Li/X phosphinidenoid pentacarbonylmetal complexes: a combined experimental and theoretical study on structures and spectroscopic properties.
Li/X phosphinidenoid pentacarbonylmetal complexes: a combined experimental and theoretical study on structures and spectroscopic properties.
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Li/X膦类五羰基金属配合物:结构和光谱性质的实验与理论相结合的研究
DOI:
10.1021/ic302786v
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发表时间:
2013
影响因子:
4.6
通讯作者:
D. Gudat
中科院分区:
文献类型:
--
作者:
R. Streubel;A. Özbolat-Schön;G. von Frantzius;H. Lee;J. Daniels;G. Schnakenburg;D. Gudat
The synthesis ofP-F phosphane metal complexes [(CO)5M{RP(H)F}]2a–c(R = CH(SiMe3)2;a: M = W;b: M = Mo;c: M = Cr) is described using AgBF4for a Cl/F exchange inP-Cl precursor complexes [(CO)5M{RP(H)Cl}]3a–c; thermal reaction of 2H-azaphosphirene metal complexes [(CO)5M{RP(C(Ph)N}]1a–cwith [Et3NH]X led to complexes3a–c,4, and5(M = W;a–c: X = Cl;4: X = Br;5: X = I). Complexes2a–c,3a–c,4, and5were deprotonated using lithium diisopropylamide in the presence of 12-crown-4 thus yielding Li/X phosphinidenoid metal complexes [Li(12-crown-4)(Et2O)n][(CO)5M(RPX)]6a–c,7a–c,8, and9(6a–c: M = W, Mo, Cr; X = F;7a–c: M = W, Mo, Cr; X = Cl;8: M = W; X = Br;9: M = W; X = I). This first comprehensive study on the synthesis of the title compounds reveals metal and halogen dependencies of NMR parameters as well as thermal stabilities of6a,7a,8, and9in solution (F > Cl > Br > I). DOSY NMR experiments on the Li/F phosphinidenoid metal complexes (6a–c; M = W, Mo, Cr) rule out that the cation and anion fragments are part of a persistent molecular complex or tight ion pair (in solution). The X-ray structure of6areveals a salt-like structure of [Li(12-crown-4)Et2O][(CO)5W{P(CH(SiMe3)2)F}] with long P–F and P–W bond distances compared to2a. Density functional theory (DFT) calculations provide additional insight into structures and energetics of cation-free halophosphanido chromium and tungsten complexes and four contact ion pairs of Li/X phosphinidenoid model complexes [Li(12-crown-4)][(CO)5M{P(R)X}] (A-D) that represent principal coordination modes. The significant increase of the compliance constant of the P–F bond in the anionic complex [(CO)5W{P(Me)F}] (10a) revealed that a formal lone pair at phosphorus weakens the P–F bond. This effect is further enhanced by coordination of lithium and/or the Li(12-crown-4) countercation (to10a) as in typeA-Dcomplexes. DFT calculated phosphorus NMR chemical shifts allow for a consistent interpretation of NMR properties and provide a preliminary explanation for the “abnormal” NMR shift ofP-Cl derivatives7a–c. Furthermore, calculated compliance constants reveal the degree of P–F bond weakening in Li/F phosphinidenoid complexes, and it was found that a more negative phosphorus–fluorine coupling constant is associated with a larger relaxed force constant.
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DOI:
--
发表时间:
2007
期刊:
影响因子:
--
作者:
Aysel Özbolat;Arif Ali Khan;Gerd von Frantzius;M. Nieger;R. Streubel
通讯作者:
R. Streubel
DOI:
--
发表时间:
2010
期刊:
影响因子:
--
作者:
K. Ǐssleib;H. Schmidt;C. Wirkner
通讯作者:
C. Wirkner
DOI:
--
发表时间:
1990
期刊:
影响因子:
--
作者:
P. Jutzi;Rainer Kroos
通讯作者:
Rainer Kroos
影响因子:
3.3
作者:
C. Wüllen
通讯作者:
C. Wüllen
DOI:
--
发表时间:
1982
期刊:
影响因子:
--
作者:
C. Couret;J. Escudié;J. Satge,
通讯作者:
J. Satge,