- Facial conversion of secondary phosphine oxides R1R2P(O)H to chlorophosphines R1R2PCl by acetyl chloride
-
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
-
supporting information
(2020/01/03)
-
- Palladium-Catalyzed C-O Cross-Coupling of Primary Alcohols
-
Two catalyst systems are described, which together provide mild and general conditions for the Pd-catalyzed C-O cross-coupling of primary alcohols. For activated substrates, such as electron-deficient aryl halides, the commercially available ligand L2 promotes efficient coupling for a variety of alcohol nucleophiles. In the case of unactivated electrophiles, such as electron-rich aryl halides, the new ligand L8 was developed to improve these challenging C-O bond-forming reactions.
- Zhang, Hong,Ruiz-Castillo, Paula,Buchwald, Stephen L.
-
supporting information
p. 1580 - 1583
(2018/03/23)
-
- Symmetrical and unsymmetrical diphosphanes with diversified alkyl, aryl, and amino substituents
-
We present the comprehensive study of diphosphanes with diversified substituents regarding their syntheses, structures, and properties. To this end, we have synthesized a series of novel unsymmetrical alkyl, aryl and amino-substituted diphosphanes of the general formula R1R2P-PR3R4 (where R1, R2, R3, R4 = tBu, Ph, Et2N or iPr2N) via a salt metathesis reaction of halophosphanes with metal phosphides in high yield. We vastly expanded this group of compounds by obtaining the first mono- A nd tri-amino-substituted systems. The structures of the isolated compounds were characterized by NMR spectroscopy and X-ray diffraction. The isolated unsymmetrical diphosphanes have no tendency to rearrange to the corresponding symmetrical species. Additionally, we proposed the general classification of diphosphanes based on the number of different groups attached to phosphorus atoms and their distribution within a molecule. To investigate the impact of substituents on the properties of P-centers and a molecule as a whole, we conducted a DFT study on the electronic and steric properties of the obtained systems. The experimental and theoretical results can be very useful for designing P-P systems with desired properties.
- Szynkiewicz, Natalia,Ponikiewski, ?ukasz,Grubba, Rafa?
-
supporting information
p. 16885 - 16894
(2019/01/03)
-
- The reactivity of arylphosphorus acid amides under Birch reduction conditions
-
Several classes of arylphosphorus acid amides have been tested in reactions with alkali metal solutions in liquid ammonia. The outcomes of such reactions depend on the structures of the starting materials. Generally, two processes-Birch reduction or cleavage of the P-aryl bond-can be operative. Diarylphosphinic amides tend to undergo double Birch reduction to afford bis(cyclohexadienyl)phosphinic amides. Copyright
- Stankevic, Marek,Wlodarczyk, Adam,Nieckarz, Damian
-
p. 4351 - 4371
(2013/07/26)
-
- Simple unprecedented conversion of phosphine oxides and sulfides to phosphine boranes using sodium borohydride
-
A variety of phosphine oxides and sulfides can be efficiently converted directly to the corresponding phosphine boranes using oxalyl chloride followed by sodium borohydride. Optically active P-stereogenic phosphine oxides can be converted stereospecifically to phosphine boranes with inversion of configuration by treatment with Meerwein's salt followed by sodium borohydride.
- Rajendran, Kamalraj V.,Gilheany, Declan G.
-
supporting information; scheme or table
p. 817 - 819
(2012/02/03)
-
- Reactivity of allyl anions of allylphosphine-boranes towards electrophiles
-
The reactivity of mesomeric carbanions derived from allylphosphine-boranes varies as a function of electrophile. Small sp3-electrophiles react predominantly at the α carbon atom whereas bulky sp3- electrophiles and carbonyl compounds react mainly at the γ carbon. In the case of electron-deficient aldehydes reduction of carbonyl group and formation of the corresponding alcohols is observed. This is attributed to the weakly reducing properties of carbanions derived from allylphosphine-boranes, whose mesomeric form resembles the structure of a modified borohydride. ARKAT-USA, Inc.
- Stankevic, Marek,Siek, Marcin,Pietrusiewicz, K. Michal
-
experimental part
p. 102 - 126
(2011/06/20)
-
- Highly efficient reusable polymer-supported Pd catalysts of general use for the Suzuki reaction
-
Short and efficient syntheses of various polymer-supported Pd catalysts are reported. The reactivity of these catalysts has been determined for the Suzuki reaction. It turned out that the (tert-butylphenylphosphinomethyl)polystyrene-supported Pd catalyst 2′a is highly efficient for versatile Suzuki reactions from aryl chlorides. These couplings are performed in the presence of low amounts (4 mequiv) of supported Pd, the catalyst can be reused more than seven times without loss of efficiency and the Pd leaching is extremely low (0.1% of the initial amount).
- Schweizer, Stéphane,Becht, Jean-Michel,Le Drian, Claude
-
experimental part
p. 765 - 772
(2010/09/07)
-
- Conjugate phosphination of cyclic and acyclic acceptors using Rh(I)-phosphine or Rh(I)-carbene complexes. Probing the mechanism with chirality at the silicon atom or the phosphorus atom of the Si-P reagent
-
The Rh(I)-catalyzed conjugate phosphinyl transfer from an Si-P reagent to an electron-deficient acceptor requires individual protocols for cyclic and acyclic α,β-unsaturated carbonyls and carboxyls. While 1,4-addition to cyclic acceptors is catalyzed by a
- Trepohl, Verena T.,Fr?hlich, Roland,Oestreich, Martin
-
scheme or table
p. 6510 - 6518
(2011/02/26)
-
- Synthesis of building blocks for the development of the SUPRAPhos ligand library and examples of their application in catalysis
-
We have previously introduced the SUPRAPhos ligand library, which is based on components that are self-assembled through nitrogen-zinc interactions, and report here an extension of this library, which widens the scope for application in asymmetric homogeneous catalysis. For example, we report the synthesis of phosphorus amidite appended porphyrins and building blocks with stereogenic centers at the phosphorus. With the new building blocks described in this paper we can form a 450-membered SUPRAPhos library, which is based on 45 building blocks (30 pyridyl phosphorus ligands and 15 complementary porphyrin-appended phosphorus ligands). Examples of the use of members of the library in the rhodium-catalyzed asymmetric hydroformylation of styrene are included. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
- Goudriaan, P. Elsbeth,Jang, Xiao-Bin,Kuil, Mark,Lemmens, Renske,Van Leeuwen, Piet W. N. M.,Reek, Joost N. H.
-
body text
p. 6079 - 6092
(2009/05/31)
-
- Highly efficient and reusable supported Pd catalysts for Suzuki-Miyaura reactions of aryl chlorides
-
Syntheses of air- and moisture-stable heterogeneous (tert- butylarylphosphino)polystyrene-supported Pd catalysts and their use for versatile Suzuki-Miyaura reactions of aryl chlorides and arylboronic acids under non-anhydrous conditions are reported. The catalysts are easily recovered by filtration. They can be used many times (more than seven) without showing any loss of activity, and the amount of Pd leached is extremely low (0.1%).
- Schweizer, Stephane,Becht, Jean-Michel,Le Drian, Claude
-
p. 3777 - 3780
(2008/02/12)
-
- Synthesis of P-stereogenic phosphorus compounds. Asymmetric oxidation of phosphines under appel conditions
-
Racemic phosphines are converted into enantioenriched phosphine oxides via a synthetically simple, but theoretically interesting, oxidation procedure in good enantiomeric excess (up to 80%) and excellent yields (>95%). These phosphine oxides can be oxidatively coupled to provide easy access to enantiopure DiPAMPO analogues. Particularly attractive aspects of this procedure are the operational simplicity and the low cost required to synthesize these high value compounds. Copyright
- Bergin, Enda,O'Connor, Cormac T.,Robinson, Shane B.,McGarrigle, Eoghan M.,O'Mahony, Colm P.,Gilheany, Declan G.
-
p. 9566 - 9567
(2008/02/13)
-
- Chromatographic resolution, solution and crystal phase conformations, and absolute configuration of tert-butyl(dimethylamino)phenylphosphine-borane complex
-
The enantiomers of tert-butyl(dimethylamino)phenylphosphine-borane complex 2 have been separated by HPLC using cellulose tris-p-methylbenzoate as chiral stationary phase. The borane protection could be removed without racemization and the P-configuration
- Naubron, Jean-Valere,Giordano, Laurent,Fotiadu, Frederic,Buergi, Thomas,Vanthuyne, Nicolas,Roussel, Christian,Buono, Gerard
-
p. 5586 - 5593
(2007/10/03)
-
- Mechanism-based design of a ROMP catalyst for sequence-selective copolymerization
-
(Chemical Equation Presented) Back and forth like a metronome is how the carbene moiety swings in a dual-site catalyst which produces a predominantly alternating copolymer of norbornene and cyclooctene from a one-pot reaction of appropriate mixtures of th
- Bornand, Marc,Chen, Peter
-
p. 7909 - 7911
(2007/10/03)
-
- P-chiral phosphinoselenoic chlorides and phosphinochalcogenoselenoic acid esters: Synthesis, characterisation, and conformational studies
-
(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.
- Kimura, Tsutomu,Murai, Toshiaki
-
p. 952 - 959
(2007/10/03)
-
- Process for preparing tertiary phosphines
-
The invention relates to a process for synthesizing tertiary phosphines by reacting halophosphines with organomagnesium compounds in the presence of copper compounds and optionally of salts.
- -
-
-
- Organic phosphorus compounds 106.1 a 31P-NMR study of phosphinous-, phosphinic-, and thiophosphinic amides
-
The synthesis, physical, chemical and spectroscopic properties of eight different types of phosphinous-, phosphinic-and thiophosphinic amides are reported. It is shown that the 31P-chem. shifts of tertiary amides are at lower magnetic field than that of secondary amides. As an exception, in the bis(tertiary butyl) series this trend is reversed.
- Maier, Ludwig,Diel, Peter J.
-
p. 273 - 300
(2007/10/03)
-
- o-Hydroxyarylphosphines and diphosphines: Metallation-rearrangement versus P-O reduction of o-halogenoaryloxyphosphines by sodium
-
o-Bromo-and o-chloroaryloxyphosphines 1 may react with sodium in two competing ways: (i) metal halogen exchange followed by rapid intramolecular 1,3-rearrangement to give sodium o-hydroxylato-arylphosphines 2, later converted to their OSiMe3 de
- Heinicke, Joachim,Kadyrov, Renat
-
p. 131 - 137
(2007/10/03)
-
- Unsymmetrically Substituted Phosphino Sulfur Diimides - NMR Studies on the Configuration in Solution
-
The phosphino-substituted sulfur diimides S(N-Pt-Bu2)2 (1), t-Bu2P(NSN)PRR' (R = R' = phenyl (2a), cyclohexyl (2b), isopropyl (2c), ethyl (2d); R = phenyl, R' = tert-butyl (2e)) and t-Bu2P(NSN)t-Bu (3) were studied in solution by 1H, 13C and 31P NMR spectroscopy.The coupling constants 4J(31P31P) of the compounds containing different phosphino groups, 2a-e, depend both on the nature of the solvent and the temperature.The NMR results are interpreted in accord with a rapid Z/EE/Z interconversion at room temperature and the predominance of a single configurational isomer at low temperatures.There is no indication for the presence of the "symmetrical" configurations, Z/Z or E/E respectively, in solution in appreciable amounts. 15N NMR data are also reported for a series of sulfur diimides. - Keywords: Phosphino-Substituted Sulfur Diimides, 15N NMR Spectra, 31P NMR Spectra, Configurational Isomerism of Sulfur Diimides
- Herberhold, Max,Frank, Stefan M.,Wrackmeyer, Bernd
-
p. 985 - 992
(2007/10/02)
-