Diademan und Strukturverwandte, II. Katalysierte Umlagerungen und Hydrierungen

Abstract

Kupfer‐, Silber‐, Gold‐ und Rhodiumverbindungen katalysieren die Umlagerung von Diademan (1) zu Triquinacen (5) bzw. Snouten (7). Zur Erklärung können bekannte Mechanismen herangezogen werden. Die katalytische Hydrierung von 1 führt zu den 6 Produkten 9–14 in einer vom Umsetzungsgrad unabhängigen Zusammensetzung. Adamantan, das thermodynamisch stabilste aller möglichen “Hexahydrodiademane”, konnte nicht nachgewiesen werden.

Preparation and Reactivity of [D3d]‐Octahedrane: The Most Stable (CH)12 Hydrocarbon

“…This is remarkable, since hydrogenolysis of oligocyclic hydrocarbons with more than one cyclopropane moiety does not necessarily occur with thermodynamic control, as had previously been hypothesized, [25] but may be governed by the mode of adsorption on the catalyst surface. [26] Direct functionalizations of several cage hydrocarbons, especially adamantane (12), with electrophilic (bromination, [27] nitroxylation [28] ) or radical (halogenation, [29] oxygenation [30] ) reagents have been studied. Bromination of the structurally related hydrocarbon diamantane 11 occurs at the "belt" C-H position under mild conditions.…”

Thermochemical and X-ray Crystallographic Investigations of Some (CH)10 Hydrocarbons: Basketene, Nenitzescu’s Hydrocarbon, and Snoutene

“…The obtained strain energies and the derived heats of isomerization to 9,10-dihydronaphthalene (7) did not correlate in any way either with the activation energies of the thermal isomerizations of these Families of (CH) n hydrocarbons are characterized by the multiple rearrangements into one another that their members can undergo. [1] These rearrangements can be initiated (CH) 10 hydrocarbons or with the structural features determined experimentally for basketene (9) and computationally (DFT at the B3LYP/6-311+G* level) for snoutene (14). Compounds 8, 9, 10, and 14 exhibited solid-state phase transitions in a narrow temperature range (−55 to −70°C), whereas the melting points or rearrangement temperatures varied to a much greater extent (in the 0−126°C range).…”

“…( Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002) thermally, photochemically, or under metal catalysis conditions. [2] The thermodynamic sink of all interconversions of (CH) 10 hydrocarbons is apparently cis-9,10-dihydronaphthalene (7), which is formed by thermal rearrangement from bullvalene (1), lumibullvalene (2), isobullvalene (3), and isolumibullvalene (4), from bicyclo[4.2.2]decatetraene (5) and its intramolecular DielsϪAlder adduct 6, from pentacyclo-[4.4.0.0 2,5 .0 3,8 .0 4,7 ]dec-9-ene (9, basketene) and tricyclo-[4.2.2.0 2,5 ]deca-3,7,9-triene (8, Nenitzescu's hydrocarbon), from hexacyclo[4.4.0.0 2,4 .0 3,9 .0 5,7 .0 8,10 ]decane (10, diademane) and triquinacene (11), from the syn-and anti-tricyclo[4.4.0.0 2,5 ]decatrienes (12), from all-cis-cyclodecapentaene (13), and from pentacyclo[4.4.0.0 2,4 .0 3,8 .0 5,7 ]dec-9-ene (14, snoutene) (Scheme 1). [1,2] Many of these interconversions do not afford 7 directly.…”

“…Upon heating to 500°C, snoutene (14) undergoes an interesting automerization, detectable by appropriate labelling, which interchanges the two vinylic and the cyclopropyl methyne positions. [7] When irradiated with UV light, snoutene (14) reversibly rearranges to diademane (10). [8] Thermally, [9] and under silver(I), [10] copper(I) [10] or LiCB 11 Me 12…”

A Simple Route tocis- andtrans-Bis-σ-homobenzenes

“…[5] Nevertheless, triquinacene (1) showed its usefulness as a precursor for the synthesis of a variety of hydrocarbons with interesting chemical and structural properties. [5] Diademane (2) proved not to be obtainable by means of an envisaged threefold internal photochemical cycloaddition of triene 1, but de Meijere et al [11,12] developed an independent synthetic route. Thermally labile diademane (2) could be isolated using this route, but at 80°C it quickly transformed into triquinacene (1) through a [σ2sϩσ2sϩσ2s] cycloreversion.…”