Unusual Reactivity of Methylphosphaalkyne (PCMe) toward Digermenes and Distannenes: Stepwise Formations of Bridged 2,3,5,6-Tetraphospha-1,4-dimethylidenecyclohexanes

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• 作者：Cameron Jones ; Christian Schulten ; Andreas Stasch
• 刊名：Inorganic Chemistry
• 出版年：2008
• 出版时间：February 18, 2008
• 年：2008
• 卷：47
• 期：4
• 页码：1273 - 1278
• 全文大小：163K
• 年卷期：v.47,no.4(February 18, 2008)
• ISSN：1520-510X

文摘

Reactions of methylphosphaalkyne, Prc="http://pubs.acs.org/images/entities/tbd1.gif">CMe, with a digermene, R″₂Gerc="http://pubs.acs.org/images/entities/tbd1.gif">GeR″₂ (R″ = −CH(SiMe₃)₂), and two distannenes, R″₂Snrc="http://pubs.acs.org/images/entities/tbd1.gif">SnR″₂ and Ar′₂Snrc="http://pubs.acs.org/images/entities/tbd1.gif">SnAr′₂ (Ar′ = C₆H₂Prⁱ₃-2,4,6), have given moderate to high yields of the first bridged 2,3,5,6-tetraphospha-1,4-dimethylidenecyclohexanes, [R₂E{C(Me)(H)PC(rc="http://pubs.acs.org/images/entities/tbd1.gif">CH₂)P}]₂ (R = R″ or Ar′, E = Sn or Ge), all of which have been structurally characterized. Their mechanisms of formation are thought to involve successive [2 + 1] and [2 + 2] phosphaalkyne cycloaddition, heterocycle rearrangement, phosphaalkene/vinylphosphine tautomerization, and intermolecular hydrophosphination reactions. In one reaction, two intermediates have been spectroscopically observed and one trapped by coordination to one or two W(CO)₅ fragments, yielding the first diphosphagermole complexes, {[W(CO)₅}_1or2{R″₂Ge[C(Me)PC(Me)P]}], which have been structurally characterized. Differences between the reactivities of Prc="http://pubs.acs.org/images/entities/tbd1.gif">CMe and Prc="http://pubs.acs.org/images/entities/tbd1.gif">CBu^t are highlighted.