title: Evidence for a rapid degenerate hetero-Cope-type rearrangement in [Cp*W(S)2S-CH2-CH=CH2].
abstract: Treatment of the salt [PPh(4)]+[Cp*W(S)3]- (6) with allyl bromide gave the neutral complex [Cp*W(S)2S-CH2-CH=CH2] (7). The product 7 was characterized by an X-ray crystal structure analysis. Complex 7 features dynamic NMR spectra that indicate a rapid allyl automerization process. From the analysis of the temperature-dependent NMR spectra a Gibbs activation energy of DeltaG(not equal) (278 K) approximately 13.7+/-0.1 kcal mol(-1) was obtained [DeltaH(not equal) approximately 10.4+/-0.1 kcal mol(-1); DeltaS(not equal) approximately -11.4 cal mol(-1) K(-1)]. The DFT calculation identified an energetically unfavorable four-membered transition state of the "forbidden" reaction and a favorable six-membered transition state of the "Cope-type" allyl rearrangement process at this transition-metal complex core.
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms Universität Münster, Corrensstraße 40,D-48149 Münster (Germany), Fax: (+49) 251-83-36503.
authors.forename: Florian
authors.initials: F
authors.lastname: Eweiner
authors.affiliation: Department of Chemistry, Faculty of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan).
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Senda
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms Universität Münster, Corrensstraße 40,D-48149 Münster (Germany), Fax: (+49) 251-83-36503.
authors.forename: Klaus
authors.initials: K
authors.lastname: Bergander
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms Universität Münster, Corrensstraße 40,D-48149 Münster (Germany), Fax: (+49) 251-83-36503.
authors.forename: Christian
authors.initials: C
authors.lastname: Mück-Lichtenfeld
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms Universität Münster, Corrensstraße 40,D-48149 Münster (Germany), Fax: (+49) 251-83-36503.
authors.forename: Stefan
authors.initials: S
authors.lastname: Grimme
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms Universität Münster, Corrensstraße 40,D-48149 Münster (Germany), Fax: (+49) 251-83-36503.
authors.forename: Roland
authors.initials: R
authors.lastname: Fröhlich
authors.affiliation: Department of Chemistry, Faculty of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan).
authors.forename: Michiko
authors.initials: M
authors.lastname: Aoyama
authors.affiliation: Department of Chemistry, Faculty of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan).
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kawaguchi
authors.affiliation: Department of Chemistry, Faculty of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan).
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ohki
authors.affiliation: Department of Chemistry, Faculty of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan).
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Matsumoto
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms Universität Münster, Corrensstraße 40,D-48149 Münster (Germany), Fax: (+49) 251-83-36503.
authors.forename: Gerald
authors.initials: G
authors.lastname: Kehr
authors.affiliation: Department of Chemistry, Faculty of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan).
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Tatsumi
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms Universität Münster, Corrensstraße 40,D-48149 Münster (Germany), Fax: (+49) 251-83-36503.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Erker