Facile Synthesis of Pentacarbonyltungsten(0) Complexes with Oxaphosphirane Ligands
作者:Rainer Streubel、Maren Bode、Janaina Marinas Pérez、Gregor Schnakenburg、Jörg Daniels、Martin Nieger、Peter G. Jones
DOI:10.1002/zaac.200900063
日期:2009.7
Facilesynthesis of tungsten(0) complexes of the type 7a–g (R1 = C5Me5) and 8a–g (R1 = CH(SiMe3)2) using transient Li/Cl phosphanylidenoid tungsten(0) complexes 4, 5 and carbonyl derivatives 6a–g is reported; furthermore, for all complexes NMR, IR spectroscopic, mass spectrometric investigations and, in addition, single-crystal X-ray structures of complexes 7b,d–g and 8b,d are presented.
Protonation-Induced Rearrangement of an Oxaphosphirane Complex
作者:Janaina Marinas Pérez、Holger Helten、Bruno Donnadieu、Christopher A. Reed、Rainer Streubel
DOI:10.1002/anie.200906825
日期:2010.3.29
O‐Protonation of an oxaphosphirane tungsten complex causes ring opening and the formation of a POH functional methylene phosphonium ligand bound side‐on to the tungsten center (see scheme).
O-Protonation and ring cleavage of oxaphosphirane complexes 1a,b enabled the synthesis of novel compounds such as the bicyclic 1,3-oxaphospholane complex 5 and the eta(2)-Wittig ylide complex 7, which demonstrate the emerging chemistry of this new reactive intermediate. Whereas P-O bond cleavage occurred, in the first case, thus revealing the superior ability of the P-bonded Cp* group to stabilize
cycloaddition reactions, P−C single bonds are inert in this respect. Herein, reactions of oxaphosphirane complexes with tetrachloro‐ortho‐benzoquinone are presented that reveal a stereoselective reaction of the endocyclic P−C bond to afford benzo‐1,3,6,2‐trioxaphosphepine complexes. High‐level DFT calculations provide evidence that the final product is derived from a sequence of three consecutive steps
尽管已知磷烯烃和膦参与[4+ n ]环加成反应,但在这方面,PC单键是惰性的。本文介绍了氧杂磷杂环丙烷配合物与四氯邻苯二醌的反应,揭示了内环P-C键的立体选择性反应,从而得到了苯并1,3,6,2-三氧杂磷杂环丙烷配合物。高水平的DFT计算提供了证据,表明最终产品是从涉及对位范德华复合物的三个连续步骤的序列中得出的。
Strong Evidence for a Transient Phosphinidenoid Complex
作者:Aysel Özbolat、Gerd von Frantzius、Janaina Marinas Pérez、Martin Nieger、Rainer Streubel