25979-07-1Relevant academic research and scientific papers
Tetra-tert-butylcyclotetraphosphane, 4
Weigand, Willis,Cordes, A. W.,Swepston, Paul N.
, p. 1631 - 1634 (1981)
C16H36P4, monoclinic, P21/c, a=9.391 (1), b=14.029 (2), c=16.854 (2) Angstroem, β=95.80 (1) deg, V=2196 Angstroem3, Z=4, Do (by flotation in ZnCl2 solution)=1.08, Dc=1.07 Mg m-3.The central P4 ring is non-planar with P-P distances of 2.212 (2) Angstroem and P-P-P-P torsion angles of 24.5 deg.The tert-butyl groups are on alternate sides of the ring such that the molecule very nearly possesses 42m symmetry.The final R was 0.037 for the 1981 observed reflections.
Stereochemical Alignment in Triphospha[3]ferrocenophanes
Borucki, Stefan,Kelemen, Zsolt,Maurer, Martin,Bruhn, Clemens,Nyulászi, László,Pietschnig, Rudolf
, p. 10438 - 10450 (2017)
A series of triphospha[3]ferrocenophanes of the type Fe(C5H4-PtBu)2PX with X=H, F, Cl, Br, I, NEt2, tBu has been prepared and characterized by heteronuclear NMR spectroscopy and X-ray crystallography. Despite having three stereogenic centers, the selective formation of a reduced number of diastereomers (either one or two) has been observed for these ferrocenophanes. Theoretical calculations revealed that the inversion of the central stereogenic center inverts the frontier orbital sequence leading to either an iron or a phosphorus centered HOMO depending on the respective diastereomer. CV measurements supported these results. For the all-tert-butyl substituted [3]ferrocenophane Fe(C5H4)2(PtBu)3 a chiral staggered conformation has been found in the solid state which differs substantially from the only other all-organo substituted [3]ferrocenophane, Fe(C5H4)2(PPh)3.
NMR study (1H, 13C, 29Si, 31P and 119Sn) of the (C2H5)(3-n)PIVB(CH3)3 > n compounds (EIVB = C, Si, Sn; n = 0, 1, 2, 3)
Linthoudt, J. P. van,Berghe, E. V. van den,Kelen, G. P. van der
, p. 17 - 22 (1980)
1H, 13C, 29Si, 31P and 119Sn high-resolution NMR spectra of the series (C2H5)(3-n)PIVB(CH3)3 > n (EIVB = C, Si, Sn; n = 0, 1, 2, 3) have been studied at 90 and 300 Mc.The observed trend of chemical shifts and coupling constants are discussed in terms of inductive effects, through-space interactions and rehybridization of the phosphorus atom.Conclusive arguments in favor of d-orbital participation in the P-EIVB bonds were not found.
A new and convenient approach for the synthesis of P-stereogenic intermediates bearing a tert-butyl(methyl)phosphino group
Liu, Yang,Ding, Boqiang,Liu, Delong,Zhang, Zhenfeng,Liu, Yangang,Zhang, Wanbin
, p. 4959 - 4966 (2017)
Chiral organophosphorus compounds possessing a P-stereogenic center have been widely used as agricultural chemicals, pharmaceuticals, organocatalysts, and ligands for transition-metal catalysis. P-Stereogenic intermediates bearing a tert-butyl(methyl)phosphino group are important for the preparation of several commonly used diphosphine ligands. However, previously reported synthetic methods used hazardous starting materials and are difficult to operate. In order to overcome these limitations, a new and convenient synthesis for a number of P-stereogenic intermediates possessing a tert-butyl(methyl)phosphino group has been developed. The reported route relies on an air- and moisture-stable secondary phosphine oxide prepared from a readily available starting material, trichlorophosphane.
Ferrocene-containing sterically hindered phosphonium salts
Ermolaev, Vadim,Gerasimova, Tatiana,Kadyrgulova, Liliya,Shekurov, Ruslan,Dolengovski, Egor,Kononov, Aleksandr,Miluykov, Vasily,Sinyashin, Oleg,Katsyuba, Sergei,Budnikova, Yulia,Khrizanforov, Mikhail
, (2018/10/31)
The synthesis and physical properties of the series of the ferrocenyl-containing sterically hindered phosphonium salts based on di(tert-butyl)ferrocenylphosphine is reported. Analysis of voltamogramms of the obtained compounds revealed some correlations b
Phosphorus chiral important intermediate preparation method
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Paragraph 0028; 0030; 0031; 0032, (2018/09/11)
The invention discloses a phosphorus chiral important intermediate preparation method, which comprises: carrying out a substitution reaction on phosphorus trichloride and tert-butyl magnesium chlorideto obtain tert-butyl phosphine dichloride I; carrying out an esterification reaction on the tert-butyl phosphine dichloride I and ethanol to obtain tert-butyl ethyl phosphite II; carrying out a methylation reaction on the tert-butyl ethyl phosphite II under the action of a methyl Grignard reagent methyl magnesium iodide to generate methyl tert-butyl phosphine oxide III; and obtaining a methyl tert-butyl phosphine hydrogen compound VI protected with borane through a borane reduction one-pot method. According to the present invention, the method has advantages of low-cost and easily-available raw material, short route, simple operation and good atomic economy, and provides the simple and easy-performing route for the preparation of the borane methyl tert-butyl phosphine hydrogen.
Phosphenium-insertion and chloronium-addition reactions involving the cyclo-phosphanes (t-BuP)n (n≤3, 4)
Holthausen, Michael H.,Knackstedt, Dane,Burford, Neil,Weigand, Jan J.
, p. 1155 - 1162 (2013/10/22)
The transfer of a Ph2P+-moiety provided by Ph2PCl and chloronium-addition with PCl5 or PhICl2 to the cyclo-phosphanes (t-BuP)n (n≤3 (4), 4 (5)) were investigated. The reactions strongly depend on the presence of GaCl3 or Me3SiOTf as a halide abstracting reagent. The reaction of 4 with Ph2PCl and GaCl3 quantitatively yields cation [Ph2P(t-BuP)3]+ (6+) as a GaCl4 - salt. Using Me3SiOTf as a halide abstracting reagent leads to the ring expansion of (t-BuP)3 (4) to tetrameric (t-BuP)4 (5) and cation 6+ is only formed as a minor product. Chloronium addition employing the PCl5/GaCl3 or PhICl2/Me3SiOTf systems as Cl+-sources to 4 gives complex reaction mixtures. In contrast, the Cl+-addition to 5 gives cation [Cl(t-BuP)4]+ (8+) quantitatively when the system PCl5/GaCl3 is used. Utilising PhICl2 in the presence of Me3SiOTf gives t-BuPCl2 as the main product.
Alkyl group VA metal compounds
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, (2008/06/13)
Disclosed are methods of preparing monoalkyl Group VA metal dihalide compounds in high yield and high purity by the reaction of a Group VA metal trihalide with an organo lithium reagent or a compound of the formula RnM1X3?n, where R is an alkyl, M1 is a Group IIIA metal, X is a halogen and n is an integer fro 1 to 3. Such monoalkyl Group VA metal dihalide compounds are substantially free of oxygenated impurities, ethereal solvents and metallic impurities. Monoalkyl Group VA metal dihydride compounds can be easily produced in high yield and high purity by reducing such monoalkyl Group VA metal dihalide compounds.
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.
Alkyl group VA metal compounds
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Page 6, (2008/06/13)
A method of preparing Group VA organometal compounds in high yield and high purity by the reaction of a Grignard reagent with a Group VA metal halide in certain ethereal solvents is provided. A method of preparing Group VA organometal hydrides is also provided.
