- Facial conversion of secondary phosphine oxides R1R2P(O)H to chlorophosphines R1R2PCl by acetyl chloride
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A practically useful protocol for the reductive transformation of secondary phosphine oxides R1R2P(O)H to chlorophosphines R1R2PCl using acetyl chloride was disclosed. Various secondary phosphine oxides could be readily reduced to the corresponding chlorophosphines in high yields under mild conditions.
- Zhang, Jian-Qiu,Yang, Shangdong,Han, Li-Biao
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Read Online
- Radical-initiated P,P-metathesis reactions of diphosphanes: Evidence from experimental and computational studies
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By combining the diphosphanes Ar2P-PAr2, where Ar = C6H5, 4-C6H4Me, 4-C6H4OMe, 3,5-C6H3(CF3)2, it has been shown that P,P-metathesis generally occurs rapidly under ambient conditions. DFT calculations have shown that the stability of unsymmetrical diphosphanes Z2P-PZ′2 is a function of the difference between the Z and Z′ substituents in terms of size and electronegativity. Of the mechanisms that were calculated for the P,P-metathesis, the most likely was considered to be one involving Ar2P radicals. The observations that photolysis increases the rate of the P,P-metatheses and TEMPO inhibits it, are consistent with a radical chain process. The P,P-metathesis reactions that involve (o-Tol)2P-P(o-Tol)2 are anomalously slow and, in the absence of photolysis, were only observed to take place in CHCl3 and CH2Cl2. The role of the chlorinated solvent is ascribed to the formation of Ar2PCl which catalyses the P,P-metathesis. The slow kinetics observed with (o-Tol)2P-P(o-Tol)2 is tentatively attributed to the o-CH3 groups quenching the (o-Tol)2P radicals or inhibiting the metathesis reaction sterically.
- Branfoot, Callum,Young, Tom A.,Wass, Duncan F.,Pringle, Paul G.
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Read Online
- Monoacylphosphine oxides with substituents in the phosphonyl moiety as Norrish I photoinitiators: Synthesis, photoinitiattion properties and mechanism
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In order to study the effect of the substituents in the phosphonyl moiety of monoacylphosphine oxide (MAPO) on its stability and initiation performance, (2,4,6-trimethylphenyl)(phenyl)(benzoyl)phosphine oxide (TMBPO), (4-tolyl)(phenyl)(2,4,6-trimethylbenzoyl)phosphine oxide (4-MTPO) and (2,4-xylyl)(phenyl)(2,4,6-trimethylbenzoyl)phosphine oxide (2,4-DMTPO) were designed and prepared. Studies on TMBPO showed that the introduction of methyl groups into the phosphonyl moiety of MAPO significantly enhanced its stability and light absorption abilities. The photopolymerization of trimethylolpropane triacrylate (TMPTA) showed that the initiation efficiency of 4-MTPO and 2,4-DMTPO were higher than that of TPO, regardless of whether it was initiated upon LED at 385 nm or 420 nm. In addition, the migration rates of 4-MTPO and 2,4-DMTPO in cured TMPTA were approximately 1/2 and 1/4 that of TPO, respectively.
- Duan, Haodong,Gao, Jun,Han, Yuxi,Leng, Kangwei,Li, Qianmin,Liu, Dayong,Wang, Zhongwei,Xu, Xiaolei,Yu, Qing
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- Synthetic method of RRPCl
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The invention provides a synthetic method of RRPCl, and belongs to the field of organic matter synthesis. The synthetic method of RRPCl solves the problems of low reaction yield and the like in the existing RRPCl synthesis, and is characterized in that RRP(O)H is dissolved in an organic solvent and then reacts with acetyl chloride to obtain the RRPCl, and the chemicalreaction formula of the RRPCl is shown as a formula (I), wherein R1 and R2 are aryl and alkyl. The synthetic method has the advantages of the high yield and the like.
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Paragraph 0027-0041
(2020/04/06)
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- Novel method for synthesizing chlorodiphenylphosphine by one-step process
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The invention relates to a novel method for synthesizing chlorodiphenylphosphine by a one-step process. The method comprises the following steps: respectively adding phosphorus trichloride, benzene and aluminum trichloride into a three-necked bottle, performing programmed heating to 140-150 DEG C while stirring under the protection of nitrogen, carrying out a heat insulation reaction at the temperature of 140-150 DEG C until no reflux state, and cooling the obtained reaction solution to room temperature; adding an organic solvent to the reaction solution, performing stirring for several hours,dropwise adding a decomplexing agent, stirring the obtained solution for several hours after the drop-by-drop addition of the decomplexing agent is finished, standing the solution to layer the solution, separating out the obtained decomplexing agent layer, carrying out reduced pressure distillation on the obtained organic solvent layer to obtain crude chlorodiphenylphosphine, and distilling the crude chlorodiphenylphosphine under a high vacuum to obtain pure chlorodiphenylphosphine. The method reduces the environmental pollution by recovering the aluminum trichloride, increases the yield of abyproduct, increases the income, and also has the advantages of high yield, low cost and short reaction time.
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Paragraph 0030; 0032-0039
(2019/07/17)
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- Synthesis method of diphenylphosphine chloride
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The invention discloses a synthesis method of diphenylphosphine chloride, belongs to that technical field of chemical synthesis and solves the problem of low yield of the prior diphenylphosphoric chloride product. The synthesis method of diphenylphosphine chloride is characterized by comprising the following steps: under that protection of dry nitrogen, opening and stirring, adding benzene, phosphorus trichloride and catalyst to a reactor, and raising the temperature to 50 DEG C-80 DEG C and performing reflux reaction at 50 DEG C-80 DEG C for 2-3 h; after the reaction in step S01 is completed, raising the temperature to 85-200 DEG C and performing reflux reaction at 85-200 DEG C; at that end of step S02, after the reactor is cooled down, adding benzene into the reactor, adding a decomplexing agent, stirring until the decomplexing agent is dissolved and distilling to remove benzol, and then performing vacuum distillation to obtain the front fraction and the rear fraction. The inventionhas the advantages of high product yield.
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Paragraph 0030-0047
(2019/10/01)
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- Synthesis and characterization of new PNNP-type chiral ligands
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Polydentate ligands having both soft and hard centers are very effective ligands for the preparation of transition metal complexes. PNNP-type tetradentate diaminodiphosphine ligands are most preferred ligand types cause of their good efficiency for the asymmetric reactions. In this study, three different iminophosphine derivative PNNP-type chiral ligands were synthesized using (R)-(+)-1,1′-Binaphthyl-2,2′-diamine (R-BINAM) and d?phenylphosph?no benzaldehyde derivatives.
- Tezcan, Burcu,Güzel, Bilgehan
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p. 315 - 316
(2018/12/11)
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- Method for preparing alkyl phosphine hahalide and reactor for method
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The invention relates to a method for preparing compounds as shown in a formula (I) and a formula (II) which are shown in the description and a reactor specially used for implementing the method. In the formula (I) and the formula (II), X represents halogen, and R represents an alkyl group. The method comprises the step of enabling yellow phosphorus to react with the compound as shown in a formula(III) in a reactor under a condition that no catalyst exists. The method is characterized in that a material on the surface, which is in contact with reaction space, in the reactor is nickel-based alloy used as anti-corrosion alloy, or the reactor is totally formed by the nickel-based alloy used as the anti-corrosion alloy along the whole reaction wall thickness direction. According to the methoddisclosed by the invention, the nickel-based alloy used as the anti-corrosion alloy is adopted as the material of the reactor and accessories of the reactor, an improved anti-corrosion effect betterthan that of an existing reactor and accessories thereof can be realized, and the cost is acceptable, so that the method can be realized in an industrial scale.
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Paragraph 0117; 0118; 0121; 0122; 0125; 0126
(2019/01/06)
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- Method for preparing diarylphosphoryl chloride compound
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The invention discloses a method for preparing a diarylphosphochlorine compound and belongs to the field of organic synthesis. The method is as follows: the diarylphosphochlorine compound is preparedby reaction of triarylphosphine as a starting material with phosphorus trichloride in the presence of zinc trifluoromethanesulfonate as a catalyst and distillation. Compared with the prior art, the method has the advantages of high reaction yield and simple post-treatment, is particularly suitable for preparation of the diarylphosphochlorine compound with a substituent, and is more suitable for industrial production. The obtained diarylphosphochlorine compound can be used as a ligand for synthesizing metal catalysts, and is applied to the fields such as organic photoelectric materials and medicines.
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Paragraph 0014-0015
(2018/06/15)
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- A twin-sulfur [...]/aryl heterocyclic compound phosphoric acid as the auxiliary ligand iridium complex of (by machine translation)
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The invention relates to a nitrogen heterocyclic main ligand, in order to double-sulfur [...]/aryl heterocyclic phosphate compound as auxiliary ligand new iridium complex. Iridium complex molecular nitrogen heterocyclic and sulfur group contribute to improving the material of the electron mobility and control light-emitting color, so as to balance the cavity with electronic injection and transmission, widen the carrier composite area, promote the device efficiency, reduce efficiency roll-off. The invention the iridium complex synthetic simple, stable chemical property, easy to sublimation purification, device performance, in order to obtain high efficiency of the organic electroluminescent device and its application in the field of lighting and display provides the convenience. (by machine translation)
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Paragraph 0033; 0034; 0038
(2018/09/21)
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- Asymmetric Synthesis of Chiral Primary Amines by Ruthenium-Catalyzed Direct Reductive Amination of Alkyl Aryl Ketones with Ammonium Salts and Molecular H2
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A ruthenium/C3-TunePhos catalytic system has been identified for highly efficient direct reductive amination of simple ketones. The strategy makes use of ammonium acetate as the amine source and H2 as the reductant and is a user-friendly and operatively simple access to industrially relevant primary amines. Excellent enantiocontrol (>90% ee for most cases) was achieved with a wide range of alkyl aryl ketones. The practicability of this methodology has been highlighted by scalable synthesis of key intermediates of three drug molecules. Moreover, an improved synthetic route to the optimal diphosphine ligand C3-TunePhos is also presented.
- Tan, Xuefeng,Gao, Shuang,Zeng, Weijun,Xin, Shan,Yin, Qin,Zhang, Xumu
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supporting information
p. 2024 - 2027
(2018/02/19)
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- Semiconducting Material Comprising a Phosphine Oxide Matrix and Metal Salt
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The present invention is directed to a semiconducting material comprising: i) a compound according to formula (I) wherein R1, R2 and R3 are independently selected from C1-C30-alkyl, C3-C30 cycloalkyl, C2-C30-heteroalkyl, C6-C30-aryl, C2-C30-heteroaryl, C1-C30-alkoxy, C3-C30-cycloalkyloxy, C6-C30 aryloxy, and from structural unit having general formula E-A-, wherein—A is a C6-C30 phenylene spacer unit, and—E is an electron transporting unit that is selected from C10-C60 aryl and C6-C60 heteroaryl comprising up to 6 heteroatoms independently selected from O, S, P, Si and B and that comprises a conjugated system of at least 10 delocalized electrons, and—at least one group selected from R1, R2 and R3 has the general formula E-A-; and ii) at least one complex of a monovalent metal having formula (II) wherein—M+ is a positive metal ion bearing a single elementary charge, and each of A1, A2, A3 and A4 is independently selected from H, substituted or unsubstituted C6-C20 aryl and substituted or unsubstituted C2-C20 heteroaryl, wherein a heteroaryl ring of at least 5 ring-forming atoms of the substituted or unsubstituted C2-C20 heteroaryl comprises at least one hetero atom selected from O, S and N.
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- Comparison of the reactivity of 2-amino-3-chloro- and 2,3- dichloroquinoxalines towards Ph2PH and Ph2PLi and of the properties of diphenylphosphanyl-quinoxaline P,N and P,P ligands
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The synthesis of quinoxaline P,N ligands by monoamination of 2,3-dichloroquinoxaline (1) to 2-amino-3-chloroquinoxalines 2a,b and the subsequent substitution of chlorine by a diphenylphosphanyl group was studied. Whereas the reaction of 2a,b with Ph2PH in the presence (or absence) of catalytic amounts of palladium acetate furnished only minor amounts of the expected ligands in favor of tetraphenyldiphosphane and dechlorinated quinoxalines, the coupling with Ph2PLi in ether provided the novel NH-functional P,N hybrid ligands 3a,b with a quinoxaline scaffold in moderate to good yields. 3a is slightly and 3b somewhat more sensitive to air oxidation, leading to the P-oxides 4a,b. The more reactive 1 forms with Ph2PH only a small amount of 2-chloro-3-diphenylphosphanylquinoxaline 5 and traces of the quinoxaline-bis(phosphane) 6. The main products are 2,2′- bis(quinoxaline) and Ph2PCl, which converts residual Ph2PH into tetraphenyldiphosphane. The coupling with Ph2PLi in diethyl ether, however, gave in a fast reaction high yields of 6, exceeding those of 3a,b, with interfering NH functions. Semi-empirical quantum chemical calculations (PM6) illuminate the background of the air sensitivity of 3a,b, whereas the recently reported 6 is air stable. Preliminary studies for use of the ligands in catalysis with the air-stable 6, showed moderate to good yields in the Pd-catalyzed C-N cross coupling of 2-bromopyridine with mesityl amine. Complex formation was confirmed by isolation of the Pd complex 7. The structure elucidation of the new compounds is based on conclusive NMR data and crystal structure analyses for 2b, 3a, 4a and 4b.
- Adam, Mohamed Shaker S.,Mohamad, Ahmad Desoky,Jones, Peter G.,Kindermann, Markus K.,Heinicke, Joachim W.
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p. 101 - 111
(2013/03/28)
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- Catalyst for Synthesizing 1-Hexene from Ethylene Trimerization and Application Thereof
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A catalyst for synthesizing 1-hexene from ethylene trimerization and its application are provided. Said catalyst consists of (a) the compound containing P and N, (b) electron donor, (c) Cr compound, (d) carrier and (e) accelerator. The molar ratio of (a), (b), (c), (d) and (e) is 0.5-100:0.5-100:1:0.5-10:50-5000. The catalyst is prepared by mixing the components of (a)-(e) in an ethylene trimerization apparatus in situ and ethylene is introduced into the apparatus continuously. The prepared catalyst can be used to synthesize 1-hexene from ethylene trimerization in the inert solvents. The trimerization is performed at 30-150° C. and 0.5-10.0 MPa for 0.1-4 hours. The catalyst has high catalytic activity and high 1-hexene selectivity. During the process of ethylene trimerization, by-product polyethylene does not stick to the apparatus.
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Page/Page column 2
(2012/12/14)
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- Imidazoliophosphines are true N-heterocyclic carbene (NHC)-phosphenium adducts
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Whereas the external nucleophilic reactivity of α-amidiniophosphines has been previously illustrated by their complexation to transition-metal centers, their internal electrophilic reactivity is herein investigated by using BIMIONAP (BIMIONAP=N-methylated BIMINAP cation, BIMINAP=formal contraction of the acronyms BIMIP=2,2′-bis(diphenylphosphino)-1,1′-bibenzimidazole and BINAP=2,2′-bis(diphenylphosphino)-1,1′-binaphthyl). Reaction of tetraethylammonium chloride with free BIMIONAP is found to induce heterolytic cleavage of the N2C-P bond to give chlorodiphenylphosphine and a transient phosphine-N-heterocyclic carbene (NHC) species that is trapped in situ by protonation to the corresponding phosphine-benzimidazolium cation. When the chloride anion reacts with the cationic [Pd(η2-BIMIONAP)Cl 2] complex, the same cleavage occurs and the phosphine-NHC moiety is trapped in the corresponding [PdCl2(η2-phosphine-NHC)] complex. When the chloride anion reacts with the dicationic [Pd(π-allyl)(η2-BIMIONAP)]+ complex, allyldiphenylphosphine is produced, and the [PdCl(η2-phosphine- NHC)(PPh2CH2CH=CH2)]+ complex is obtained. Reaction of free BIMIONAP with the harder n-butyllithium nucleophile also induces heterolytic cleavage of the N2C-P bond, from which the phosphine-NHC moiety is trapped by hydrolysis of the benzimidazole ring or by P,C-sulfurization. Cleavage of a C-P bond with the weak Cl- nucleophile to release the reactive NHC moiety (according to the unusual scheme C-P+Cl-→C:+Cl-P) is a definite experimental indication of the dative nature of the N2C-P bond of amidiniophosphines, which are, therefore, better described as NHC→phosphenium adducts. This interpretation is supported by the calculation, at the DFT level, of a heterolytic dissociation mode of the N2C-P bond lower in energy than the homolytic one. A mesomeric description of the NHC→phosphenium entity is also proposed on the basis of electron localization function (ELF) and atoms in molecules (AIM) analyses. Finally ELF and AIM-based Fukui indices, molecular orbitals, and MESP analyses show that the initial attack of Cl- takes place at the carbenic atom of BIMIONAP. Addition of anionic nucleophiles (Cl-, nBu-) to free BIMIONAP and BIMIONAP-containing palladium complexes results in selective cleavage of the N2C-P bond, from which the released N-heterocyclic carbene (NHC) fragment can be trapped by protonation, hydrolysis, sulfurization, or coordination to PdII centers (see scheme).
- Abdellah, Ibrahim,Lepetit, Christine,Canac, Yves,Duhayon, Carine,Chauvin, Remi
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experimental part
p. 13095 - 13108
(2011/02/24)
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- METHOD FOR PREPARING HALOGENATED ORGANOPHOSPHINES
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The present application relates to a process for preparing a halogenated organophosphine, comprising reacting a primary or secondary organophosphine with a halogenating agent selected from (A) a compound of formula (I) : (HaI)3C-C(O)-X (I) wherein X is selected from alkyl, aryl, aralkyl, alkaryl, cycloalkyl, NR1R2, C(HaI)3, OR3, -0-C(O)-R3', or -Y-Z-Y-C(O)- C(HaI)3; R1 and R2 are each independently selected from hydrogen, alkyl, aryl, aralkyl, alkaryl, or cycloalkyl; R3 is selected from H, alkyl, aryl, aralkyl, alkaryl, cycloalkyl, or triorganosilyl; R3' is selected from C(HaI)3, alkyl, aryl, aralkyl, alkaryl, cycloalkyl; Y is independently selected from 0 or NH; Z is independently selected from alkylene, arylene, aralkylene, alkarylene, or cycloakylene; and Hal is selected from Cl or Br; or (B) a derivative of a polyol, polyamine or polyaminoalcohol comprising two or more hydroxyl and/or amino groups, in which a hydrogen atom in each of the hydroxyl and/or amino groups is replaced with a group -C(O)-C(HaI)3, wherein Hal is selected from Cl or Br.
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Page/Page column 18-19
(2009/12/28)
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- Unprecedented rearrangement during the formation of P-P homoatomic N-phosphino formamidine complexes
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A variety of homoatomic P-P donor-acceptor homoleptic (R = R′) and heteroleptic (R ≠ R′) N-phosphino formamidine complexes [iPr2N-C(H){double bond, long}N-PR2-PR′2]Cl were synthesized from the addition of N-phosphino forma
- Le, Thanh D.,Arquier, Damien,Miqueu, Karinne,Sotiropoulos, Jean-Marc,Coppel, Yannick,Bastin, Stéphanie,Igau, Alain
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body text
p. 229 - 236
(2009/04/13)
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- Ethylene tetramerization: A new route to produce 1-octene in exceptionally high selectivities
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Linear α-olefins, such as 1-hexene and 1-octene, are important comonomers in the production of linear low-density polyethylene (LLDPE). The conventional method of producing 1-hexene and 1-octene is by oligomerization of ethylene, which yields a wide spectrum of linear α-olefins (LAOs). While there exists several processes for producing 1-hexene via ethylene trimerization, a similar route for the selective production of 1-octene has so far been elusive. We now, for the first time, report an unprecedented ethylene tetramerization reaction that produces 1-octene in selectivities exceeding 70%, using an aluminoxane-activated chromium/((R2)2P)2NR1 catalyst system. Copyright
- Bollmann, Annette,Blann, Kevin,Dixon, John T.,Hess, Fiona M.,Killian, Esna,Maumela, Hulisani,McGuinness, David S.,Morgan, David H.,Neveling, Arno,Otto, Stefanus,Overett, Matthew,Slawin, Alexandra M. Z.,Wasserscheid, Peter,Kuhlmann, Sven
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p. 14712 - 14713
(2007/10/03)
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- Investigation of the reaction between diphenylphosphine and carbon tetrachloride
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The mechanism of diphenyltrichloromethylphosphine (4) formation in the title reaction has been studied. It has been established that the diphenyltrichloromethylphosphine is formed in the multistep reaction sequence (Scheme 1), which involves the intermediacy of chlorodiphenylphosphine (2) and tetraphenyldiphosphine (3). This process is analogous to the formation of dialkyltrichloromethylphosphines in the dialkylphosphine / CCl4 reaction.
- Majewski, Piort
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p. 399 - 406
(2007/10/03)
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- Synthesis of stable N′,N′,N″,N″-tetramethylguanidine-Substituted σ4(P)- and σ3(P)-organophosphorus compounds with N-protonated P-N bonds the first σ3-phosphorus-substituted ammonium salts
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The dependence of the protolytic decomposition rate of phosphorus amides on the substituents at phosphorus is decribed. On treatment with HCl, the N′,N′,N″,N″-tetramethylguanidine(= TMG)-substituted σ4(P) compounds 5 and 9 formed salts that were protonated at the imino nitrogen atoms and were completely stable in the solid state, and surprisingly stable in solution. Even with a large excess of HCl, only the imino nitrogen atom underwent protonation, with formation of HCl2- as a counter anion, without cleavage of the P-N bond. The basicity of the imino nitrogen atom also protected σ3(P) species from electrophilic attack, and the ionic compounds 12, 14, and 20c were formed, providing examples of the first stable σ3(P) amides with one or two protonated P-N bonds. Such unusual stability is associated with steric protection by the Ph3C (= trityl) group and charge delocalization over the TMG-moiety. In contrast, MeP(TMG)2 was unstable towards HCl, whereas treatment with HSbF6 led to the phosphonium salt 24, where protonation had occurred at phosphorus. The same result was obtained when triphenylmethylphosphonous dichloride 1 was allowed to react with 3 equivalents of HTMG, forming the stable phosphonium salt 19, soluble in water, which was converted to the bicationic species 20c upon treatment with HCl. - The basicity of the tritylated phosphorus compounds was found to increase in the order 5 3N · 3 HF caused rapid conversion of compound 6 to 25, the nucleophilic attack of fluoride ion at phosphorus could not be prevented by the stabilizing effects mentioned. - All compounds were investigated by 1H- and 31P-NMR spectroscopy. The crystal structures of compounds 5, Ph3CP(=O)-(H)TMG,and 6, [5 · 2 HCl], were determined; 6 is protonated at the imino nitrogen, leading to a longer P-N bond [5: 161.6(2), 6: 168.7(2) pm], and the counterion is HCl2-. In the structure of 20c, [Ph3CP(TMG)2] · 3 HCl, the cation is protonated at both imino N atoms and the counterions are Cl- and HCl2- (one of each).
- Plack, Volker,Mu?nchenberg, Jochen,Tho?nnessen, Holger,Jones, Peter G.,Schmutzler, Reinhard
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p. 865 - 875
(2007/10/03)
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- Flash vacuum pyrolysis of dichlorophosphines over magnesium: Generation and reactivity of simple phosphinidenes
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Flash vacuum pyrolysis of dichlorophosphines over magnesium at 500-600 °C gives the products expected from intramolecular CH insertion of the corresponding phosphinidenes.
- Aitken, R. Alan,Masamba, Wayiza,Wilson, Neil J.
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p. 8417 - 8420
(2007/10/03)
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- Carbohydrate Phosphinites as Practical Ligands in Asymmetric Catalysis: Electronic Effects and Dependence of Backbone Chirality in Rh-Catalyzed Asymmetric Hydrogenations. Synthesis of R- or S-Amino Acids Using Natural Sugars as Ligand Precursors
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Vicinal diarylphosphinites derived from carbohydrates are excellent ligands for the Rh(I)-catalyzed enantioselective asymmetric hydrogenation of dehydroamino acid derivatives, producing the highest enantioselectivity of any ligands directly prepared from natural products. The enantioselectivity can be enhanced by the appropriate choice of substituents on the aromatic rings of the phosphinites. For example, the use of phosphinites with electron-donating bis(3,5-dimethylphenyl) groups on phosphorus provides ee's up to 99% for a wide range of amino acids including some with easily removable N-protecting groups. Electron-withdrawing aryl substituents, on the other hand, decrease the enantioselectivity. Sense of chiral induction in the amino acid product depends on the relative juxtaposition of the vicinal diphosphinites on a given sugar backbone. When readily available D-glucopyranosides are used as the starting sugars, 2,3-phosphinites give the S-amino acids and 3,4-phosphinites give the R-amino acids. In the case of aromatic and heteroaromatic amino acids, enantioselectivities > 95% are consistently obtained. Practical considerations such as the ease of ligand synthesis, rates of reactions, catalyst turnover, and scope and limitations in terms of substrates are discussed. A possible explanation for the enhancement of enantioselectivity by electron-rich phosphinites is offered.
- RajanBabu,Ayers, Timothy A.,Halliday, Gary A.,You, Kimberly K.,Calabrese, Joseph C.
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p. 6012 - 6025
(2007/10/03)
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- A NEW, UNEXPECTED REACTION OF PHOSPHONOCHLORIDOTHIONATES WITH ALKYL ARYL ETHERS AND ALKYL CHLORIDES UNDER THE FRIEDEL-CRAFTS REACTION CONDITIONS
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Phosphonochloridothionates have been found to react in the presence of Lewis acids with alkyl aryl ethers to give S-alkyl O-aryl phosphonothiolates and with alkyl halides to form products of the S-alkylation. Key words: Alkyl arel ethers; phosphonochloridothionates; alkylation; S-alkyl O-aryl phosphonothiolates; S-alkyl alkyl(aryl) dichlorophosphonium salts; conductivity.
- Omelanczuk, Jan
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- INVESTIGATION OF THE REACTION BETWEEN BENZENE, PHOSPHORUS TRICHLORIDE, AND ALUMINUM CHLORIDE BY MEANS OF 31P NMR SPECTROSCOPY
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Reaction between C6H6, PCl3, and AlCl3 at 60-160 deg C and reactant ratios of (1-3): 1:1 was studied by means 31P NMR spectroscopy.Reaction starts at 60-70 deg C with the formation of the salt +AlCl4-.The subsequent transformation of this salt at 130-140 deg C includes two alternative processes: a) the direct replacement of P-chloro by aryl; b) intramolecular interaction and disproportionation with the subsequent formation of phosphinophosphonium salts +Al2Cl7- and +AlCl7-.Both courses lead to the formation of the salt +AlCl4-.The structures of the intermediates were proved by model reactions of phenylphosphonous dichloride and diphenylphosphinous chloride with aluminum chloride.By the reactions of the salt +AlCl4- with halobenzenes we proved that the process goes predominantly by course (b).The highest yield of diarylphosphinous chlorides was obtained with optimum proportions of the reactants of 2:1:1.
- Tarasova, R. I.,Zykova, T. V.,Shagvaleev, F. Sh.,Sitdikova, T. Sh.,Moskva, V. V.
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p. 2346 - 2349
(2007/10/02)
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- REACTION OF SECONDARY PHOSPHINES WITH CARBON TETRACHLORIDE. SYNTHESIS OF ALKYLACYLCHLOROPHOSPHINES
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We present a method for the synthesis of hitherto unknown chlorides of alyklacylphosphinic acids by reaction of alkylacylphosphines with carbon tetrachloride in the presence of triethylamine.We have discovered a reaction of chlorides of alkylacylphosphinic acids in which intermolecular migration of an acyl group takes place.
- Veits, Yu. A.,Neganova, E. G.,Filippov, M. V.,Borisenko, A. A.,Foss, V. L.
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p. 114 - 118
(2007/10/02)
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- SYNTHESIS AND CHEMISTRY OF DIALKYL- AND DIARYLTRICHLOROMETHYLPHOSPHINES
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Dialkyltrichloromethylphosphines; diphenyltrichloro-methylphosphine; P-chloro-dialkyl-dichloromethylenephosphoranes; P-chloro-diphenyl-dichloromethylenephophorane; phosphonium salt; chlorination; dehydration; condensation.
- Majewski, Piotr
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p. 185 - 194
(2007/10/02)
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- Process for the preparation of aromatic phosphorus-chlorine compounds
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Aromatic phosphorus-chlorine compounds, especially diphenylphosphinyl chloride (C6 H5)2 P(O)Cl, phenylphosphonyl dichloride C6 H5 P(O)Cl2, dichlorophenylphosphine C6 H5 PCl2 and chlorodiphenylphosphine (C6 H5)2 PCl, and the corresponding sulfur analogs, are obtained by reaction of aromatic phosphorus compounds, which contain oxygen or sulfur, of the formula I STR1 in which X=O or S, and m=1, 2 or 3, with phosphorus-chlorine compounds of the formula II in which n=1, 2 or 3, at temperatures between about 330° and 700° C. Preferred starting materials are triphenylphosphine oxide (C6 H5)3 PO and phosphorus trichloride PCl3. The reaction products are mainly intermediates in a variety of special areas, such as the pharmaceuticals, plant-protection, dye and polymer sectors.
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- Process for preparing chlorophenylphosphanes
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Chlorophenylphosphanes of the formula in which n=1 or 2, are prepared by reacting triphenylphosphane, (C6 H5)3 P, with phosphorus trichloride, PCl3, at temperatures between about 320° and 700° C.; in the temperature range between about 320° and 500° C. the reaction is preferably carried out under elevated pressure, in particular under autogenous pressure, while in the temperature range between about 500° and 700° C. atmospheric pressure is preferably used. The composition of the final product can be controlled by the choice of the molar ratio of the starting materials. The final products dichlorophenylphosphane and chlorodiphenylphosphane are mainly intermediates in various fields, such as, for example, the crop protection and the polymer sectors.
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- THE FORMATION OF P(III) PRODUCTS FROM PHOSPHINAMIDES WITH SILICON HYDRIDES
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Two N,N-diethyl derivatives of phosphinamides in the 3-phospholene series were used as models to develop techniques for reduction to P(III) derivatives.The products from the reduction with HSiCl3 in the presence of pyridine depended on the molar ratio of the participants.A 1:1:1 amide-HSiCl3-pyridine mixture after 2 h in refluxing benzene provided the phosphinous chlorides in preparatively useful (55-65percent) yield.A 1:1.5:1.5 mixture led to coupling at phosphorus to give the diphosphine, also in good yield (60-65percent).The diphosphines also resulted from refluxing a 1:1 mixture at 100o gave only the product of deoxygenation (65percent).A 1-benzylaminophosphetane oxide was also reduced succesfully.The conditions with HSiCl3 and C6H5SiH3 were applied to a noncyclic phosphinamide (C6H5)2PO(NEt2); reaction rates were considerably slower than for the cyclic amides, but similar P(III) products were formed. 13C and 31P NMR spectra are reported for all new compounds.
- Quin, Louis D.,Szewczyk, Jerzy
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p. 161 - 170
(2007/10/02)
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- Preparation, Structure, and Thermal Behaviour of (2-Chloroacyl)diphenylphosphanes - a New Pathway to Chloroketenes
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The chlorinated acylphosphanes RC(O)-PPh2 (2a - f) are obtained by the reaction of the acyl chlorides RC(O)Cl (1a - f) with (CH3)3SiPPh2 in ether at -80 deg C.HCCl2C(O)-PPh2 (2c) crystallizes monoclinicly in the space group P21/c with Z = 8.As a result of steric caused electronic effects with increasing degree of chlorination in the series 2b -> 2c -> 2d a stepwise high field shift of the signals in the 31P-NMR spectra is observed. 2b - d, f are thermally labile and decompose with formation of ClPPh2 (3) and ketene at 80 deg C.The chloroketenes HCClCO (4) and CH3CClCO (5) are detected for the first time directly by means of their 13C NMR spectra.Between 0 and 40 deg C 2d also yields Cl3PPh2 (6).With cyclohexene or aniline 4 reacts to give the trapping products 8 and 9, respectively.
- Lindner, Ekkehard,Steinwand, Michael,Hoehne, Sigurd
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p. 2181 - 2191
(2007/10/02)
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- THE REACTION OF DIPHENYLPHOSPHINE OXIDE WITH DIPHENYLPHOSPHINOUS CHLORIDE IN THE ABSENCE OF BASE
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Diphenylphosphinous chloride (1) and diphenylphosphine oxide (2) (2 mol equivalent) react to form diphenylphosphinic acid (4), together with tetraphenyldiphosphine (5) (at 80 deg C), or its hydrochloride (6) (at 20 deg C), as the only products.
- Hunter, D.,Michie, J. K.,Miller, J. A.,Stewart, W.
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p. 267 - 270
(2007/10/02)
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- Condensation reactions giving rise to P-P bonded compounds
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The room-temperature condensation of CH3P(OCH3)2 with an equimolar amount of (C6H5)2PCl leads to the new compound (C6H5)2P-P(O)(CH3)OCH3, whereas the related reaction between CH3PCl2 and (C6H5)2POCH3 leads first to exchange of the chloro and methoxyl groups followed by slow self-condensation of the resulting CH3P(OCH3)Cl molecules. When CH3P(OCH3)2 is combined with an excess of (C6H5)2PCl, the product is found to react further with this excess reagent to give (C6H5)2P-P(C6H5) 2. Furthermore, the room-temperature reaction of CH3P(OCH3)2 with C6H5PCl2 leads to condensation products apparently based on the combination of the C6H5(CH3O)P- end group with CH3P(O)6H5P(O)3(CH3O)P(O)- group. The new compound (C6H5)2P-P(O)(OCH2) 2C(CH3)2 was obtained by reaction of (C6H5)2POCH3 with (CH3)2C(CH2O)2PCl, whereas, also at room temperature, only exchange of chloro for methoxyl group was observed in the reaction between o-C6H4O2PCl and (C6H5)2POCH3. At 140°, the reagents underwent exchange and condensation to give what appeared to be a P-O-P bridged structure, [C6H4O2P]2O.
- Abraham, Kuzhikalail M.,Van Wazer, John R.
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p. 1099 - 1103
(2007/10/05)
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