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The local structure of triphenyl phosphite studied using spallation neutron and high-energy X-ray diffraction
Mei, Qiang,Ghalsasi, Prasanna,Benmore, Chris J.,Yarger, Jeffery L.
, p. 20076 - 20082 (2004)
Spallation neutron and high-energy X-ray diffraction experiments have been performed to investigate the local structural changes in triphenyl phosphite (TPP) in the crystalline, glacial, glassy, and supercooled liquid phases. The hydrogen/deuterium first-order difference method shows a large increase in intensity due to additional hydrogen correlations in the crystalline spectra compared to the glass and supercooled liquid at a??3.0 and 3.4 Aì?. These features are shown to be largely due to inter-phenyl ring H-C/H interactions, which are probably associated in part with the formation of weak intermolecular hydrogen bonds. The high-energy X-ray diffraction data show a decrease in correlations at 3.12 Aì? which is attributed to changes in C-O/P intramolecular interactions between the glacial and crystalline forms. The structural evolution of the glacial state was also measured over time using total neutron diffraction. The largest structural differences between the early glacial and crystalline states are observed at 3.0 and 4.5 Aì?. Moreover, as the transformation progresses, the glacial spectra cannot be adequately described as a simple mixture of supercooled liquid and crystalline components. These results suggest that changes in molecular conformation and nearest-neighbor interactions are responsible for the existence of the glacial state.
Ruthenium-catalyzed regio- And site-selective: Ortho C-H borylation of phenol derivatives
Homma, Yuki,Fukuda, Kazuishi,Iwasawa, Nobuharu,Takaya, Jun
, p. 10710 - 10713 (2020)
Efficient synthesis of o-borylphenols is achieved through the Ru-catalyzed regio- and site-selective sp2 C-H borylation of aryl diphenylphosphinites followed by removal of the phosphorus directing group. A successful application to aryl phosphites enables practical one-pot borylation of phenols, demonstrating high synthetic utility of this protocol.
Avar,Neumann
, p. 215,222, 223 (1977)
Selective deoxygenation of aryl selenoxides by triaryl phosphites. Evidence for a concerted transformation
Stratakis, Manolis,Rabalakos, Constantinos,Sofikiti, Nikoletta
, p. 349 - 351 (2003)
Triaryl phosphites selectively reduce aryl selenoxides to selenides. The Hammett plot of the reactions of para-phenyl substituted triaryl phosphites with diphenyl selenoxide gave ρ=+2.3, whereas with bis(p-methoxyphenyl) selenoxide, ρ=-2.1. The results are consistent with a concerted mechanism for the oxygen transfer from Se to P.
REACTION OF ELEMENTAL PHOSPHORUS WITH PHENOLS
Ivanov, B. E.,Badeeva, E. K.,Krokhina, S. S.
, p. 2371 - 2373 (1988)
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Gottlieb
, p. 748,750 (1932)
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Substituent effects on the 31P NMR chemical shifts of arylphosphorothionates
Hernández, Javier,Goycoolea, Francisco M.,Zepeda-Rivera, Denisse,Juárez-Onofre, Josué,Martínez, Karla,Lizardi, Jaime,Salas-Reyes, Magali,Gordillo, Bárbara,Velázquez-Contreras, Carlos,García-Barradas, Oscar,Cruz-Sánchez, Samuel,Domínguez, Zaira
, p. 2520 - 2528 (2006)
Six tris(aryloxy)phosphorothionates substituted in the para position of the aromatic rings were synthesized and studied by 31P NMR, X-ray diffraction techniques and ab initio calculations at a RHF/6-31G** level of theory, in order to find the main structural factors associated with the δ31P in these compounds. As the electron-withdrawing (EW) ability of the substituents was increased, an 'abnormal' shielding effect on δ31P of the arylphosphorothionates was observed. The analyses of the geometrical properties obtained through both experimental and theoretical methods showed that a propeller-type conformation is preferred for the arylphosphorothionates, except in the case of the tris(O-4-methylphenyl) phosphorothionate, since one of the aromatic rings is not rotated in the same direction as the other two in the solid state. The main features associated with the δ31P NMR of compounds 1-6 were a decrease of the averaged O-P-O angle and mainly the shortening of the PS bond length, which is consistent with an increase of the thiophosphoryl bond order as δ31P values go upfield. On the other hand, comparison of the experimental and calculated bond lengths and bond angles involving α bonded atoms to phosphorus of the six compounds suggested that stereoelectronic interactions of the type nπO-σ*PS, nπO- σ*P-OAr and nπS-σ* P-OAr could be present in the arylphosphorothionates 1-6.
A novel mild deprotection method for phosphine-boranes
Schroeder, Marc,Nozaki, Kyoko,Hiyama, Tamejiro
, p. 1931 - 1932 (2004)
Treatment of phosphine-boranes with molecular sieves 4A in a mixture of an ethereal solvent and an alcohol provided deprotected free phosphines in quantitative yields. The phosphines can be obtained by a simple filtration/crystallization procedure in most cases. It should be noted that the current method is successfully applied to the deprotection of a phosphite-borane for the first time.
Method for preparing phosphate ester derivatives from white phosphorus
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Paragraph 0035-0052, (2021/06/23)
A method for preparing phosphate ester derivatives from white phosphorus relates to the field of chemical engineering, and comprises the following steps: adding alkali, a catalyst, a white phosphorus solution, ROH or RSH (R represents alkyl or aromatic group) into a reaction container in an inert atmosphere, and heating and stirring the mixture in a mixed solvent of toluene and DMSO (dimethyl sulfoxide) to react for a certain time, so as to obtain three-coordinated phosphate ester derivatives; and 2) continuing to add H2O2, air or sulfur powder until the oxidation is completed, thereby obtaining the tetra-coordinated phosphate ester derivative. According to the method, chlorine, phosphorus trichloride and halogen are not needed, phosphite ester is directly prepared from elementary white phosphorus in an efficient, green and environment-friendly manner, and phosphate and thiophosphate can be directly prepared after oxidation. High pollution and high corrosivity of a traditional method are avoided in the whole process; meanwhile, white phosphorus is completely converted in the whole process, white phosphorus residues are avoided, and the post-reaction treatment process is safe.
Flash production of organophosphorus compounds in flow
Nagaki, Aiichiro,Tamaki, Takashi
supporting information, (2021/09/09)
Flow synthesis techniques have received a significant amount of attention due to their high productivity. However, when reaction condition is heterogeneous, it is usually difficult to adapt it to flow synthesis. Herein, by selecting appropriate reagents, the synthesis of phosphate esters, which is commonly heterogeneous, was made homogeneous, enabling synthesis in flow systems. In addition, reaction rate was accelerated compared to the batch system. It was demonstrated that not only can the high productivity of flow synthesis be achieved in flow, but also high productivity can be achieved by accelerating the reaction. Finally, we demonstrated the synthesis of the Akiyama-Terada catalyst, a chiral organocatalysts, in a short period.