title: Reaction of "non-symmetrical" 1,2,4-trithiolanes with [(phosphane)Pt(0)(η2-nbe)] complexes.
abstract: Two unsymmetrical 1,2,4-trithiolanes (1d and 1e) were reacted with [Pt(0)(PPh(3))(2)(η(2)-nbe)] (6; nbe=norborn-2-ene) and [Pt(0)(dppn)(η(2)-nbe)] (11; dppn=1,8-bis(diphenylphosphanyl)naphthalene)), respectively. Their treatment with compound 6 resulted in the formation of six-membered platinacycles of type 7, which selectively underwent fragmentation into dithiolato complexes and thiobenzophenone (4b). The isolation of the first stable C-substituted member of this class of compounds (i.e., compound 7e) permitted kinetic studies of this process by using UV/Vis spectroscopy. These results, together with DFT calculations, allowed us to propose a mechanism for the reactions of compound 6 with 1,2,4-trithiolanes. In contrast, similar treatment of compound 11 with compounds 1d and 1e at room temperature did not result in any reaction. Heating the appropriate samples to 110 °C led to the formation of dithiolato complexes and η(2)-thioketone compounds, thus pointing to a thermally induced [3+2]-cycloreversion of the heterocycles as an initial step of the reaction.
authors.affiliation: Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstrasse 8, 07743 Jena, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Weisheit
authors.forename: Antje
authors.initials: A
authors.lastname: Kriltz
authors.forename: Helmar
authors.initials: H
authors.lastname: Görls
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Mlostoń
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Imhof
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Weigand