacuum to give an orange oil. The oil was redissolved in ~ 1 mL toluene and pentane was added to precipitate the product as a 31.4 mg (34% yield) of pale orange powder. More product could be obtained by pumping down the filtrate and lyophilizing to afford an additional 32.9 mg (70 % total yield). 1H NMR (500 MHz, benzene-d6) δ 7.81 (dd, 3JHH = 10, 9 Hz, 2H, Ar-H), 7.44 (d, 3JHH = 9 Hz, 1H, Ar-H), 7.33

(m, 3H, Ar-H), 7.06 (m, 2H, Ar-H), 6.11 (m, 2H, Cp-H), 5.42 (dd, 3JHH = 5, 3 Hz, 1H, Cp-H), 5.34 (dd, 3JHH = 5, 3 Hz, 1H, CH2), 2.77 (m, 1H, CH2), 1.91 (m, 5H, CH2 & CH3),

1.67 (m, 6H, CH2). 19F NMR (282 MHz, benzene-d6) δ –130.76 (d, 3JFF = 23 Hz, 4F, p-

C6F5), –146.93 (s, 2F, p-C6F5), –160.81 (td, 3JFF = 25, 10 Hz, 4F, p-C6F5).

B.7References

1. Brintzinger, H. H.; Fischer, D.; Mulhaupt, R.; Rieger, B.; Waymouth, R. M. Angew.

Chem.-Int. Edit. Engl.,1995, 34, 1143.

2. Coates, G. W. Chem. Rev.,2000, 100, 1223.

4. Resconi, L.; Cavallo, L.; Fait, A.; Piemontesi, F. Chem. Rev.,2000, 100, 1253.

5. Chen, Y. X.; Metz, M. V.; Li, L. T.; Stern, C. L.; Marks, T. J. J. Am. Chem. Soc.,1998,

120, 6287.

6. Chen, M. C.; Marks, T. J. J. Am. Chem. Soc.,2001, 123, 11803.

7. Zhou, J. M.; Lancaster, S. J.; Walker, D. A.; Beck, S.; Thornton-Pett, M.; Bochmann,

M. J. Am. Chem. Soc.,2001, 123, 223.

8. Landis, C. R.; Rosaaen, K. A.; Uddin, J. J. Am. Chem. Soc.,2002, 124, 12062. 9. Wilmes, G. M.; Polse, J. L.; Waymouth, R. M. Macromolecules,2002, 35, 6766. 10. Mohammed, M.; Nele, M.; Al-Humydi, A.; Xin, S. X.; Stapleton, R. A.; Collins, S. J.

Am. Chem. Soc.,2003, 125, 7930.

11. Chen, M. C.; Roberts, J. A. S.; Marks, T. J. J. Am. Chem. Soc.,2004, 126, 4605.

12. Rodriguez-Delgado, A.; Hannant, M. D.; Lancaster, S. J.; Bochmann, M. Macromol.

Chem. Phys.,2004, 205, 334.

13. Song, F. Q.; Hannant, M. D.; Cannon, R. D.; Bochmann, M. Macromol. Symp.,2004,

213, 173.

14. Al-Humydi, A.; Garrison, J. C.; Youngs, W. J.; Collins, S. Organometallics,2005, 24, 193.

15. Stahl, N. G.; Salata, M. R.; Marks, T. J. J. Am. Chem. Soc.,2005, 127, 10898. 16. Bochmann, M.; Cannon, R. D.; Song, F. Kinet. Catal.,2006, 47, 160.

17. Wilson, P. A.; Hannant, M. H.; Wright, J. A.; Cannon, R. D.; Bochmann, M.

Macromol. Symp.,2006, 236, 100.

18. Lanza, G.; Fragalà, I. L.; Marks, T. J. J. Am. Chem. Soc.,1998, 120, 8257. 19. Lanza, G.; Fragalà, I. L.; Marks, T. J. J. Am. Chem. Soc.,2000, 122, 12764.

20. Vanka, K.; Chan, M. S. W.; Pye, C. C.; Ziegler, T. Organometallics,2000, 19, 1841. 21. Nifant'ev, I. E.; Ustynyuk, L. Y.; Laikov, D. N. Organometallics,2001, 20, 5375. 22. Lanza, G.; Fragalà, I. L.; Marks, T. J. Organometallics,2002, 21, 5594.

23. Xu, Z. T.; Vanka, K.; Firman, T.; Michalak, A.; Zurek, E.; Zhu, C. B.; Ziegler, T.

Organometallics,2002, 21, 2444.

24. Zurek, E.; Ziegler, T. Faraday Discuss.,2003, 124, 93.

26. Silanes, M.; Ugalde, J. M. Organometallics,2005, 24, 3233. 27. Vanka, K.; Xu, Z.; Seth, M.; Ziegler, T. Top. Catal.,2005, 34, 143. 28. Ziegler, T.; Vanka, K.; Xu, Z. T. C. R. Chim.,2005, 8, 1552.

29. Martinez, S.; Ramos, J.; Cruz, V. L.; Martinez-Salazar, J. Polymer,2006, 47, 883. 30. Tomasi, S.; Razavi, A.; Ziegler, T. Organometallics,2007, 26, 2024.

31. Aldridge, S.; Bresner, C. Coordin. Chem. Rev.,2003, 244, 71. 32. Piers, W. E. Chem.-Eur. J.,1998, 4, 13.

33. Piers, W. E.; Sun, Y. M.; Lee, L. W. M. Top. Catal.,1999, 7, 133. 34. Mise, T.; Miya, S.; Yamazaki, H. Chem. Lett.,1989, 1853.

35. Schofer, S. J. PhD Thesis, California Institute of Technology, Pasadena, CA, 2004. 36. Zhong, H. A. PhD Thesis, California Institute of Technology, Pasadena, CA, 2001. 37. Ewen, J. A.; Jones, R. L.; Razavi, A.; Ferrara, J. D. J. Am. Chem. Soc., 1988, 110,

6255.

38. Diamond, G. M.; Rodewald, S.; Jordan, R. F. Organometallics,1995, 14, 5. 39. Diamond, G. M.; Jordan, R. F.; Petersen, J. L. J. Am. Chem. Soc.,1996, 118, 8024. 40. Diamond, G. M.; Jordan, R. F.; Petersen, J. L. Organometallics,1996, 15, 4045. 41. Diamond, G. M.; Jordan, R. F.; Petersen, J. L. Organometallics,1996, 15, 4030.

42. Christopher, J. N.; Diamond, G. M.; Jordan, R. F.; Petersen, J. L. Organometallics,

1996, 15, 4038.

43. Peifer, B.; Milius, W.; Alt, H. G. J. Organomet. Chem.,1998, 553, 205.

44. Kneale, B.; Boone, J. E.; Diefenbach, S. P.; Loechelt, C. P.; Prindle, J., J. C. Patent WO0198381, 2001.

45. Kneale, B.; Boone, J. E.; Diefenbach, S. P.; Loechelt, C. P.; Prindle, J., J. C. Patent US6677265, 2004.

46. Yang, Q.; Jensen, M. D.; McDaniel, M. P. Macromolecules,2010, 43, 8836.

47. Jensen, M. D.; Martin, J. L.; Yang, Q.; Thorn, M. G.; McDaniel, M. P.; Rolfing, D. C.; Sukhadia, A. M.; Yu, Y.; Lanier, J. T. Patent US20050288461, 2005.

48. Jensen, M. D.; Martin, J. L.; McDaniel, M. P.; Rolfing, D. C.; Yang, Q.; Thorn, M. G.; Sukhadia, A. M.; Yu, Y.; Lanier, J. T. Patent US20050288462, 2005.

49. Jensen, M. D.; Martin, J. L.; McDaniel, M. P.; Rholfing, D. C.; Yang, Q.; Thorn, M. G.; Sukhadia, A. M.; Yu, Y.; Lanier, J. T. Patent US7148298, 2006.

50. Kestel-Jakob, A.; Alt, H. G. Z. Naturforsch., B: Chem. Sci.,2007, 62, 314.

51. Parks, D. J.; Spence, R. E. V. H.; Piers, W. E. Angew. Chem.-Int. Edit. Engl.,1995, 34, 809.

APPENDIX C