- Extraction Properties of Diphenylposphorylureas with Aliphatic ω-Nitrogen-Containing Substituents
-
Abstract: Extraction of lanthanides and actinides from nitric acid solutions with N-(diphenylphosphoryl)-N'-n-propylureas containing imidazolyl, diethylamino, pyrid-2-yl, 2-oxopyrrolidino fragments in the ω position of the alkyl substituent has been studied. It has been shown that Ho(III) and Yb(III) related to the yttrium subgroup of lanthanides are extracted much better than La(III) and Nd(III) related to the cerium subgroup. N-(Diphenylphosphoryl)urea containing ω-(2-oxopyrrolidino)propyl fragment at the terminal nitrogen atom shows the best extraction properties. This dependence has been theoretically explained by modeling complexation because the coordination of f-block element ion with amide oxygen atom is more preferable
- Baulina, T. V.,Borisova, N. E.,Brel’, V. K.,Goryunov, E. I.,Goryunova, I. B.,Lizunov, A. V.,Safiulina, A. M.
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p. 731 - 739
(2021/06/01)
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- Enantiodivergent Kinetic Resolution of 1,1′-Biaryl-2,2′-Diols and Amino Alcohols by Dipeptide-Phosphonium Salt Catalysis Inspired by the Atherton–Todd Reaction
-
A highly enantiodivergent organocatalytic method is disclosed for the synthesis of atropisomeric biaryls via kinetic resolution inspired by a dipeptide-phosphonium salt-catalyzed Atherton–Todd (A-T) reaction. This flexible approach led to both R- and S-enantiomers by fine-tuning of bifunctional phosphonium with excellent selectivity factors (s) of up to 1057 and 525, respectively. The potential of newly synthesized O-phosphorylated biaryl diols was illustrated by the synthesis of axially chiral organophosphorus compounds. Mechanistic investigations suggest that the bifunctional phosphonium halide catalyst differentiates between the in-situ-generated P-species in the A-T process, mainly involving phosphoryl chloride and phosphoric anhydride, thus leading to highly enantiodivergent O-phosphorylation reactions. Furthermore hydrogen bonding interactions between the catalysts and phosphorus molecules were crucial in asymmetric induction.
- Chen, Yuan,Fang, Siqiang,Pan, Jianke,Ren, Xiaoyu,Tan, Jian-Ping,Wang, Tianli,Zhang, Hongkui
-
supporting information
p. 14921 - 14930
(2021/05/10)
-
- High performance liquid phase continuous automatic production and co-production technology of organic phosphine compound
-
The invention relates to the field of photocuring functional new material chemicals, and discloses a high performance liquid phase streamline type continuous automatic production technology of an acylphosphine oxide organic phosphine compound for the first time, which not only can produce a single specific target product, but also can co-produce a product mixture of two or more than two of the products of the type. The process technology has outstanding low-cost economic competitiveness and environment-friendly characteristics for large-scale manufacturing of target products. The target product comprises sym-trimethylbenzoyl diphenyl phosphine oxide (also known as 2, 4, 6-trimethylbenzoyl diphenyl phosphine oxide, trade name TPO), sym-trimethylbenzoyl phenyl ethyl phosphonate (trade name TPO-L) and structural analogues thereof, and a mixture of the sym-trimethylbenzoyl diphenyl phosphine oxide and the sym-trimethylbenzoyl phenyl ethyl phosphonate. The organic phosphine compound is an olefinic bond-containing (C=C) unsaturated radiation polymerization system photoinitiator and/or flame retardant and the like with wide application.
- -
-
Paragraph 0070-0076
(2021/05/12)
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- Light-Enabled Radical 1,4-Aryl Migration Via a Phospho-Smiles Rearrangement
-
Rearrangement reactions in organic chemistry are attractive strategies to build efficiently complex scaffolds, in just one step, from simple starting materials. Among them, aryl migrations are certainly one of the most useful and straightforward rearrangement for building attractive carbon-carbon bonds. Of note, anionic aryl migration reactions have been largely described compared to their radical counterparts. Recently, visible-light catalysis has proven its efficiency to generate such radical rearrangements due to the concomitant loss of a particle (often CO2 or SO2), which is the driving-force of the reaction. Here, we disclose a Smiles-type rearrangement, triggered by a phosphorus-containing unit (arylphosphoramidate), therefore called "phospho-Smiles"rearrangement, allowing a Csp2-Csp2 bond formation thanks to a 1,4-aryl migration reaction. In addition, combining this approach with a radical hydroamination/amination reaction produces an amination/phospho-Smiles cascade particularly attractive, for instance, to investigate the synthesis of the phthalazine core, a scarcely described scaffold of interest for medicinal chemistry projects.
- De Abreu, Maxime,Belmont, Philippe,Brachet, Etienne
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p. 3758 - 3767
(2021/02/01)
-
- Chelation-assisted C-N cross-coupling of phosphinamides and aryl boronic acids with copper powder at room temperature
-
A protocol for the chelation-assisted C-N cross-coupling of phosphinamides and aryl boronic acids with copper powder under an oxygen atmosphere is reported. This reaction proceeds efficiently to afford fully substituted unsymmetrical N-arylation phosphinamides at room temperature in excellent yields. Diverse unstable functional groups on the benzene ring of aryl boronic acids such as vinyl, formyl, acetyl, sulfonyl, acetylamino, cyano, nitro, and trifluoromethyl can be accommodated.
- Peng, Yao,Lei, Jian,Qiu, Renhua,Peng, Lingteng,Au, Chak-Tong,Yin, Shuang-Feng
-
p. 4065 - 4070
(2018/06/12)
-
- Direct, oxidative halogenation of diaryl- or dialkylphosphine oxides with (dihaloiodo)arenes
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The oxidative halogenation of diaryl- or dialkylphosphine oxides with the hypervalent iodine reagents (difluoroiodo)toluene (p-TolIF2, 1) and (dichloroiodo)benzene (PhICl2, 2) is reported. Phosphoric fluorides could be recovered in 32–75% yield, or they could be trapped with EtOH to give the corresponding phosphinate in typically good yield. Phosphoric chlorides were not readily isolable, and were trapped with alcohol and amine nucleophiles, giving diaryl- or dialkylphos-phinates and phosphinamides in up to 90% yield.
- Eljo, Jasmin,Murphy, Graham K.
-
supporting information
p. 2965 - 2969
(2018/06/30)
-
- Cobalt-Catalyzed Diastereoselective [4+2] Annulation of Phosphinamides with Heterobicyclic Alkenes at Room Temperature
-
Cobalt-catalyzed sp2 C?H bond functionalization of diarylphosphinamides with heterobicyclic alkenes was demonstrated at room temperature employing commercially available cobalt(II)-salts. The effectiveness of this strategy was illustrated with the reaction of various 8-aminoquinoline derived phosphinic amides and 7-oxa/azabenzonorbornadienes. The reaction conditions exhibited excellent functional group tolerance and high diastereoselectivities. Furthermore, extension of this approach to the preparation of polyaryl cyclic phosphinamides was achieved through the dehydrative ring opening/aromatization sequence. (Figure presented.).
- Nallagonda, Rajender,Thrimurtulu, Neetipalli,Volla, Chandra M. R.
-
supporting information
p. 255 - 260
(2017/11/13)
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- Selective Substitution of POCl 3 with Organometallic Reagents: Synthesis of Phosphinates and Phosphonates
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The selectivity of the substitution reaction of phosphoryl chloride with organometallic reagents was investigated using NMR spectroscopy. This led to the discovery that the selectivity of the substitution reaction can be tuned by choosing a proper organometallic reagent. A phosphinate could be obtained by using a Grignard reagent whereas an organozinc reagent provided a phosphonate. Based on these results, one-pot synthetic methods for the preparation of phosphinates and phosphonates using commercially available starting materials were developed. Both methods allow the synthesis of a broad range of either phosphinate or phosphonate derivatives in a straightforward and general procedure. Moreover, using these one-pot procedures, mixed systems substituted with different alkyl/aryl groups can be prepared.
- Verbelen, Bram,Dehaen, Wim,Binnemans, Koen
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p. 2019 - 2026
(2018/04/14)
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- Rhodium(III)-Catalyzed Enantiotopic C?H Activation Enables Access to P-Chiral Cyclic Phosphinamides
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Compounds with stereogenic phosphorus atoms are frequently used as ligands for transition-metal as well as organocatalysts. A direct catalytic enantioselective method for the synthesis of P-chiral compounds from easily accessible diaryl phosphinamides is presented. The use of rhodium(III) complexes equipped with a suitable atropochiral cyclopentadienyl ligand is shown to enable an enantiodetermining C?H activation step. Upon trapping with alkynes, a broad variety of cyclic phosphinamides with a stereogenic phosphorus(V) atom are formed in high yields and enantioselectivities. Moreover, these can be reduced enantiospecifically to P-chiral phosphorus(III) compounds.
- Sun, Yang,Cramer, Nicolai
-
p. 364 - 367
(2016/12/30)
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- Pd(II)-catalyzed enantioselective synthesis of P-stereogenic phosphinamides via desymmetric C-H arylation
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We present the enantioselective synthesis of P-stereogenic phosphinamides through Pd-catalyzed desymmetric ortho C-H arylation of diarylphosphinamides with boronic esters. The method represents the first example of the synthesis of P-stereogenic phosphorus compounds via the desymmetric C-H functionalization strategy. The reaction proceeded efficiently with a wide array of reaction partners to afford the P-stereogenic phosphinamides in up to 74% yield and 98% ee. The efficiency was further demonstrated by gram scale syntheses. Moreover, the flexible conversion of the P-stereogenic phosphinamides into various types of P-stereogenic phosphorus derivatives was also elaborated. Thus, the protocol provides a novel tool for the efficient and versatile synthesis of P-stereogenic compounds.
- Du, Zhi-Jun,Guan, Jing,Wu, Guo-Jie,Xu, Peng,Gao, Lian-Xun,Han, Fu-She
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p. 632 - 635
(2015/01/30)
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- Synthesis of new organophosphorus compounds using the atherton-todd reaction as a versatile tool
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This article discusses the behavior of seven organophosphorus compounds under Atherton-Todd conditions. Therefore, the reactivity and selectivity of different (phen)oxaphosphinines, dioxaphosphinines, dioxaphosphinanes, and diphenylphosphine oxide with three nucleophiles were systematically studied. The results prove the versatility of the Atherton-Todd reaction to a broad range of organophosphorus compounds with different phosphorus environments and reactive Pi-H bonds. The nucleophiles studied in this article were chosen as model substrates for amines and alcohols. Because organophosphorus molecules are important and versatile compounds, for a broad field of applications, novel synthetic approaches are of interest to both academia and industry. As an example, the single-step synthesis of the bridged 1,3-phenylene bis(diphenylphosphinate) with potential flame-retardant properties was added to this study. In addition, the reaction is utilized for the synthesis of a novel organophosphorus anhydride.
- Wagner, Sebastian,Rakotomalala, Muriel,Bykov, Yana,Walter, Olaf,Doering, Manfred
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scheme or table
p. 216 - 222
(2012/07/13)
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- Thermal stability of phosphinated diethyl tartrate
-
Organohalogen flame retardants, particularly brominated aromatics, are popular, effective, low cost, and widely used in the plastics industry. However, an increasing concern about persistence in the environment and potential negative health effects of these materials has generated intense interest in the development of alternatives. Ideally, these should have all the positive attributes of the materials that will be replaced. In addition, it is desirable that the new materials be as "green" as possible, e.g., based on renewable resources and be degradable to nontoxic products in the environment. A series of new, non-halogenated flame retardants based on tartaric acid is being developed. Tartaric acid is a by-product of the wine industry and is readily available locally on an annual basis (Michigan is the thirteenth largest producer of wine in the U.S.). It can be readily converted to the corresponding diethyl ester. This ester may serve as the base for the development of a series of new, non-halogenated flame-retarding agents. The presence of the reactive hydroxyl groups allows the introduction of a variety of phosphorus-containing moieties. For example, treatment of diethyl tartrate with diphenylphosphinyl chloride generates diethyl 2,3-di(diphenylphosphinato)-1,4-butanedioate. This material may serve as a monomer for the preparation of various phosphorus-containing polymers and oligomers via step-growth transesterification. The thermal stability of this compound has been assessed by thermogravimetry.
- Howell,Carter
-
experimental part
p. 493 - 498
(2011/02/18)
-
- Asymmetric deprotonation-substitution of N-Pop-benzylamines using [RLi/(-)-sparteine]. Enantioselective sequential reactions and synthesis of N-heterocycles
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(Chemical Equation Presented) Pop-directed asymmetric deprotonation of benzylic amines using [n-BuLi/(-)-sparteine] provides an efficient method for the synthesis of chiral NCα and NC α,α′ derivatives with total selectivity with respect to competing allylic and ortho lithiation. The method described herein offers a straightforward route of accessing chiral N-Pop-protected nitrogen heterocycles.
- Ona-Burgos, Pascual,Fernandez, Ignacio,Roces, Laura,Torre-Fernandez, Laura,Garcia-Granda, Santiago,Lopez-Ortiz, Fernando
-
supporting information; experimental part
p. 3195 - 3198
(2009/05/27)
-
- Determination of water content in olive oil by 31P NMR spectroscopy
-
A method for moisture determination in olive oil using 31P NMR spectroscopy is developed. This method is based on the replacement of the hydrogen atoms of water molecules with the tagging agents 2-chloro-4,4,5,5- tetramethyl-1,3,2-dioxaphospholane and diphenylphosphinic chloride. Both reagents were successful in determining moisture in olive oil. However, only the second reagent provided a clean and instantaneous reaction under mild condition with no side reactions as observed with the first reagent. A study comparison was made to assess the agreement between the present analytical NMR method and the well-established methods of Karl Fischer titration.
- Hatzakis, Emmanuel,Dais, Photis
-
experimental part
p. 1866 - 1872
(2009/12/07)
-
- Synthesis of Racemic and Enantiomerically Pure (R*,R*,R* )-Tris(α-methylbenzyl)phosphane - X-ray Crystal Structures of the Phosphane Oxides and Borane Complexes
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An asymmetric synthesis of C3-symmetric phosphane 1 has been achieved. Two of the α-methylbenzyl groups were introduced as nucleophiles (using an α-methylbenzyl Grignard reagent), and asymmetry was introduced by resolution using (R)-α-methylbenzylamine. The final α-methylbenzyl group was introduced as an electrophile (α-methylbenzyl iodide) in a modestly selective reaction. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
- Wyatt, Paul,Eley, Helen,Charmant, Jonathan,Daniel, Berian J.,Kantacha, Anob
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p. 4216 - 4226
(2007/10/03)
-
- Studies on the interaction of phosphine selenides and their structural analogues wth dihalogens and sulfuryl chloride
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The phosphine selenides, tris(dimethylamino)phosphine selenide, esters of selenophosphoric acid, and esters of selenophosphonic acid react with dihalogens and sulfuryl chloride to form halogenoselenophosphonium salts (≡ 3P-SeX)+X-. T
- Krawczyk, Ewa,Skowronska, Aleksandra,Michalski, Jan
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p. 4471 - 4478
(2007/10/03)
-
- Cyclic-acyclic equilibrium and selective P-O bond cleavage in 2-hydroxyphenyldiphenyl-phosphinate, Ph2P(O)OC6H4OH
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The equilibrium in the Ph2P(O)OC6H4OH-base system may be shifted by varying the base concentration, where base = imidazole, triethylamine, dimethyl sulfoxide, pyridine, and 1,4-dioxane. This equilibrium was studied by 31P and 1H NMR, and information about the symmetry of phosphorus-containing intermediates is provided by the 1H NMR spectrum of the catecholyl ring, with its ABCD spin system. The equilibrium is also affected by trifluoroacetic acid. A mechanism is proposed that involves protonation-deprotonation, cyclic-acyclic equilibria, and selective P-O bond cleavage, with all steps occurring rapidly on the NMR time scale.
- Segstro, Edward Paul,Davie, Kerry,Huang, Xiaoling,Janzen, Alexander Frank
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p. 518 - 521
(2007/10/03)
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- POLYSULFONYLAMINE: TEIL LXXI. EIN MOLEKUEL MIT EINER LANGEN Si(sp3)-O-BINDUNG: SYNTHESE, STRUKTUR UND REAKTIVITAET VON N,N-DIMESYLAMIDOSCHWEFELSAEURETRIMETHYLSILYLESTER
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The title compound (MeSO2)2N-SO2-O-SiMe3 (2; m.p. 57 deg C) is obtained by treating (MeSO2)2N-SiMe3 (3) with one equivalent of sulfur trioxide in CH2Cl2 at -20 deg C.The crystal structure of 2 (triclinic, space group P) was established by low-temperature X-ray diffraction.The most interesting feature of the molecular structure is the geometry of the S-O-Si sequence, displaying a very long Si(sp3)-O bond, a short S(sp3)-O bond and a large angle at oxygen (mean values for two independent molecules: Si-O 174.1, S-O 151.1 pm, S-O-Si 134.3 deg).The coordination at nitrogen is trigonal-planar (S-N-S 118.5-121.0 deg, S-N 170.5-173.1 pm). 2 is instantaneously hydrolyzed by excess water to form (MeSO2)2NH, sulfuric acid and (Me3Si)2O.In vacuo at 60 deg C, molten 2 will readily dissociate into its precursors 3 and SO3.It is shown that 2 may react either as an SO3 donor or as a sulfosilylating reagent.Reaction with Lewis bases such as Me3N, pyridine or R2PCl (R = tBu, Ph) proceeds with the formation of the corresponding complexes B*SO3; thermolysis of the isolable phosphane complexes affords the respective phosphane oxides R2(Cl)PO.Sulfosilylation of phenol, cyclohexene or 2,3-dimethyl-2-butene with 2 in CH2Cl2 gives the trimethylsilyl esters of 4-hydroxybenzenesulfonic, cyclohexene-3-sulfonic, or 2,3-dimethyl-1-butene-3-sulfonic acids, respectively.Key words: Trimethylsilyl N,N-dimesylamidosulfonate, synthesis, X-ray structure, long Si(sp3)-O bond, SO3 transfer, sulfosilylation.
- Hiemisch, Oliver,Blaschette, Armand,Jones, Peter G.
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p. 161 - 172
(2007/10/03)
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- The titanium tetrachloride induced synthesis of N-phosphinoylimines and N-sulphonylimines directly from aromatic aldehydes
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The reaction of phosphinic amides or sulphonamides with an aromatic aldehyde in the presence of titanium tetrachloride and triethylamine provides a simple, one-step preparation of N-phosphinoylimines (5a-e) and N-sulphonylimines (7a-g). The extension of this reaction to ketones failed to give the desired imines, the aldol condensation products were obtained instead. The reaction of (+)-camphor with phosphinic amides or sulphonamides in refluxing toluene in the presence of titanium tetrachloride and triethylamine affords the (-)-camphorphosphinoyl- and (-)-camphorsulphonylimines in moderate yield.
- Jennings, W. Brian,Lovely, Carl J.
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p. 5561 - 5568
(2007/10/02)
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- Ozonization: An Efficient Method for the Oxidation of Halophosphines
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The ozonization of various halophosphines 1a-j leads with quantitative yields to the corresponding phosphine oxides 2a-j.Ozonization is a convenient method of oxidation, in particular of compounds with bulky ligands (1c, 1d, 1e).
- Caminade, Anne-Marie,El Khatib, Fayez,Baceiredo, Antoine,Koenig, Max
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p. 365 - 368
(2007/10/02)
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- SILYLPEROXIDES AS SELECTIVE OXYGENATION REAGENTS IN PHOSPHORUS CHEMISRTY
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Bis(trimethylsilyl)peroxide (BSPO) can be used for chemo- and stereoselective generation of P=O group by oxygenation of P(III) centre and transformation of P=S and P=Se groups.
- Kowalski, Jozef,Wozniak, Lucyna,Chojnowski, Julian
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p. 125 - 128
(2007/10/02)
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- Evaluation of Phosphinic Acid Derivatives as Reagents For Amine Protection in Peptide Synthesis
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The results of a kinetic study of the acid-catalysed methanolysis of a series of N-(2-phenyl-ethyl)phosphinamides incorporating selected substituents on phosphorus have been evaluated in order to define the optimum reagent and conditions for amine protection of α-amino acids during peptide synthesis.
- Ramage, Robert,Atrash, Butrus,Hopton, David,Parrot, Maxwell J.
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p. 1217 - 1226
(2007/10/02)
-
- A NOVEL SUBSTITUENT EFFECT ON 31P NMR CHEMICAL SHIFTS IN THE ARYL DIPHENYLPHOSPHINATE SERIES
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The 31P NMR chemical shifts of a series of meta- and para-substituted phenyl diphenylphosphinates, Ph2P(O)OC6H4-X, have been determined.The δ 31P values exhibit an increasing downfield trend as the electron-withdrawing properties of the substituent X become greater and a reasonable correlation between δ 31P and Hammett-Taft substituent constants is obtained.This trend is opposite to that exhibited in several families of compounds of the type ArP(O)Y2, where δ 31P values show an increasing upfield trend as the electron-withdrawing ability of the substituent in Ar is increased.The results are explained by proposing varying degrees of d-orbital occupancy in the phosphorous-oxygen bonds (P-OAr and P=O) in the series of compounds as a factor influencing 31P chemical shifts.
- Hoz, S.,Dunn, E. J.,Buncel, E.,Bannard, R. A. B.,Purdon, J. G.
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p. 321 - 326
(2007/10/02)
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- DIPHENYL(PENTAFLUOROBENZOYLOXY)PHOSPHANOXID UND -SULFID
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Diphenyl(pentafluorobenzoyloxy)phosphane chalcogenides (C6H6)2P(E)(OC(O)C6F5) were prepared by treating AgOC(O)C6F5 with (C6H5)2P(E)Cl ((1)H-, (19)F- und (31)P-NMR- und IR-data).Phosphino-thiono- or phosphino-thiolo-rearrangements are not observed under conditions of synthesis.
- Hennig, Heinz-Werner,Sartori, Peter
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p. 193 - 202
(2007/10/02)
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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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- Carbanionically Induced -Migrations of ?- and Coordinatively Unsaturated Groups
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According to a general reaction scheme, o-lithioaryl esters 4a,b, amides 13a,b 17b, and amidines 39b of non-enolizable carboxylic acids as well as a corresponding diphenylphosphinic amide 51b react under mild conditions to give the intensely coloured lithium derivatives of o-acylphenoles 6a,b and o-acylarenamines 15a,b, 18a, 41a, 52a, which are finally hydrolyzed to the neutral products 7a,b, 14a,b, 18b, 41b, 52b, respectively.The lithiated precursors of the rearrangement are mostly prepared by halogen/metal exchange reactions.In the case of N,N-di-p-tolylpivalamide 33 such a -rearrangement also could be induced by direct metalation of the educt.With N-methyl-N-phenylpivalamide (29), however, exclusive metalation of the N-methyl group occurs, followed by -migration of the pivaloyl group.Silyl groups, too, can undergo analogous -shifts, as was demonstrated by the rearrangement of the o-lithiated N-(trimethylsilyl)aniline 63b to the o-(trimethylsilyl)anilines 65a,b.When a benzoyl and sulfonyl group can compete for the -shifts, as in the N-tosylated benzamide 47b, only the benzoyl group migrates.However, the migration tendency of the trimethylsilyl group equals that of the benzoyl group as was shown with the N-silylated benzamide 66b.
- Hellwinkel, Dieter,Laemmerzahl, Frank,Hofmann, Gunter
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p. 3375 - 3405
(2007/10/02)
-
- DIARYLPHOSPHINIC AZIDES. PHOTOCHEMICAL REACTIONS INCLUDING REARRANGEMENT IN METHANOL
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On photolysis in methanol the diarylphosphinic azides Ar2P(O)N3 (Ar=phenyl, p-tolyl, p-anisyl, p-chlorophenyl) rearrange with loss of nitrogen to form (monomeric) metaphosphonimidates which are trapped by the solvent to give methyl NP-diarylphosphonamidates (7) (41-53percent).Diarylphosphinic amides (18-42percent) are also usually formed, presumably from (triplet) nitrenes.The limited evidence available suggests that the rearrangements take place directly from the photo-excited azides rather than via (singlet) nitrene intermediates.One of the products of rearrangement, methyl NP-di(p-chlorophenyl)phosphonamidate, suffers extensive photochemical dechlorination giving methyl N-phenyl-P-p-chlorophenylphosphonamidate.
- Harger, Martin J.P.,Westlake, Sally
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p. 1511 - 1516
(2007/10/02)
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- Solvation and Catalysis in Displacement at Phosphorus. Reaction of Imidazole and Benzoate Ion with p-Nitrophenyl and 2,4-Dinitrophenyl Diphenylphosphinates
-
The reactions of two phosphorus esters, p-nitrophenyl diphenylphosphinate (I) and 2,4-dinitrophenyl diphenylphosphinate (II), have been investigated in acetonitrile containing variable amounts of water.The effectiveness of imidazole and benzoate ion as catalysts has been investigated.Whereas the reaction of imidazole with II is quite rapid, the reaction with I is very slow.However, I reacts predominantly by the rate term k and shows no k term.Nucleophilic catalysis and the existence of an anhydride intermediate have been confirmed with I by observation of the carbonyl region in the infrared: a C=O peak appropriate for an anhydride appears with C6H5CO2(1-) and then disappears if imidazole is added.This correlates with kinetic evidence for an equilibrium with benzoate ion alone but complete reaction if benzoate and imidazole are both present.The reaction of II has been shown to proceed by reversible formation of 1-(diphenylphosphinyl)imidazole as an intermediate.
- Wallerberg, Gun,Haake, Paul
-
-
- Hydrolysis of Diarylphosphinic Amides in Acidic Solution: Steric Inhibition and Mechanism
-
The pseudo-first-order rate constants for the hydrolysis of diphenylphosphinic amide Ph2P(O)NH2 and its di-p-tolyl, di-o-tolyl, and dimesityl analogues (106kψ 3 630, 2 340, 81.0, and 3.27 s-1 respectively with H(1+) 0.0662M and T 30.2 deg C) in water-dioxan (9:1 v/v) containing perchloric acid show that reaction is sterically hindered by ortho-methyl substituents in the P-aryl groups.Steric inhibition is as great, or greater, in the hydrolysis of the corresponding (N-phenyl)diarylphosphinic amides (106kψ 5 440, 4 470, 54.9 and 0.88 s-1 respectively with H(1+) 1.36M and T 39.9 deg C) and (N-p-nitrophenyldiarylphosphinic amides (106kψ 724, 702, 6.57, and 0.098 s-1 respectively with H(1+) 2.58M and T 39.9 deg C) even though the departing amine is less nucleophilic.Such sensitivity to steric hindrance is consistent with associative (A2) mechanism for the hydrolysis of all the substrates.
- Harger, Martin J. P.
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p. 154 - 160
(2007/10/02)
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- Compound oxidized styrylphosphine
-
Homopolymers, copolymers and terpolymers of a styrene based monomer are prepared by: (1) polymerizing at least one oxidized styrylphosphine monomer selected from the group of: (2) polymerizing p-diphenylphosphinestyrene and then oxidizing said polymerized p-diphenylphosphinestyrene monomer with an organoazide selected from the group of (C6 H5)2 P(O)N3, (C6 H5 O)2 P(O)N3, (C6 H5)2 C3 N3 (N3) and C6 H5 C3 N3 (N3)2. Copolymers can also be prepared by copolymerizing styrene with at least one oxidized styrylphosphine monomer selected from the group of:
- -
-
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- -
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Phosphinous acid esters of the type (R2PO)nER′4-n (E = Si, Ge, Sn) are prepared by three different methods: 1. reaction of the alkali-phosphinites with R′3ECl, 2. reaction of the sec-phosphine oxides with organo
- Issleib,Walther
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p. 375 - 386
(2007/10/05)
-