Triethyl Phosphite Research Articles

Synthesis of new α aminophosphonate system bearing Indazole moiety and their biological activity

We are reporting herein for the first time the synthesis of α-aminophosphonates containing Indazole moiety in two steps. In the first step, imines of substituted N-benzylidene-1-methyl-1H-indazole-3-carbohydrazide are synthesized and in the next step it has converted to α-aminophosphonates using chlorotrimethylsilane (TMSCl) and triethyl phosphite. Some of the synthesized derivatives are evaluated for antibacterial activity against different bacterial strains.

Conjugation‐Promoted Reaction of Open‐Cage Fullerene: A Density Functional Theory Study

Density functional theory calculations are performed to study the addition mechanism of e-rich moieties such as triethyl phosphite to a carbonyl group on the rim of a fullerene orifice. Three possible reaction channels have been investigated. The obtained results show that the reaction of a carbonyl group on a fullerene orifice with triethyl phosphite most likely proceeds along the classical Abramov reaction; however, the classical product is not stable and is converted into the experimental product. An attack on a fullerene carbonyl carbon will trigger a rearrangement of the phosphate group to the carbonyl oxygen as the conversion transition state is stabilized by fullerene conjugation. This work provides a new insight on the reactivity of open-cage fullerenes, which may prove helpful in designing new switchable fullerene systems.

A novel approach to isoindolo[2,1-a]indol-6-ones

A convenient route to isoindolo[2,1-a]indol-6-ones has been developed starting from the appropriate 2-(N-phthaloyl)benzoic acids. Formation of the acid chlorides with thionyl chloride followed by heating with triethyl phosphite in a suitable solvent resulted in a multistep reaction giving tetracyclic β-ketophosphonates that on reduction with sodium borohydride gave the required indolones in good overall yields. Analogous β-ketophosphonates were also prepared starting with N,N-(1,8-naphthaloyl)-2-aminobenzoic acid and 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)benzoic acids although of these only the naphthaloyl product could be reduced with sodium borohydride without cleaving the amide bond in the ring system.

CRYSTAL ANALYSIS OF MULTI PHASE CALCIUM PHOSPHATE NANOPARTICLES CONTAINING DIFFERENT AMOUNT OF MAGNESIUM

In this study, Mg doped hydroxyapatite [( Ca , Mg )10( PO 4)6( OH )2] and β-tricalcium phosphate nanoparticles were synthesized via sol gel method. Triethyl phosphite, calcium nitrate tetrahydrate and magnesium nitrate hexahydrate were used as P , Ca and Mg precursors. The ratio of ( Ca + Mg )/ P and the amount of magnesium ( x ) were kept constant at 1.67 and ranging x = 0 up to 3 in molecular formula of Ca 10- x Mg x ( PO 4)6( OH )2, respectively. Phase composition and chemical structure were performed using X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR). Phase percentages, crystallite size, degree of crystallinity and lattice parameters were investigated. The presence of magnesium led to form the Mg doped tricalcium phosphate (β-TCMP) and Mg doped hydroxyapatite ( Mg - HA ). Based on the results of this study, lattice parameters, degree of crystallinity and crystallite size decreased with magnesium content. In addition, with increasing magnesium content, the amount of CaO phase decreased whereas the amount of MgO phase increased significantly. Obtained results can be used for new biomaterials design.

Four-Component Synthesis of Indazole through Ugi-Azide Coupling

ortho-Nitrobenzaldehyde and trimethylsilyl azide were used in a Ugi-Cadogan cascade towards tetrazolyl indazoles. After the Ugi step, the intermediate tetrazoles were not purified but directly heated with triethyl phosphite to form the final indazoles.

ChemInform Abstract: Nickel‐Catalyzed Arbuzov Reactions of Aryl Triflates with Triethyl Phosphite.

AbstractKBr is used as highly efficient additive to produce the synthetically important phosphorus compounds in good to excellent yields.

ChemInform Abstract: Studies on Novel Synthetic Methodologies. Part 220. Metal‐Free Multicomponent Synthesis of (α‐Aminoalkyl)phosphonates Using 2,4,6‐Trichloro‐1,3,5‐triazine.

Abstract(α‐Aminoalkyl)phosphonates (IV) and (VI) are obtained by three‐component reaction of aldehydes, anilines and triethyl phosphite in the presence of trichlorotriazine as mild HCl source.

PEG-SO 3H catalyzed synthesis and cytotoxicity of α-aminophosphonates

One pot three-component PEG-SO 3H catalyzed reaction of 4-(Pyridin-4-yl)benzaldehyde and triethyl phosphite with various primary amines afforded α-aminophosphonates with high yields by the Kabachnik–Field’s reaction. These new structurally diversified set of α-aminophosphonates ( 4a–j) were evaluated for their anti-tumor activity on human chronic myeloid leukemia cells ( K 562), human colon carcinoma cells ( Colo 205) along with non-cancerous human embryonic kidney cells ( HEK 293). They showed moderate activity on both cancerous cells and non-cancerous cells.

Microwave-Enhanced Synthesis of Phosphonoacetamides

An efficient microwave protocol is described for the Michaelis–Arbuzov synthesis of secondary and tertiary N-aryl (and alkyl) (diethylphosphono)acetamides 1, by reaction of chloro- and bromoacetamides with triethyl phosphite in the presence of catalytic amounts of sodium iodide. Remarkable acceleration of the reaction (minutes vs. several hours) over conventional heating was achieved, together with improved product yields and purity, when bromoacetamides were employed as the substrates. Chloroacetamides were comparatively less reactive, leading to satisfactory yields only when a high excess of the reagent was employed.

Electrochemical Synthesis of Organophosphorus Compounds through Nucleophilic Aromatic Substitution: Mechanistic Investigations and Synthetic Scope

AbstractAdvantages of the electrochemical approach in the nucleophilic aromatic substitution reaction, such as (a) low cost and ready availability of reagents, (b) atom economy, and (c) high yields (approaching 100 %), are applied to rationalize the (polar or radical) mechanism and to develop new greener synthetic routes for the synthesis of substituted nitroaromatic organophosphorus compounds. The nucleophiles used to study the feasibility and viability of the reaction are the classical tervalent phosphorus nucleophiles: trimethylphosphane, triethylphosphane, triphenylphosphane, diphenylphosphane, trimethyl phosphite, triethyl phosphite, dimethyl phosphonate, diethyl phosphonate, oxo(diphenyl)phosphorane, with two nitroaromatic compounds 1,3,5‐trinitrobenzene and 1‐chloro‐2,4,6‐trinitrobenzene in a DMF solution containing 0.1 M tetrabutylammonium tetrafluoroborate. In all cases, in order to establish the feasibility or benefits of the electrochemical approach relative to the chemical approach, blank reactions were also performed.

Efficient one-pot synthesis of β-phosphono malonates and 2-amino-4H-chromen-4-ylphosphonate derivatives by ethylenediamine diacetate-catalyzed three-component reactions

One-pot three-component reactions of arylaldehyde or salicylaldehyde with malononitrile (or ethylcyanoacetate) and triethyl phosphite are carried out in the presence of ethylenediamine diacetate (EDDA) as a catalyst for the synthesis of biologically interesting β-phosphono malonates and 2-amino-4H-chromen-4-ylphosphonate derivatives. The value of this method lies in its mild reaction catalyst and conditions, good yields, and ease of handling.

Synthesis, Characterization, and Biological Screening of Some Novel Thiazolidin-4-One and α-Aminophosphonate Derivatives

Synthesis of some new functionalized thiazolidin-4-ones and α-amino phosphonate derivatives has been reported. The imines were synthesized from the reaction of various substituted anilines with 1-phenyl-3-(pyridine-4-yl)-1H-pyrazole-4-carbaldehyde in ethanol at reflux condition. The corresponding thiazolidin-4-ones and α-aminophosphonates were prepared by reaction of imines with mercaptoacetic acid and triethyl phosphite, respectively. The structures of the newly synthesized compounds were confirmed by IR, 1H NMR, and mass spectral data and were evaluated for their antimicrobial activities. GRAPHICAL ABSTRACT

New data on the malonic ester phosphorylation

Phosphorylation reaction of malonic ester so far attracts the researchers attention that is obviously associated with a possibility of its wide chemical modifications for the synthesis of compounds with the practically useful properties. Previously was shown [1] that the reaction of diethyl bromomalonate with triethyl phosphite and the reaction of diethyl chlorophosphate with sodium malonic ester proceed to afford the C-phosphorylation product. DOI: 10.1134/S1070363211100264

ChemInform Abstract: An Expedient Synthesis of Diethyl Diazomethylphosphonate.

A simple three-step preparation of diethyl diazomethylphosphonate was performed from chloroacetone and triethyl phosphite in total yield 70%.

Aqueous-Phase Synthesis of α-Hydroxyphosphonates Catalyzed by β-Cyclodextrin

α-Hydroxyphosphonates were synthesized from aromatic/heteroaromatic aldehydes with triethyl phosphite in the presence of β-cyclodextrin in an aqueous medium. The β-cyclodextrin can be recovered and reused without loss of catalytic activity.

Metal‐Free Multicomponent Synthesis of (α‐Aminoalkyl)phosphonates Using 2,4,6‐Trichloro‐1,3,5‐triazine

Abstract(α‐Aminoalkyl)phosphonates have efficiently been synthesized by multicomponent reaction of aldehydes, amines, and triethyl phosphite in the presence of 2,4,6‐trichloro‐1,3,5‐triazine at room temperature. The products are formed in high yields (83–91%) within 0.5–1 h.

A new conjugated addition of trialkyl phosphites and alkylidenephosphoranes to 3-ω-azideoacetyl coumarin synthesis of some 1,2,3,4-triazaphospholes, triazoles, and azido-coumarin derivatives

A new and efficient conjugate addition of trimethyl and triethyl phosphites to 3-ω-azidoacetylcoumarin (1) has been studied. The reaction proceeded smoothly at r.t. furnishing 1,2,3,4-triazaphosphole coumarin derivatives 4a, 4b in ∼75% yields. Linear substituted triazoles 10b, 11a were also obtained from the reactions of 1 with α-keto ylides, acetyl- and benzoylmethylene triphenylphosphoranes. Contrary to these results, Wittig reaction was occurred when 1 was allowed to react with α-alkoxycarbonylmethylene- and cyanomethylenetriphenylphosphoranes 7c, 7d, 7e as well as with methylidene- and benzylidenetriphenylphosphoranes 8b, 10a resulting in the formation of the corresponding olefins either as an intermediate 14b or as final products 11b, 11c, 12a. J. Heterocyclic Chem., (2011).

Nickel-catalyzed Arbuzov reactions of aryl triflates with triethyl phosphite

An efficient method was developed for the nickel-catalyzed phosphonylation of aryl triflates with triethyl phosphite, in which KBr as an additive promoted the SN2 catalytic step. To the best of our knowledge, this is the first example of nickel-catalyzed Arbuzov reactions of aryl triflates. Most of the substrates showed good reactivity under this catalytic system.

X‐ray structural analysis and theoretical studies of new phosphite‐derived ylides

AbstractThe reaction between dialkyl acetylenedicarboxylates and NH heterocyclic compounds in the presence of triethyl phosphite leads to stable phosphorus ylide derivatives in good yields. The X‐ray crystallographic data and theoretical study show that there is a resonance between two bonds of C19P1 and C191O191 in phosphorus ylide 4d. This compound crystallizes in the orthorhombic system, space group (Pca21), with unit cell parameters a = 17.3699(3) Å, b = 13.5500(2) Å, c = 18.4627(3) Å, α = 90°, β = 90°, γ = 90°, Z = 8, and V = 4345.4(12) Å3. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:715–722, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20739

ChemInform Abstract: Direct Conversion of Benzylic and Allylic Alcohols to Phosphonates.

Benzyl phosphonate esters often serve as reagents in Horner−Wadsworth−Emmons reactions. In most cases, they can be prepared from benzylic alcohols via formation of the corresponding halide followed by an Arbuzov reaction. To identify a more direct synthesis of phosphonate esters, we have developed a one-flask procedure for conversion of benzylic and allylic alcohols to the corresponding phosphonates through treatment with triethyl phosphite and ZnI2.