Computational Study of Multiple Pathways and Ion-Pairing in Oxidative Addition of Iodomethane to a Binuclear Organoplatinum(II) Complex containing Imine and Phosphine Bridging Ligands

Document Type : Research Paper

Authors

1 School o Natural Sciences – Chemistry, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001, Australia

2 Department of Chemistry, College of Sciences, Shiraz University, Shiraz 71454, Iran

Abstract

A density functional theory (DFT) study of the reaction of [Me2Pt(µ-NN)(µ-dppm)PtMe2] (1) (NN = phthalazine, dppm = bis(diphenylphosphino)methane) with two equivalents of iodomethane in acetone (A) and benzene (B) reveals a mechanism in agreement with spectrocopic and kinetic data reported earlier by Rashidi and coworkers, for which computation permits additional insights. Following initial oxidation at one platinum(II) centre to form mixed valence outer-sphere ion-pairs containing a PtII→PtIV interaction, [Me3Pt(+)(µ-NN)(µ-dppm)PtMe2·I(-)] (6A, 7B), two competing mechanisms are found for the second oxidative addition at the remaining platinum(II) centre. In one mechanism (Path I), a rearrangement of intermediate 6A and 7B to form [Me3Pt(κ1-NN)(µ-dppm)(µ-I)PtMe2] (2aA, 2aB) occurs prior to oxidative addition giving, after subsequent steps, outer-sphere ion-pairs [Me3Pt(κ1-NN)(µ-dppm)(µ-I)PtMe3(+)·I(-)] (10A, 10B), followed by dissociation of phthalazine and formation of the product complex [Me3Pt(µ-dppm)(µ-I)2PtMe3] (4A, 4B) containing two PtIV centres.. In the other mechanism (Path 1I), oxidative addition occurs at the PtII centre of 7A and 7B, leading also to 10A and 10B. Paths I and II are competitive in acetone, but Path I is preferred in benzene. The first oxidative addition computes as having a lower barrier than the second, in accord with  experiment, and we attribute this to the occurrence of a Pta···Ptb interaction assisting the first oxidative addition at Ptb.

Graphical Abstract

Computational Study of Multiple Pathways and Ion-Pairing in Oxidative Addition of Iodomethane to a Binuclear Organoplatinum(II) Complex containing Imine and Phosphine Bridging Ligands

Keywords


  1. Reviews: (a) K. Matsumoto, M. Ochiai, Coord. Chem. Rev. 2004, 232, 229. (b) K. Osakada, Comprehensive Organometallic Chemistry III, 2007, vol. 8, Ch. 8.08. (c) M. Crespo, M. Martinez, S. M. Nabavizadeh, M. Rashidi, Coord. Chem. Rev. 2014, 279, 115. (d) R. B. Aghakhanpour, S. Pazireh, S. M. Nabavizadeh, S. J. Hosseini, F. Niramood Hosseini, J. Iran Chem. Soc. 2020, 17, 2683.
  2. (a) S. Jamali, S. M. Nabavizadeh, M. Rashidi, Inorg. Chem. 2005, 44, 8594. (b) S. Jamali, S. M. Nabavizadeh, M. Rashidi, Inorg. Chem. 2008, 47, 5441. (c) S. J. Hosseini, S. M. Nabavizadeh, S. Jamali, M. Rashidi, Eur. J. Inorg. Chem. 2008, 5099. (d) S. M. Nabavizadeh, H. Molace, E. Haddadi, F. Niroomand Hosseini, S. J. Hoseini, M. M. Abu-Omar, Dalton. Trans. 2021, 50, 15015.
  3. (a) F. N. Hosseini, Polyhedron, 2015, 100, 67. (b) E. Haddadi, S. M. Nabavizadeh, F. N. Hosseini, Polyhedron, 2019, 164, 35. (c) R. B. Aghakhanpour, M. Rashidi, F. Niroomand Hosseini, F. Raoof, S. M. Nabavizadeh, RSC Adv. 2015, 5, 66534.
  4. A. Bondi, J. Phys. Chem. 1964, 68, 441.
  5. M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A. Robb, J. R. Cheeseman, G. Scalmani, V. Barone, G. A. Petersson, H. Nakatsuji, X. Li, M. Caricato, A. V. Marenich, J. Bloino, B. G. Janesko, R. Gomperts, B. Mennucci, H. P. Hratchian, J. V.Ortiz, A. F. Izmaylov, J. L. Sonnenberg, D. Williams-Young, F. Ding, F. Lipparini, F. Egidi, J. Goings, B. Peng, A. Petrone, T. Henderson, D. Ranasinghe, V. G. Zakrzewski, J. Gao, N. Rega, G. Zheng, W. Liang, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, T. Vreven, K. Throssell, J. A. Montgomery, J. E. Peralta, F. Ogliaro, M. J. Bearpark, J. J. Heyd, E. N. Brothers, K. N. Kudin, V. N. Staroverov, T. A. Keith, R. Kobayashi, J. Normand, K. Raghavachari, A. P. Rendell, J. C. Burant, S. S. Iyengar, J. Tomasi, M. Cossi, J. M. Millam, M. Klene, C. Adamo, R. Cammi, J. W. Ochterski, R. L. Martin, K. Morokuma, O. Farkas, J. B. Foresman, D. J. Fox, Gaussian 16, Revision A.03, Gaussian, Inc., Wallingford CT, 2016.
  6. (a) Y. Zhao, D. G. Truhlar, J. Chem. Phys. 2006, 125, 194101. (b) Y. Zhao, D. G. Truhlar, Acc. Chem. Res. 2008, 41, 157.
  7. A. V. Marenich, C. T. Cramer, D. G. Truhlar, J. Phys. Chem. B. 2009, 113, 6378.
  8. A. Bergner, M. Dolg, W. Küchle, H. Stoll, H. Preuß, Mol. Phys. 1993, 80, 1431.
  9. Y. Zhao, D. G. Truhlar, Theor. Chem. Acc. 2008, 120, 215.
  10. (a) S. Ehrlich, J. Moellmann, S. Grimme, Acc. Chem. Res. 2013, 46, 916. (b) J. Antony, R. Sure, S. Grimme, Chem. Commun. 2015, 51, 1764.
  11. F. Weigend, F. Furche, R. Ahlrichs, J. Chem. Phys. 2003, 119, 12753.
  12. (a) C. P. Kelly, C. J. Cramer, D. G. Truhlar, J. Phys. Chem. B 2006, 110, 16066. (b) C. P. Kelly, C. J. Cramer, D. G. Truhlar, J. Phys. Chem. B 2007, 111, 408.
Volume 6, Issue 1
Spring and Summer; Special Issue: In Memory of Prof. Mehdi Rashidi
2022
Pages 93-97
  • Receive Date: 29 July 2022
  • Accept Date: 25 September 2022