1 / 23

Reactivity of bridging Pentelidene Complexes

Reactivity of bridging Pentelidene Complexes. Contents:. Overview on phosphinidene complexes General reactivity pattern Reactivity towards diphosphenes Reactivity towards primary phosphines. Phosphinidene complexes :.  1. µ 2. µ 3. µ 4. M. Ruiz, A. J. Carty.

sela
Télécharger la présentation

Reactivity of bridging Pentelidene Complexes

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ReactivityofbridgingPentelideneComplexes

  2. Contents: • Overview on phosphinidene complexes • General reactivity pattern • Reactivity towards diphosphenes • Reactivity towards primary phosphines

  3. Phosphinidenecomplexes: 1 µ2 µ3 µ4 M. Ruiz, A. J. Carty G. Huttner et al, Acc. Chem. Res. 1986, 19, 406-413 M. F. Lappert 1979 A. H. Cowley 1990 stablecompoundswithbulkysubstituents R orbulkyligands Cowley, Lappert, Wolczanski, Schrock, Hey-Hawkins intermediates withlessbulkysubstituents R Mathey, Lammertsma, Streubel

  4. Preparation: 31P: δ= 1076 ppm (s,1JWP = 166 Hz,187 Hz) Jutziet al., J. Organomet. Chem.1990, 390, 317-322.

  5. sp2-hybridisation at the phosphorus atom • phosphinidene as m2-4e--ligand • p-back bonding from the metal to the P atom a3-centre-4p-electron system Bondsituation: LUMO -4.28eV HOMO -5.45eV

  6. Reactivitypattern: Cp* migration Cp* shift Cp* ring expansion Cp* elimination nucleophilicattack

  7. Thermolysis: Scheer et al., Chem. Eur. J.1998, 4, 1917-1923.

  8. Photolysis: Scheer et al., Eur. J. Inorg. Chem.2001, 1661-1663.

  9. Photolysiswithdiphosphenes: P1 P1 P1 P1` P2 As1 d(P1-As1) = 2.216(1) Å d(P1-P2) = 2.1122(10) Å M. Scheer, C. Kuntz, M. Stubenhofer, M. Linseis, R.Winter, M. Sierka,Angew. Chem. Int. Ed. 2009, 48, 2600 –2604.

  10. Photolysiswithdiphosphenes: P2 As1 P3 P1 P1 P2 H1 H1 d(P1-P2) = 2.187(3) Å d(P2-P3) = 2.075(3)Å d(P1-As1) = 2.179(2) Å d(P2-As1) = 2.298(2)Å radical: d(P1-P2) = 2.1122(10) Å radical: d(P1-As1) = 2.216(1) Å

  11. Cyclovoltammogram: E½ (Ox.) = 0.17 V E½ (Ox.) = 0.17 V E½ (Red.) = –0.81 V E½ (Red.) = –0.81 V rate ofspeed: 100 mV/s

  12. Oxidation andreduction: P3 P1 P1 P2 P2 As1 bondlength: d(P1-P2) = 2.070 (3) Å d(P2-P3) = 2.065 (3) Å bondlength: d(P1-As1) = 2.186(3) Å d(P2-As1) = 2.191(2) Å

  13. Oxidation andreduction: P2 P3 P1 bondlength: d(P1-P2) = 2.256 (7) Å d(P2-P3) = 2.085 (6) Å

  14. Summary: M. Stubenhofer, C. Kuntz, M. Bodensteiner, U. Zenneck, M. Sierka, M. Scheer Chem. Eur. J.2010, 13, 1745-1747 .

  15. Reactivitytowardsprimaryphosphines: N1 N1 P2 B1 P1 R = H2P-BH2NMe3 B1 P1 As1 d(P1-P2) = 2.237(2) Å d(As1-P1) = 2.352(3) Å M. Scheer, C. Kuntz, M. Stubenhofer, M. Zabel, A. Y. Timoshkin, Angew. Chem. Int. Ed. 2010, 49, 188 –192.

  16. Reactivitytowardsprimaryphosphines: R = Ph P1 P2 d(P1-P2) = 2.197(1) Å M. Scheer, C. Kuntz, M. Stubenhofer, M. Zabel, A. Y. Timoshkin, Angew. Chem. Int. Ed. 2010, 49, 188 –192.

  17. Reactivitytowardsprimaryphosphines: R = Ph M. Scheer, C. Kuntz, M. Stubenhofer, M. Zabel, A. Y. Timoshkin, Angew. Chem. Int. Ed. 2010, 49, 188 –192.

  18. Reactivitytowardsprimaryphosphines: P1 H1 P2 d(P1-P2) = 2.239(2) Å DFT-methods (B3LYP/6-31G* (ECP for W)) M. Scheer, C. Kuntz, M. Stubenhofer, M. Zabel, A. Y. Timoshkin, Angew. Chem. Int. Ed. 2010, 49, 188 –192.

  19. Reactivity towards primaryphosphines: R =tBu M. Scheer, C. Kuntz, M. Stubenhofer, M. Zabel, A. Y. Timoshkin, Angew. Chem. Int. Ed. 2010, 49, 188 –192.

  20. Reactivitytowardsprimaryphosphines: As1 P3 P2 P1 P1 P2 d(P1-As1) = 2.334(3) Å d(As1-P2) = 2.369(3) Å 31P{1H}-NMR: symd = -17.2 ppm asymd = -20.8 ppm (d, 2JP,P = 3Hz) d = -18.7 ppm (d, 2JP,P = 3Hz) d(P1-P2) = 2.215 (2) Å d(P2-P3) = 2.238(2) Å 31P{1H}-NMR: d= -90.7 ppm (dd, 1JP,P = 197 Hz d = -13.4 ppm (d, 1JP,P = 197 Hz)

  21. Reactivitytowardsprimaryphosphines:

  22. M. Stubenhofer, C. Kuntz, G.Balázs, M. Zabel, M. Scheer, Chem. Commun. 2009, 13, 1745 – 1747.

  23. Acknowledgement: • Prof. Manfred Scheer • Scheer Group • DFG

More Related