Phosphaazaallene Dimerization and Phosphaallene Isomerization: Catalysis by Zerovalent Palladium and Platinum Complexes
作者:Marie-Anne David、John B. Alexander、David S. Glueck、Glenn P. A. Yap、Louise M. Liable-Sands、Arnold L. Rheingold
DOI:10.1021/om960782y
日期:1997.2.1
Several Pd(0) complexes catalyze the dimerization of Mes*PCNPh [2, Mes* = 2,4,6-(t-Bu)3C6H2] to the unsymmetrical heterocycle Mes*P(μ-CNPh)NPh(μ-CPMes*) (5). The symmetrical dimer [Mes*P(μ-CNPh)]2 (7), which forms slowly by uncatalyzed dimerization of 2, does not interconvert with 5; both 5 and 7 were structurally characterized by X-ray crystallography. The Pt complexes PtL2[η2-(P,C)-Mes*PCNPh] [8
A Base-Free Terminal Actinide Phosphinidene Metallocene: Synthesis, Structure, Reactivity, and Computational Studies
作者:Congcong Zhang、Guohua Hou、Guofu Zi、Wanjian Ding、Marc D. Walter
DOI:10.1021/jacs.8b09746
日期:2018.10.31
The synthesis, structure, and reactivity of a base-free terminal actinide phosphinidene metallocene have been comprehensively studied. The salt metathesis reaction of the thorium methyl iodide complex Cp‴2Th(I)Me (2; Cp‴ = η5-1,2,4-(Me3C)3C5H2) with Mes*PHK (Mes* = 2,4,6-(Me3C)3C6H2) in THF furnishes the first stable base-free terminal phosphinidene actinide metallocene, Cp‴2Th═PMes* (3). Density functional
Some sterically protected 1-aza-3-phosphaallenes carrying 2,4,6-tri-t-butylphenyl group were prepared and the hydrolysis reactions of these azaphosphaallenes were studied.
Rhodium-Mediated Stoichiometric P:C Bond Cleavage and Catalytic Isomerization in Phosphacumulenes
作者:Marie-Anne David、Sara N. Paisner、David S. Glueck
DOI:10.1021/om00001a007
日期:1995.1
Reaction of Rh(PCy(3))(2)Cl (4a, Cy = cyclo-C6H11 with the phosphacumulenes Mes*P=C=X (X = O (1) X = NPh (2); Mes* = 2,4,6-(t-Bu)(3)C6H2) results in P=C bond cleavage to form [2,4-(t-Bu)(2)C6H2(6-CMe(2)CH(2)PH)](5) and trans-Rh(PCy(3))(2)Cl(CX) (6, X = O; 7,X = NPh), respectively. In contrast, 4a and related Rh(I) PPh(3) complexes are catalyst precursors for the rearrangement of Mes*P=C=CPh(2) 13) to its isomer [2,4-(t-Bu)(2)C6H2(6-CMe(2)CH(2)PCH=CPh(2))] (8); the intermediate [Rh(PCy(3))[eta(2)(P,C)-Mes*P=C=CPh(2)]Cl](n) (9a), which is itself an active catalyst for the isomerization, was isolated and characterized spectroscopically.
Phosphinidene Transfer Reactions of the Terminal Phosphinidene Complex Cp2Zr(:PC6H2-2,4,6-t-Bu3)(PMe3)
作者:Tricia L. Breen、Douglas W. Stephan
DOI:10.1021/ja00153a013
日期:1995.12
The terminal zirconium phosphinidene complex Cp(2)Zr(PR*)(PMe(3)) (R* = C6H2-2,4,6-t-Bu(3)) 2 has been synthesized in high yield, and its reactivity has been investigated. The compound Cp(2)ZrMe(PHR*) 1 is unstable with respect to the loss of methane; in the presence of PMe(3) this reaction yielded 2. Reactions of 2 with benzophenone, benzaldehyde, or isophthalaldehyde produced phosphaalkenes PhCH=PR* 3, Ph(2)C=PR* 4, and 1,3-C6H2(CH=PR*)(2) 5, respectively. PhN=C=PR* 6 resulted from the reaction of 2 with phenyl isothiocyanate while the use of cyclohexanone afforded the enolate Cp(2)Zr(PHR*)(OC6H9) 7. Phosphinidene group transfer also took place in reactions of 2 with the appropriate organic dihalide or epoxide. In this way phosphaalkenes CH2=PR* 8 and CHCl=PR* 9, phosphirane (CH(2)CH(2)PR*) 10, phospholane 1,2-C6H4(CH(2)PR*)(2) 11 and substituted phosphiranes (CH2CH)(CHCH2-PR*) 12, CH2C(CCH(2)PR*) 13, (PhCHCH(Ph)PR*) 15, and trans-(PhCHCH(2)PR*) 16 were synthesized. The use of propylene oxide yielded the enolate Cp(2)Zr(PHR*)(OCH2CH=CH2) 17. Similar reactions of 2 with heavier group 14 dihalides and sulfides furnished Cp(2)Zr(PR*(SiMe(2)Cl))Cl 18, PR*(SiMe(2)Cl)(2) 19, (Me(2)GeCl)(2) PR* 20, (Me(2)GePR*)(2) 21, (t-Bu(2)SnPR*)(2) 22, and (Me(2)SnPR*)(2) 23. Intramolecular phosphinidene transfer occurred in reactions of 2 with benzonitrile and dicyclohexylcarbodiimide, giving Cp(2)Zr(PMe(3))(NC(Ph)(PR*)) 25 and Cp(2)Zr(N(Cy))(2)C=PR* 26, respectively. Crystallographic data are reported for compounds 22, 25b, and 26.