54006-34-7Relevant articles and documents
Sterically encumbered tin and phosphorus peri-substituted acenaphthenes
Chalmers, Brian A.,Athukorala Arachchige, Kasun S.,Prentis, Joanna K. D.,Knight, Fergus R.,Kilian, Petr,Slawin, Alexandra M. Z.,Woollins, J. Derek
, p. 8795 - 8808 (2014)
A group of sterically encumbered peri-substituted acenaphthenes have been prepared, containing tin moieties at the 5,6-positions in 1-3 ([Acenap(SnR 3)2], Acenap = acenaphthene-5,6-diyl; R3 = Ph3 (1), Me3 (2); [(Acenap)2(SnMe 2)2] (3)) and phosphorus functional groups at the proximal peri-positions in 4 and 5 ([Acenap(PR2)(PiPr 2)] R2 = Ph2 (4), Ph(iPr) (5)). Bis(stannane) structures 1-3 are dominated by repulsive interactions between the bulky tin groups, leading to peri-distances approaching the sum of van der Waals radii. Conversely, the quasi-linear CPh-P...P three-body fragments found in bis(phosphine) 4 suggest the presence of a lp(P)-σ*(P-C) donor-acceptor 3c-4e type interaction, supported by a notably short intramolecular P...P distance and notably large J PP through-space coupling (180 Hz). Severely strained bis(sulfides) 4-S and 5-S, experiencing pronounced in-plane and out-of-plane displacements of the exocyclic peri-bonds, have also been isolated following treatment of 4 and 5 with sulfur. The resulting nonbonded intramolecular P...P distances, ～4.05 A and ～12% longer than twice the van der Waals radii of P (3.60 A), are among the largest ever reported peri-separations, independent of the heteroatoms involved, and comparable to the distance found in 1 containing the larger Sn atoms (4.07 A). In addition we report two metal complexes with square planar [(4)PtCl2] (4-Pt) and octahedral cis-[(4)Mo(CO)4] (4-Mo) geometries. In both complexes the bis(phosphine) backbone is distorted, but notably less so than in bis(sulfide) 4-S. All compounds were fully characterized, and except for bis(phosphine) 5, crystal structures were determined.
Synthesis, crystal structures, and quantum chemical calculations of Novel Phosphonium Salt-1,5-diphospha-3-phosphonia-tricyclo pentane cations
Bani-Fwaz, Mutasem Z.,Fazary, Ahmed E.,Becker, Gerd
supporting information, p. 51 - 65 (2017/06/07)
This work deals with reactions between the kinetically stable 2-tert-butyl-1λ3-phospha-alkyne, tBu-C[tbnd]P, and various halodiorganylphosphines (X = Cl, Br). The isolated ionic salts with the 2,4-di-tert-butyl-3,3-diorganyl-1λ3,5λ3-diphospha-3-phosphonia-tricyclo[2.1.0.02,5]pentane cations, [R2C2tBu2P3]⊕ (R = ethyl, isopropyl, methyl, phenyl), were characterized by spectroscopic methods; additionally, the results of X-ray structure analyses were confirmed by quantum chemical calculations with Gaussian 03 program which were performed on the hydrogen substituted phosphonium and phosphenium cations in order to ascertain optimized structural data and relative energies for different isomers. As for the phosphonium cation ([H2P(CH)2P2]⊕) generated from our work the conventional trigonal bipyramidal framework of point group C2v represents the absolute minimum on the potential energy surface. To our surprise this situation is followed by a second one which has to be attributed to the so-called housene structure of point group C1 showing a somewhat higher energy value + 77.9 kJ/mol. Quite a reverse situation is encountered for the phosphenium cation [P(CH)2P2]⊕. Here the pseudo square-based pyramidal nido structure of point group C2v known from Russell's tetrachloroaluminate(III) compound is found to be the only minimum on the potential energy surface. A phosphenium cation with a trigonal bipyramidal framework of point group C2v is higher in energy by only 35.7 kJ/mol, but due to one imaginary frequency it has to be considered the structure of a transition state. The opened housene structure corresponds neither to a minimum nor to a saddle point on the potential energy surface. In the pseudo square-based pyramidal nido structure (point group C2v) of the phosphenium cation [P(CH)2P2]⊕ the s-orbital and all p-orbitals of the apical four-coordinate phosphorus atom are used to form two P–C and two P–P bonds. Further addition of two hydrogen atoms to entail the phosphonium cation [H2P(CH)2P2]⊕ of point group symmetry C2 not only increases the coordination number of the apical phosphorus atom to six but also requires two electrons and two orbitals for P–H bonding. These are no longer available to the bonding system within the nido structure; as a consequence, its energy increases to +246.6 kJ/mol and the cation rearranges to give the conventional structure of ours.
P-chiral phosphinoselenoic chlorides and phosphinochalcogenoselenoic acid esters: Synthesis, characterisation, and conformational studies
Kimura, Tsutomu,Murai, Toshiaki
, p. 952 - 959 (2007/10/03)
(Chemical Equation Presented) P-Chiral alkyl or aryl phenylphosphinoselenoic chlorides were obtained by reacting PhPCl2 with Grignard reagents and elemental selenium. P-Chiral dialkyl chlorides were also obtained by treating PCl3 with two different Grignard reagents and elemental selenium. The structure of the chloride was determined by X-ray molecular structure analysis. P-Chiral phosphinochalcogenoselenoic acid esters bearing a P=Se double bond were synthesized by treating the chlorides with alkali metal alkoxide and chalcogenolates, whereas those bearing a P-Se single bond were obtained by sequential treatment of the chlorides with sodium hydroxide, sulfide or selenide, and alkyl iodides. X-ray molecular structure analyses of esters showed that they adopted gauche conformations. The computational results supported the observed conformational preference. Natural bond orbital analyses of the model compounds showed that two types of nonbonding orbital interactions, nE′ → σ*P=E and nE → σ*P-E′, are important in these compounds. Linear correlations were observed between the experimental 77Se NMR chemical shifts or the coupling constants of P-Se bonds in the esters and the calculated P-Se bond lengths of the model compounds.
Preparation and Characterization of Some Unsymmetrical Chlorodiorganophosphines RR'PCl
Han, Jung Su,Wolsberger, Werner
, p. 502 - 504 (2007/10/02)
Some unsymmetrical chlorophosphines RR'PCl were prepared by the reaction of RPCl2 (R = CH3, C2H5, i-C3H7, C6H5) with Grignard reagents R'MgCl (R' = c-C5H9, c-C6H11, i-C3H7) and characterized by elemntal analyses and spectroscopic data (IR, 31P and 13C NMR). - Keywords: Chlorodiorganophosphines, NMR spectra
Synthesis and Properties of Mixed Substituted (Chloroacetyl)organylphenylphosphanes
Lindner, Ekkehard,Merkle, Ralf Dieter,Mayer, Hermann August
, p. 645 - 658 (2007/10/02)
The mono-, di- and trichloroacetylorganylphenylphosphanes X1X2CClC(O)PPhR (3av-cz) are obtained by reaction of Me3SiPPhR (2v-z) with the azid chlorides X1X2CClC(O)Cl (1a-c).Increasing content of chlorine results in a shift of the >C=O band and the 31P signal to higher wavelengths and fields, respectively, in the IR and 31P NMR spectra of 3av-cz.Due to the centre of chirality at the phosphorus atom in the 1H NMR spectra one observes diastereotopic protons in the chloroacetyl moiety of 3av-az and of the P-adjacent CH2 protons of 3aw-cw and 3ay-cy.The magnetic inequivalence of both methyl substituents in the isopropyl groups of 3ax-cx is observable also in the 13C and 1H NMR spectra.Because of steric reasons the free rotation about the P-isopropyl axis is hindered up to 355 K.From the coalescence temperature the free activation energy ΔG* is calculated to give 74.7 kJ/mole.The degradation of the thermolabile compounds 3av-cz results in the formation of the chlorophosphanes 5v-z.Individual investigations on 3bv, 3bw and 3by indicate the formation of mono- and dichloroacetyl chloride.The appearance of ClCH2C(O)Cl proceeds via the chloroketene 4b.
