13360-92-4Relevant articles and documents
Palladacyclic phosphinite complexes as extremely high activity catalysts in the Suzuki reaction
Bedford,Welch
, p. 129 - 130 (2001)
Phosphinite based palladacycles show extremely high activity in the Suzuki coupling of both sterically hindered and electronically deactivated aryl bromides, especially in the presence of one equivalent of free ligand.
A Lewis Base Nucleofugality Parameter, NFB, and Its Application in an Analysis of MIDA-Boronate Hydrolysis Kinetics
Taylor, Nicholas P.,Gonzalez, Jorge A.,Nichol, Gary S.,García-Domínguez, Andrés,Leach, Andrew G.,Lloyd-Jones, Guy C.
supporting information, p. 721 - 729 (2022/01/04)
The kinetics of quinuclidine displacement of BH3 from a wide range of Lewis base borane adducts have been measured. Parameterization of these rates has enabled the development of a nucleofugality scale (NFB), shown to quantify and predict the leaving group ability of a range of other Lewis bases. Additivity observed across a number of series R′3-nRnX (X = P, N; R′ = aryl, alkyl) has allowed the formulation of related substituent parameters (nfPB, nfAB), providing a means of calculating NFB values for a range of Lewis bases that extends far beyond those experimentally derived. The utility of the nucleofugality parameter is explored by the correlation of the substituent parameter nfPB with the hydrolyses rates of a series of alkyl and aryl MIDA boronates under neutral conditions. This has allowed the identification of MIDA boronates with heteroatoms proximal to the reacting center, showing unusual kinetic lability or stability to hydrolysis.
Chemoselective reduction of the phosphoryl bond of O-alkyl phosphinates and related compounds: An apparently impossible transformation
Kenny, Niall P.,Rajendran, Kamalraj V.,Gilheany, Declan G.
supporting information, p. 16561 - 16564 (2015/11/18)
A method is reported for the phosphoryl bond cleavage of O-alkyl phosphinates, phosphinothioates and certain phosphonamidates to furnish the corresponding P(iii) borane adducts. The two-step procedure relies upon initial activation of the phosphoryl bond with an alkyl triflate, followed by reduction of the resulting intermediate using lithium borohydride.
Novel phosphinite and phosphonite copper(I) complexes: Efficient catalysts for click azide-alkyne cycloaddition reactions
Lal, Steven,McNally, Jayne,White, Andrew J. P.,Diez-Gonzalez, Silvia
scheme or table, p. 6225 - 6232 (2012/01/12)
The preparation of novel phosphinite- and phosphonite-bearing copper(I) complexes of the general formula [CuX(L)] is reported. These compounds, which remain scarce in the literature, could be prepared using readily available starting materials and were spectroscopically and structurally characterized. These complexes, together with their known phosphine and phosphite analogues, were then applied to the 1,3-dipolar cycloaddition of azides and alkynes, to find that the new complexes displayed the best activities. Full optimization of the reaction conditions resulted in a noteworthy Click catalytic system, active under very mild reaction conditions in the absence of any additive and using low metal loadings.
Conversion of alcohols to alkyl aryl sulfides by a new type of oxidation-reduction condensation using phenyl diphenylphosphinite
Kuroda, Kiichi,Maruyama, Yuji,Hayashi, Yujiro,Mukaiyama, Teruaki
experimental part, p. 381 - 392 (2009/06/28)
Preparation of alkyl aryl sulfides from alcohols and arenethiols such as 2-sulfanyl-1,3-benzothiazole (BtzSH) is described by a new type of oxidation-reduction condensation using phenyl diphenylphosphinite (PhOPPh 2) and benzoquinone derivatives or azide compounds. This reaction proceeds under mild and neutral conditions and is applicable to the thioetherification of various alcohols in which the chiral secondary and tertiary alcohols are converted into the corresponding chiral sulfides with almost complete inversion of configuration.
Efficient method for the preparation of inverted alkyl carboxylates and phenyl carboxylates via oxidation-reduction condensation using 2,6-dimethyl-1,4-benzoquinone or simple 1,4-benzoquinone
Shintou, Taichi,Fukumoto, Kentaro,Mukaiyama, Teruaki
, p. 1569 - 1579 (2007/10/03)
Oxidation-reduction condensation using in situ formed alkoxydiphenylphosphines, 2,6-dimethy-1,4-benzoquinone, and carboxylic acids provides a useful method for the preparation of inverted tertiary alkyl carboxylates from the corresponding chiral tertiary alcohols under mild and neutral conditions. Similarly, it has afforded alkyl carboxylates successfully in good-to-high yields by the combined use of alkoxydiphenylphosphines having primary, secondary, or tertiary alkoxy groups, carboxylic acids, and simple 1,4-benzoquinone. When chiral secondary or tertiary alcohols are used, the corresponding inverted secondary or tertiary alkyl carboxylates are also obtained in good-to-high yields. In addition, a convenient method for the preparation of phenyl carboxylates in high yields has been established by utilizing oxidation-reduction condensation in toluene at 110 °C using phenoxydiphenylphosphines in situ-formed from phenols and chlorodiphenylphosphine, 2,6-dimethyl-1,4-benzoquinone, and carboxylic acids.
Orthopalladated phosphinite complexes as high-activity catalysts for the suzuki reaction
Bedford, Robin B.,Hazelwood, Samantha L. Welch,Horton, Peter N.,Hursthouse, Michael B.
, p. 4164 - 4174 (2007/10/03)
The synthesis of a range of phosphinite ligands PR2(OAr) (R = Ph, iPr), their simple complexes with palladium(II) and their palladacyclic complexes has been investigated. The crystal structure of one of the palladacyclic complexes, [{Pd(μ2-Cl)} {κ2-P, C-PiPr2(OC6H2-2,4-t Bu2)} 2], has been determined. The palladacyclic complexes show extremely high activity in the Suzuki coupling of aryl bromide substrates with phenylboronic acid and can also be used with alkylboronic acid substrates. A comparison of the phosphinite-based catalysts with equivalent phosphite- and phosphine-based systems highlights their superior activity. The orthometallation of the phosphinite ligand in the pre-catalyst appears to be crucial for optimal activity. While the phosphinite palladacycles are only moderately active in the coupling of activated and non-activated aryl chloride substrates, their tricyclohexylphosphine adducts prove to be highly active in the coupling of the deactivated substrate, 4-chloroanisole. This high activity compared with other palladacyclic systems is explained in terms of catalyst longevity. The orthometallated precatalysts appear to undergo a reductive activation process to generate zerovalent active catalysts via reductive elimination of the orthometallated ring with a phenyl introduced by the boronic acid. This implies that the true active catalysts contain 2-arylated ligands. Catalysts formed with such 2-arylated ligands tend to show markedly higher activity than their parent ligands.
Structural and Electronic Impact of Fluorine in the Ortho Positions of the Phenoxy Groups of Phenyl-phosphonite and -phosphinite Ligands in Compounds of Platinum-group Metals
Atherton, Malcolm J.,Fawcett, John,Hill, Adrian P.,Holloway, John H.,Hope, Eric G.,et al.
, p. 1137 - 1148 (2007/10/03)
The phosphonites PPh(OPh)2 I and PPh(OC6H3F2-2,6)2 II, and the phosphinites PPh2(OPh) III and PPh2(OC6H3F2-2,6) IV reacted with 5-C5Me5))> to yield the complexes 5-C5Me5)> .The perpronito-phosphonite and -phosphinite, I and III, reacted with to yield exclusively the cis isomers of 5 and 7.The fluorine-containing phosphonite and phosphinite, II and IV, reacted with to give the trans isomers of 6a and 8a, which isomerize slowly in acetone solution to yield the cis isomers 6b and 8b.Values of 1J(RhP) and 1J(PtP) strongly suggest that the presence of fluorine atoms in the ortho positions of the phenoxy groups has a negligible effect on the electronic properties of the phosphorus atoms of the ligands.X-Ray single-crystal structural studies on 1, 4, 6a, 7, 8a and 8b revealed that the fluorine atoms do, however, exert a profund steric influence.
