Methyl Diphenylphosphinite Research Articles

A method for the synthesis of unsymmetric bisphosphoric analogs of α-amino acids.

Herein, we describe the first universal strategy for the synthesis of unsymmetric phosphonyl-phosphinyl and phosphonyl-phosphinoyl analogs of N-protected 1-aminobisphosphonates. The proposed user-friendly procedure, based on a one-pot reaction of the α-ethoxy derivatives of phosphorus analogs of protein and non-protein α-amino acids with triphenylphosphonium tetrafluoroborate and an appropriate phosphorus nucleophile (diethyl phenylphosphonite or methyl diphenylphosphinite), provides good to very good yields of 53-91% under mild catalyst-free conditions (temperature: rt to 40 °C, time: 1 to 6 hours). The progress of the transformation, running through the corresponding phosphonium salt as a reactive intermediate, was monitored by 31P NMR spectroscopy, which is a convenient tool for the identification of the transient species formed here. In this paper, we present the full characteristics of the spectroscopic properties of all 13 synthesized models of structurally diverse N-protected unsymmetric bisphosphoric analogs of α-amino acids. Therefore, these results contribute to increasing the practical applicability of our recently reported synthesis protocol of symmetric models of α-aminobisphosphonates derivatives and thus justify its universality.

Diethyl 1-(N-acetylamino)-1-(diphenylphosphinoyl)-1-phenylmethylphosphonate

Diethyl 1-(N-acetylamino)-1-(diphenylphosphinoyl)-1-phenylmethylphosphonate was synthesized at room temperature, starting from 1-ethoxy derivative of diethyl 1-(N-acetylamino)-1-phenylmethylphosphonate via the corresponding phosphonium salt as a reactive intermediate in the Michaelis–Arbuzov-like reaction with methyl diphenylphosphinite. The structure of the compound obtained was confirmed by spectroscopic techniques (1H, 13C, 31P NMR, IR, and MS).

Synthesis, characterization, and electrochemistry of five diiron propane-1,3-dithiolate complexes with substituted phosphine ligands

In this paper, five diiron propane-1,3-dithiolate complexes containing substituted phosphine ligands were prepared and structurally characterized. Treatment of [Fe2(CO)6(μ-SCH2CH2CH2S)] (1) with a monophosphine ligand methyl diphenylphosphinite, ethyl diphenylphosphinite, 4-(dimethylamino)phenyldiphenylphosphine, tris(2-methoxyphenyl)phosphine, or tris(4-chlorophenyl)phosphine in the presence of Me3NO·2H2O as the decarbonylating agent gave the corresponding phosphine-substituted analogues [Fe2(CO)5(L)(μ-SCH2CH2CH2S)] [L = Ph2POCH3, 2; Ph2POCH2CH3, 3; Ph2P(4-C6H4 NMe2), 4; P(2-C6H4OCH3)3, 5; P(4-C6H4Cl)3, 6] in 73–93% yields. Complexes 2–6 have been characterized by elemental analysis, spectroscopy, and X-ray crystallography. Additionally, electrochemical studies have shown that 2–6 can catalyze the reduction of protons to H2 in the presence of HOAc.

Synthesis and characterization of diiron ethane-1,2-dithiolate complexes with tricyclohexylphosphine, methyl diphenylphosphinite, or tris(2-thienyl)phosphine coligands

We have prepared three diiron ethane-1,2-dithiolate complexes [Fe2(CO)5L(µ-SCH2CH2S)] [L = P(C6H11)3, 2; Ph2POCH3, 3; P(2-C4H3S)3, 4] by CO exchange of the starting complex [Fe2(CO)6(µ-SCH2CH2S)] (1) with the corresponding phosphine ligands tricyclohexylphosphine, methyl diphenylphosphinite, or tris(2-thienyl)phosphine in the presence of Me3NO as an oxidant for CO. The complexes have been characterized by elemental analysis, spectroscopy, and single-crystal X-ray diffraction analysis.

Cover Feature: Unravelling the Enhanced High‐Temperature Performance of Lithium‐Rich Oxide Cathode with Methyl Diphenylphosphinite as Electrolyte Additive (ChemElectroChem 12/2018)

The Cover Feature illustrates the protection effects of the cathodes interfacial layer after adding the methyl diphenylphosphinite (MDP) additive into the electrolyte. MDP participates in the interfacial reaction of cathodes through the peroxidation behavior, and forms a robust protective film with interaction between the P−O species and transition-metal elements. The film prevents the cathodes being attacked by HF in the electrolyte, leading to an enhanced high-temperature performance of lithium-rich oxide cathodes. More information can be found in the Article by Y. Ma and co-workers on page 1569 in Issue 12, 2018 (DOI: 10.1002/celc.201800061).

Unravelling the Enhanced High‐Temperature Performance of Lithium‐Rich Oxide Cathode with Methyl Diphenylphosphinite as Electrolyte Additive

AbstractLithium‐rich oxide cathode materials with high energy density attract much attention, however, they tend to suffer from serious capacity fading during cycling, especially at elevated temperature. Here, methyl diphenylphosphinite (MDP) is studied as electrolyte additive for the first time to enhance the capacity retention of lithium‐rich oxide cathode during cycling under high temperature. As a result, the cyclic stability of Li1.16Ni0.2Co0.1Mn0.54O2 cathodes at elevated temperature is improved significantly when adopting 0.2 wt.% MDP, including an enhanced Columbic efficiency and capacity retention ratio promoted from 49.7 to 93.9 % after 80 cycles. Electrochemical and physical characterizations, combined with theoretical calculations, demonstrate that MDP tends to adsorb on the cathode surfacedue to the interaction between the P−O− species and transition‐metal elements, and then is oxidized preferentially at around 3.75 V (vs. Li/Li+), in situ forming a robust artificial interphase layer on the surface of the cathode. The interphases can effectively inhibit the electrolyte decomposition and greatly enhance the interface stability between Li1.16Ni0.2Co0.1Mn0.54O2 and the electrolyte at high voltage and high temperature.

ChemInform Abstract: Synthesis of Glycosyl Phosphonates and Related Compounds.

The synthesis of glycosylphosphonates, isopolar, nonisosteric analogues of glycosylphosphates, from halonitro ethers, glycosyl acetates, or glycosyl trichloroacetimidates is reviewed. A new approach to phosphonate analogues of myo-inositol trisphosphate (50) is described. Based on a hypothetical reaction mechanism for the formation of thioethers from a glyoxalase I inhibitor, an advanced intermediate 59 for the synthesis of diphosphonate–phosphate analogues of 50 is obtained by an addition–elimination–addition sequence from 54. Finally, glucosylphosphines, characterized as the corresponding phosphine oxides 61 and 62 have been prepared from the glycosylidene diazirine 60, a precursor of the tetra-O-benzylglucopyranosylidene carbene. The phosphine oxides 61 and 62 were also obtained by reaction of the glycosyl acetate 18 with methyl diphenylphosphinite.

ChemInform Abstract: Reactions of Selenothioic Acid S-Esters with Trivalent Phosphorus Compounds: New Synthetic Methods for α-Phosphoryl Alkyl Sulfides and Alkyl Selenides.

The reaction of selenothioic acid S-esters 1 with trialkyl phosphites proceeds smoothly with the extrusion of selenium atoms to afford α-phosphoryl sulfides 2 in good to high yields. A similar reaction takes place more easily with dimethyl phenylphosphonite and methyl diphenylphosphinite, although the ketene selenothioacetals 3 are also formed as by-products in increased yields. The use of diselenoic acid esters 1f and 1g gives α-phosphoryl selenides 2m and 2n. The products exhibit characteristic chemical shifts and coupling constants in their 31P NMR spectra. The structure of α-phosphoryl selenide 2n is confirmed by X-ray molecular structure analysis. The reaction with triphenylphosphine leads to oxidative dimerization of ester 1d to give divinyl diselenide 4 in good yield. A catalytic amount of triphenylphosphine is also effective to form divinyl diselenide 4. The reaction may begin with the nucleophilic attack of triphenylphosphine on the carbon atom of the selenocarbonyl group of ester 1d. Details of the reaction pathway leading to α-phosphoryl sulfides 2 are also discussed. The reaction with menthyl diphenylphosphinite 12 has suggested that the reaction may proceed via initial nucleophilic attack of trivalent phosphorus compounds bearing alkoxy groups on the selenium atom of esters 1. The intermediacy of phosphonium ylide 14 has also been supported by the reaction of the ester 1h which gives 1,4-oxathiane 15.

Cis-Dichloridobis(dimethoxyphenylphosphine)palladium(II)

The title compound, [PdCl2(C8H11O2P)2], has a comparable structure to those of related palladium dichloride complexes containing trimethyl phosphinite and methyl diphenyl phosphinite. The Pd atom is located on a crystallographic twofold rotation axis: thus, there is just one half-mol­ecule in the asymmetric unit. The structure is isomorphous with the platinum analogue cis-[PtCl2{P(OMe)2Ph}2].

The Michaelis–Arbuzov rearrangement of anomeric thiocyanates: synthesis and application of S-glycosyl thiophosphates, thiophosphonates and thiophosphinates as glycosyl donors

Reaction of anomeric thiocyanates with triethyl phosphite, dimethyl phenylphosphonite and methyl diphenylphosphinite afforded the corresponding S-glycosyl thiophosphates, thiophosphonates and thiophosphinates in good yields. These derivatives were applied as glycosyl donors in the synthesis of benzyl glycosides and disaccharides with excellent stereoselectivity.

Synthesis and characterisation of new pyrazole–phosphinite ligands and their ruthenium(II) arene complexes

The new potentially bidentate pyrazole–phosphinite ligands [(3,5-dimethyl-1 H-pyrazol-1-yl)methyl diphenylphosphinite] ( L 1 ) and [2-(3,5-dimethyl-1 H-pyrazol-1-yl)ethyl diphenylphosphinite] ( L 2 ) were synthesised and characterised. The reaction of L 1 and L 2 with the dimeric complexes [Ru(η 6-arene)Cl 2] 2 (arene = p-cymene, benzene) led to the formation of neutral complexes [Ru(η 6-arene)Cl 2(L)] (L = L 1 , L 2 ) where the pyrazole–phosphinite ligand is κ 1- P coordinated to the metal. The subsequent reaction of these complexes with NaBPh 4 or NaBF 4 produced the [Ru(η 6- p-cymene)Cl( L 2 )][BPh 4] and [Ru(η 6-benzene)Cl( L 2 )][BF 4] compounds which contain the pyrazole–phosphinite ligand κ 2- P,N bonded to ruthenium. All the complexes were fully characterised by analytical and spectroscopic methods. The structure of the complex [Ru(η 6- p-cymene)Cl( L 2 )][BPh 4] was also determined by a X-ray single crystal diffraction study.

Reactions of selenothioic acid S-esters with trivalent phosphorus compounds: new synthetic methods for α-phosphoryl alkyl sulfides and alkyl selenides

The reaction of selenothioic acid S-esters 1 with trialkyl phosphites proceeds smoothly with the extrusion of selenium atoms to afford α-phosphoryl sulfides 2 in good to high yields. A similar reaction takes place more easily with dimethyl phenylphosphonite and methyl diphenylphosphinite, although the ketene selenothioacetals 3 are also formed as by-products in increased yields. The use of diselenoic acid esters 1f and 1g gives α-phosphoryl selenides 2m and 2n. The products exhibit characteristic chemical shifts and coupling constants in their 31P NMR spectra. The structure of α-phosphoryl selenide 2n is confirmed by X-ray molecular structure analysis. The reaction with triphenylphosphine leads to oxidative dimerization of ester 1d to give divinyl diselenide 4 in good yield. A catalytic amount of triphenylphosphine is also effective to form divinyl diselenide 4. The reaction may begin with the nucleophilic attack of triphenylphosphine on the carbon atom of the selenocarbonyl group of ester 1d. Details of the reaction pathway leading to α-phosphoryl sulfides 2 are also discussed. The reaction with menthyl diphenylphosphinite 12 has suggested that the reaction may proceed via initial nucleophilic attack of trivalent phosphorus compounds bearing alkoxy groups on the selenium atom of esters 1. The intermediacy of phosphonium ylide 14 has also been supported by the reaction of the ester 1h which gives 1,4-oxathiane 15.

Synthesis and Characterization of Cobalamines with Phosphonito and Phosphinito Ligands

Reactions of aquacobalamine with dimethyl and diphenyl phenylphosphonite and with methyl diphenylphosphinite lead to neutral complexes in which the partially hydrolyzed an ionic ligands [PPh(OR)(O)]- (R = Me, Ph) and [PPh2(O)]- are P-bonded to the cobalt(III) ion of the cobalamine moiety. Hydrolysis of the prochiral phosphonite already coordinated to the chiral cobalamine leads to two diastereomers which are formed in different yields. This optical induction is seen in the 1H and 31P{1H} N M R spectra.

Synthesis of glycosyl phosphonates and related compounds

AbstractThe synthesis of glycosylphosphonates, isopolar, nonisosteric analogues of glycosylphosphates, from halonitro ethers, glycosyl acetates, or glycosyl trichloroacetimidates is reviewed. A new approach to phosphonate analogues of myo‐inositol trisphosphate (50) is described. Based on a hypothetical reaction mechanism for the formation of thioethers from a glyoxalase I inhibitor, an advanced intermediate 59 for the synthesis of diphosphonate–phosphate analogues of 50 is obtained by an addition–elimination–addition sequence from 54. Finally, glucosylphosphines, characterized as the corresponding phosphine oxides 61 and 62 have been prepared from the glycosylidene diazirine 60, a precursor of the tetra‐O‐benzylglucopyranosylidene carbene. The phosphine oxides 61 and 62 were also obtained by reaction of the glycosyl acetate 18 with methyl diphenylphosphinite.

Reduction of nitro- and nitroso-compounds by tervalent phosphorus reagents. Part 16. Formation and reactions of 2,3-dihydro-1,3,2-benzothiazaphosph(V)oles [amino(thiyl)phosphoranes

In contrast to the corresponding ethers, which give 3-aryl-2,3-dihydro-1,3,2-benzoxazaphosph(V)oles [amino(oxy)phosphoranes](1; X = O) on reaction with phosphorus(III) esters, aryl 2-nitroaryl sulphides give N-aryl-N(2-alkylthiophenyl)phosphoramidates (4). In addition to N–S heterocycles. Yields of (4) are high (70%) when O-blocking methyl groups are present. Using 31P Fourier-transform n.m.r. spectroscopy we have shown that compounds (4) are probably derived via the intermediacy and isomerisation of amino (thiyl)phosphoranes (1; X = S). This has been confirmed, using 2-phenyl-1,3,2-dioxaphospholan, by the isolation of the novel 2,3-dihydro-2-phenyl-3-(2,4,6-trimethylphenyl)-1,3,2-benzothiazaphosph(V)ole-2-spiro-2′-1′,3′,2′-dioxaphospholan (6; Q = Y = Me) and its 2,6-dimethylphenyl- and 2,6-dimethoxyphenyl-analogues (6; Q = Me, Y = H and 6; Q = MeO, Y = H) in 32–76% yield. These do not isomerise to amidates corresponding to (4). The use of methyl diphenylphosphinite (Ph2POMe) in boiling toluene led to the first monocyclic amino (thiyl)phosphoranes, 2,3-dihydro-2,2-diphenyl-3-(2,6-dimethylphenyl)-2-methoxy-1,3,2-benzothiazaphosph(V)ole (7 Ar = 2,6-Me3C6H3; 51%) and its 2,4.6-trimethylphenyl analogue (7; Ar = 2,4,6-Me2C6H2; 48%). In boiling cumene (153 °C) these isomerised into N-(2,6-dimethylphenyl)-N-(2-methylthiophenyl)-PP-diphenylphosphinamidate (8) and its trimethylphenyl analogue. A kinetic study, using a programmed n.m.r. technique, showed that this reaction is first order (105k1 at 451 K = 2.4 ± 1.2 s–1), the high activation energy (Eact. 220 ± 60 kJ mol–1) pointing to a rate-determining fission of the phosphorane ring to give a quasi-phosphonium betaine (10), followed by fast alkyl transfer.

ChemInform Abstract: PHOSPHORUS‐CONTAINING HETEROCYCLES FROM PHOSPHORUS(III) REAGENTS AND ORTHO‐AZIDOAROMATIC COMPOUNDS‐ SYNTHESIS OF 2,2‐DI(DIMETHYLAMINO)‐1,3,2‐BENZOXAZAPHOSPHOLE AND VARIOUS 2,3‐DIHYDRO‐1,3,2‐BENZOXAZAPHOSPH(V)OLES

AbstractDas Oxazaphosphol (III) entsteht aus o‐Azidophenol (I) und dem Phosphorester (II), es ist auch aus o‐Aminophenol, N‐Chlordiisopropylamin und (II) zugänglich.

Phosphorus-containing heterocycles from phosphorus(III) reagents and ortho-azidoaromatic compounds: synthesis of 2,2-di(dimethylamino)-1,3,2-benzoxazaphosphole and various 2,3-dihydro-1,3,2-benzoxazaphosph(V)oles

o-Azidophenol reacts with methyl diphenylphosphinite to give the amino(oxy)phosphorane, 2-methoxy-2,2-diphenyl-2,3-dihydro-1,3,2-benzoxazaphosph(V)ole (1; 90%), which is also produced (55%) from o-aminophenol, the phosphinite, and N-chlorodi-isopropylamine; o-azidophenyl benzoate reacts with hexa-methylphosphorous triamide to give 2,2-di(dimethylamino)-1,3,2-benzoxazaphosphole (2; 76%) and NN-dimethylbenzamide.

Reactions of carbonyl compounds with tervalent phosporus reagents. Part 8. Acetyldiphenylphosphine oxide

Detailed spectra are described for acetyldiphenylphosphine oxide (1), prepared as a crystalline solid from acetyl chloride and methyl diphenylphosphinite. The oxide (1) is a potent acylating agent and readily undergoes carbonyl addition reactions. Acetoxydiphenylphosphine and (1) interconvert spontaneously, and then slowly form a dimer.

Reactions of carbonyl compounds with tervalent phosphorus reagents. Part 9. Benzaldehyde with phosphinites in the presence of acetic acid

Acylals (8) are produced by the reaction of benzaldehyde with methyl diphenylphosphinite (4a) and carboxylic acids. One diastereoisomer of (8) is formed almost exclusively under mild conditions; the reasons for this are discussed. α-(α-Acetoxybenzyloxy)benzyldiphenylphosphine oxide (8a) is relatively inert to methanol. Analogues of (8), the 3-acyloxy-1,3-diphenylpropylphosphine oxides (9), have been synthesised and used in assignment of structure to the acylals (8).

A new bicyclic phosphorane

Reaction of 2-hydroxycinnamic acid with methyl diphenylphosphinite (2) yields an unusual bicyclic acyloxyphosphorane (1).