Reaction mechanism of transmetalation between tetraorganostannanes and platinum(II) aryltriflate complexes. Mechanistic model for stille couplings
(2006) In Organometallics 25(5). p.1285-1292- Abstract
- The complexes trans-[PtPh(OTf)(PMe2Ph)(2)] (1) and trans- [PtPh(OTf)(PPh3)(2)] (4) were synthesized from the corresponding chloro complexes in moderate yields. Complex I is slowly hydrolyzed in solution, giving the dinuclear hydroxo-bridged complex [Pt(mu-OH)(PMe2Ph)(2)](2)(CF3SO3)(2) (6), which was characterized by X-ray crystallography. In solution I and 4 undergo fast solvolysis to give the corresponding solvento cations. The reactivities of 1 and 4 with Me3SnPh were investigated in different solvents, and with 1 two products, trans- [PtPh2(PMe2Ph)(2)] (8) and cis-[PtPh2(PMe2Ph)(2)] (9), were always formed simultaneously. In THF an intermediate, trans- [PtPhMe(PMe2Ph)(2)] (14), was characterized on the path to 9. The kinetics for these... (More)
- The complexes trans-[PtPh(OTf)(PMe2Ph)(2)] (1) and trans- [PtPh(OTf)(PPh3)(2)] (4) were synthesized from the corresponding chloro complexes in moderate yields. Complex I is slowly hydrolyzed in solution, giving the dinuclear hydroxo-bridged complex [Pt(mu-OH)(PMe2Ph)(2)](2)(CF3SO3)(2) (6), which was characterized by X-ray crystallography. In solution I and 4 undergo fast solvolysis to give the corresponding solvento cations. The reactivities of 1 and 4 with Me3SnPh were investigated in different solvents, and with 1 two products, trans- [PtPh2(PMe2Ph)(2)] (8) and cis-[PtPh2(PMe2Ph)(2)] (9), were always formed simultaneously. In THF an intermediate, trans- [PtPhMe(PMe2Ph)(2)] (14), was characterized on the path to 9. The kinetics for these reactions were evaluated numerically, and on the basis of rate laws, activation parameters, and reactivity trends a mechanism involving parallel equilibria to 8 and 9 with associative activation in all steps is proposed. In this mechanism the initial attack always takes place trans to the phenyl group, giving 8 and 14, respectively, via an open transition state. In a subsequent reaction, 14 reacts with another molecule of stannane, giving 9 as the final product via a cyclic transition state. Complex 4 gives exclusive formation of cis products: cis-[PtPhMe(PPh3)2] (12) and cis-[PtPh2(PPh3)2] (13). These results are discussed in relation to the reaction mechanism of the transmetalation step in the Stille reaction. (Less)
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https://lup.lub.lu.se/record/416671
- author
- Nilsson, Patrik LU ; Puxty, G and Wendt, Ola LU
- organization
- publishing date
- 2006
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Organometallics
- volume
- 25
- issue
- 5
- pages
- 1285 - 1292
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000235691500027
- scopus:33644986119
- ISSN
- 1520-6041
- DOI
- 10.1021/om051021a
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Organic chemistry (S/LTH) (011001240), Department of Chemistry (011001220)
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- 1b623bd5-3f16-4451-94ac-936ed1d2485f (old id 416671)
- date added to LUP
- 2016-04-01 12:36:05
- date last changed
- 2022-01-27 07:17:25
@article{1b623bd5-3f16-4451-94ac-936ed1d2485f, abstract = {{The complexes trans-[PtPh(OTf)(PMe2Ph)(2)] (1) and trans- [PtPh(OTf)(PPh3)(2)] (4) were synthesized from the corresponding chloro complexes in moderate yields. Complex I is slowly hydrolyzed in solution, giving the dinuclear hydroxo-bridged complex [Pt(mu-OH)(PMe2Ph)(2)](2)(CF3SO3)(2) (6), which was characterized by X-ray crystallography. In solution I and 4 undergo fast solvolysis to give the corresponding solvento cations. The reactivities of 1 and 4 with Me3SnPh were investigated in different solvents, and with 1 two products, trans- [PtPh2(PMe2Ph)(2)] (8) and cis-[PtPh2(PMe2Ph)(2)] (9), were always formed simultaneously. In THF an intermediate, trans- [PtPhMe(PMe2Ph)(2)] (14), was characterized on the path to 9. The kinetics for these reactions were evaluated numerically, and on the basis of rate laws, activation parameters, and reactivity trends a mechanism involving parallel equilibria to 8 and 9 with associative activation in all steps is proposed. In this mechanism the initial attack always takes place trans to the phenyl group, giving 8 and 14, respectively, via an open transition state. In a subsequent reaction, 14 reacts with another molecule of stannane, giving 9 as the final product via a cyclic transition state. Complex 4 gives exclusive formation of cis products: cis-[PtPhMe(PPh3)2] (12) and cis-[PtPh2(PPh3)2] (13). These results are discussed in relation to the reaction mechanism of the transmetalation step in the Stille reaction.}}, author = {{Nilsson, Patrik and Puxty, G and Wendt, Ola}}, issn = {{1520-6041}}, language = {{eng}}, number = {{5}}, pages = {{1285--1292}}, publisher = {{The American Chemical Society (ACS)}}, series = {{Organometallics}}, title = {{Reaction mechanism of transmetalation between tetraorganostannanes and platinum(II) aryltriflate complexes. Mechanistic model for stille couplings}}, url = {{http://dx.doi.org/10.1021/om051021a}}, doi = {{10.1021/om051021a}}, volume = {{25}}, year = {{2006}}, }