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Showing papers in "Phosphorus Sulfur and Silicon and The Related Elements in 2004"


Journal ArticleDOI
TL;DR: In this paper, the synthesis, characterization, and crystal structure of a Ca salt of AMP (AMP = Amino-tris-Methylene Phosphonate) is reported.
Abstract: Organic (poly)phosphonates are additives in water treatment that find broad use as mineral scale and corrosion inhibitors for a plethora of industrial applications. The phenomenon of precipitation of scale inhibitors has been studied intensively. This study reports the synthesis, characterization, and crystal structure of a Ca salt of AMP (AMP = Amino-tris-Methylene Phosphonate). Ca-AMP crystals are monoclinic, space group P 2 1 n with unit cell dimensions, a = 11.3382(5) A, b = 8.4555(4) A, c = 15.5254(7) A, β = 90.6551 o , V = 1488.33(12) A 3 and Z = 4. The structure is polymeric due to chelation of multiple Ca ions by AMP. The Ca 2 + center is slightly distorted octahedral and is surrounded by five phosphonate oxygens and a water molecule. CaO(P) bond lengths range from 2.2924(14) to 2.3356(14) A. The CaO(H 2 O) bond distance is 2.3693(17). Each phosphonate group is monodeprotonated, and the nitrogen atom is protonated. CaCO 3 inhibition and crystal modification by AMP are also reported, together with ...

119 citations


Journal ArticleDOI
TL;DR: In this paper, the design and synthesis of stable heterocyclic thiazyl radicals with a view to generating stable, crystalline materials with a high W/U ratio is presented.
Abstract: The use of neutral π-radicals as building blocks for molecular conductors holds both appeal and challenge. Such systems obviate the need for counterions, as charge transfer is not required to generate charge carriers. Essentially an array of π-radicals should function like atoms in an elemental metal, e.g., sodium, affording a half-filled energy band. Most radicals, however, tend to dimerize, and even when association can be suppressed the resulting low bandwidth W, coupled with a high on-site Coulomb repulsion U, leads to a Mott insulating state. We are pursuing the design and synthesis of stable heterocyclic thiazyl radicals, with a view to generating stable, crystalline materials with a high W/U ratio. The search for these new radicals, the molecular analogues of sodium, is the subject of this presentation.

58 citations


Journal ArticleDOI
TL;DR: In this article, the reaction of polymethylene diamine with aroyl chloride and ammonium thiocyanate under the condition of solid-liquid phase-transfer catalysis using polyethylene glycol-400 (PEG-400) as the catalyst yielded polymethylenes-bis-aroyl thiourea derivatives 3a-q in good-to-excellent yield.
Abstract: Reaction of polymethylene diamine with aroyl chloride and ammonium thiocyanate under the condition of solid–liquid phase-transfer catalysis using polyethylene glycol-400 (PEG-400) as the catalyst yielded polymethylene-bis-aroyl thiourea derivatives 3a–q in good-to-excellent yield. The products have been characterized by analytical and spectral (IR and H1 NMR) data.

55 citations


Journal ArticleDOI
TL;DR: A facile synthesis and studies on the stereochemistry and biochemical aspects of some organosilicon(IV, organotin(IV), and manganese(II) complexes derived from imine having N∪N∪O donor system is reported in this paper.
Abstract: A facile synthesis and studies on the stereochemistry and biochemical aspects of some organosilicon(IV), organotin(IV), and manganese(II) complexes derived from imine having N∪N∪O donor system is reported. The imine was prepared by the condensation of salicylanilide with sulphathiazole. This imine reacts with organosilicon(IV)chloride, organotin(IV)chloride, and hydrated manganese(II) chloride to yield compounds having M─O and M←N bonds. The structures of the compounds have been elucidated by physicochemical and spectral (IR, 1H NMR, 13C NMR, 29Si NMR, 119Sn NMR, and ESR) studies, which clearly point to a trigonal bipyramidal geometry around silicon(IV) and tin(IV), and tetrahedral geometry around manganese(II), as the active lone pair of the nitrogen is also included in the coordination sphere. In the search for better fungicides and bactericides, studies were conducted to assess the growth-inhibiting potential of the synthesized complexes against various pathogenic fungal and bacterial strains. These co...

54 citations


Journal ArticleDOI
TL;DR: The field of high polymers has developed into a large area of more than 700 different types of macromolecules with novel combinations of properties and diverse applications as mentioned in this paper, and small-molecule phosphazene rings have played a major role in these developments.
Abstract: The field of phosphazene high polymers has developed into a large area of more than 700 different types of macromolecules with novel combinations of properties and diverse applications. Small-molecule phosphazene rings have played a major role in these developments, first as starting materials for polymer synthesis, second as synthetic and structural models for the high polymers, and third as components of hybrid inorganic-organic macromolecules. These three aspects are reviewed, with examples taken from our recent work, together with some thoughts on the development of this and related fields in the future.

44 citations


Journal ArticleDOI
TL;DR: H 3 PMo 12 O 40 · xH 2 O was found to be an effective catalyst for the preparation of bis-indolyl derivatives from indole and aromatic, aliphatic, heterocyclic aldehydes or ketones in ethanol at room temperature.
Abstract: H 3 PMo 12 O 40 · xH 2 O was found to be an effective catalyst for the preparation of bis-indolyl derivatives from indole and aromatic, aliphatic, heterocyclic aldehydes or ketones in ethanol at room temperature.

41 citations


Journal ArticleDOI
TL;DR: This review presents methods developed for the synthesis of derivatives of chromone and coumarin that contain a phosphonate moiety, and the reaction of derivative of 2-hydroxyacetophenone with phosphonic compounds is the one most frequently used.
Abstract: Chromone and coumarin derivatives exhibit a wide spectrum of biological activity, including spasmolytic, antiarrhythmic, cardiothonic, antiviral, and anticancer properties. Phosphorus-containing chromone and coumarin derivatives form a novel group of compounds, possessing remarkable cytotoxicity and alkylating and anticancer activity against selected tumor cell lines. Derivatives containing a phosphorus atom at position 2 of a γ-pyrone ring are known to be efficient antibacterial agents. This review presents methods developed for the synthesis of derivatives of chromone and coumarin that contain a phosphonate moiety. Among them, the reaction of derivatives of 2-hydroxyacetophenone with phosphonic compounds is the one most frequently used. Some analogues were characterized by X-ray crystallography.

39 citations


Journal ArticleDOI
TL;DR: Silica phosphoric acid was prepared via reaction of silica chloride (I) and phosphoric acids as mentioned in this paper, which can be readily converted to their corresponding thionitrites with a combination of Silica Pimentoric Acid (II), wet SiO 2, and sodium nitrite in dichloromethane at room temperature.
Abstract: Silica phosphoric acid was prepared via reaction of silica chloride (I) and phosphoric acid. Thiols can be readily converted to their corresponding thionitrites with a combination of silica phosphoric acid (II), wet SiO 2 , and sodium nitrite in dichloromethane at room temperature. Disulfides result from the homolytic cleavage of the sulfur–nitrogen bond of the unstable thionitrite and subsequent coupling of the resultant thiyl radicals.

39 citations


Journal ArticleDOI
TL;DR: A series of new spiro compounds synthesized by the one-pot environmentally benign microwave induced technique involving the cyclocondensation of 3-arylimino-2H-indol-2-ones have been screened in vitro for antifungal activity against Rhizoctonia solani, Fusarium oxysporum, and Collectotrichum capsici, and antitubercular acivity against Mycobacterium tuberculosis.
Abstract: A series of new spiro[3H-indole-3,2′-thiazolidine]-2,4′(1H)-diones (IV) and spiro[3H-indole-3,2′-tetrahydro-1,3-thiazine]-2,4′(1H)-diones (V) have been synthesized in 85–93% yield by the one-pot environmentally benign microwave induced technique involving the cyclocondensation of 3-arylimino-2H-indol-2-ones (III) with thioacids viz. mercapto aceticacid (a)/3-mercapto propionicacid (b) using montmorillonite KSF as inorganic solid support. Intermediates (III) were synthesized in situ by the reaction of indole-2,3-diones (I) and substituted anilines (II). The spiro compounds have been further subjected to solvent-free acetylation, aminoalkylation and thiation under microwave irradiation using solid supports. The synthesized compounds have been screened in vitro for antifungal activity against Rhizoctonia solani, Fusarium oxysporum, and Collectotrichum capsici, and antitubercular acivity against Mycobacterium tuberculosis.

36 citations


Journal ArticleDOI
TL;DR: In this article, the synthesis of a series of 1,2,4-triazolo[3, 4-b]thiadiazoles 5 starting from 4-amino-3-substituted-5-mercapto-1, 2,4 -triazoles 3 and fluorobenzoic acids 4 using phosphorous oxychloride as cyclizing agent.
Abstract: 3-Substituted-4-amino-5-mercapto-1,2,4-triazoles are versatile synthons for constructing various biologically active heterocycles. Their cyclization with carboxylic acids gives fused five-membered derivatives, whereas with α-bromoketones gives a six-membered heterocycle. In this article we report the synthesis of a series of 1,2,4-triazolo[3,4-b]thiadiazoles 5 starting from 4-amino-3-substituted-5-mercapto-1,2,4-triazoles 3 and fluorobenzoic acids 4 using phosphorous oxychloride as cyclizing agent. Fourteen of the newly synthesized compounds were screened for anticancer properties. Four among them showed in vitro anticancer activity.

35 citations


Journal ArticleDOI
TL;DR: In this article, it was shown that microwave catalyzes conversion of the stabilized phosphorus ylides to corresponding coumarins in the presence of silica gel powder in solvent-free conditions.
Abstract: Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, by phenols (1-hydroxynaphthalene, 2-hydroxynaphthalene and 4-bromophenol) leads to vinyltriphenylphosphonium salts, which undergo aromatic electrophilic substitution reaction with conjugate base to produce corresponding stabilized phosphorus ylides. Microwave was found to catalyze conversion of the stabilized phosphorus ylides to corresponding coumarins in the presence of silica gel powder in solvent-free conditions.

Journal ArticleDOI
TL;DR: In this article, the NMR and mass spectral data are given for all products of 1-amino-1-heteroaryl derivatives of diethyl phosphite to the corresponding benzhydryl imines, and the presence of chiral α-carbon and prochiral phosphorus gives rise to complicated features in their NMR spectra.
Abstract: n-Benzhydryl-protected diethyl[3.3pc] esters of 1-amino-1-aryl- (phenyl, cumyl, p-dimethylaminophenyl, piperonyl, 1′-naphthyl, 9′-anthryl, 1′-pyrenyl) and 1-amino-1-heteroaryl- (furyl, 2′-thienyl, 3′-thienyl, 2′-pyrrolyl)-methanephosphonic acids, prepared by the addition of diethyl phosphite to the corresponding benzhydryl imines, have been isolated, purified, and characterized. The presence of chiral α -carbon and prochiral phosphorus in these esters gives rise to complicated features in their NMR spectra, which are discussed. Hydrolysis of the crude 1-aryl compounds in situ gave modest yields of the corresponding aminophosphonic acids (except for 1′-pyrenyl). Of the 1-heteroaryl derivatives, only the 2′-thienyl compound gave the expected aminophosphonic acid; in other cases, alternative[-18pc] modes of decomposition may occur under hydrolytic conditions. NMR and mass spectral data are given for all products.

Journal ArticleDOI
TL;DR: In this article, the carbon diphosphine complexes of type (A) which form four heteromemebered rings and/or type (B) which react (addition reaction) with some different amines (methyl amine, dimethyl amine), phenyl hydrazine and or some of amino acids (glycine, alanine, aspartic acid, serene).
Abstract: Interaction of [Ph2PC(═CH2)PPh2] (A)1–3 and/or [Ph2P (CH═CH) PPh2](B) ligands in different molar ratio with hexacarbonyl metals M(CO)6 gives [M(CO) n Ph2PC(═CH2)PPh2] and/or [M(CO) n Ph2P (CH═CH)PPh2 where M═ Cr, Mo or W, n = 2 and/or 4]. The carbon diphosphine complexes of type (A) which form four heteromemebered rings and/or type (B) form five heteromembered rings which reacts (addition reaction) with some different amines (methyl amine, dimethyl amine), phenyl hydrazine and/or some of amino acids (glycine, alanine, aspartic acid, serene). The structures of A and/or B complexes and their amino derivatives have been characterized by using elemental analysis, IR spectra, 1HNMR,1H-31P-NMR, and mass spectra. Ligands and their complexes were screened in vitro to investigate the biological activities (antibacterial and antifungi). Interestingly, complexes are having strong and remarkable activities increases than the free ligands.

Journal ArticleDOI
TL;DR: In this article, the reactivity of 1-(2,4-dimethoxyphenyl)-3-aryl-2-propen-1-ones (Ia&b) under different conditions, towards different Michael donors namely, pyrazolin-5-one, 2-cyanomethylthiazolidine-2]-5-oxopentano-carbonitrile, thiobarbituric acid, cyclohexanone, and ethyl cyanoacetate affording the adducts bispyrazolo[5
Abstract: As an effort to synthesize new heterocyclic compounds, which would be expected to have a pharmacological and biological activities, we report here the reactivity of 1-(2,4-dimethoxyphenyl)-3-aryl-2-propen-1-ones (Ia&b), as Michael acceptors under different conditions, towards different Michael donors namely, pyrazolin-5-one, 2-cyanomethylthiazolidin-4-one, thiobarbituric acid, cyclohexanone, and ethyl cyanoacetate affording the adducts bispyrazolo[5,4-b]-4H-pyranes III, 5-oxopyrazolin-4-yl-propan-1-ones IV, 2-(4-oxothiazolidine-2-yl)-5-oxopentano-carbonitrile XI, 4-oxo-4H-pyranol[2,3-d]tetrahydropyrimidin-2-thiones XVI, cyclohexano[b]-4H-pyran XVII, ethyl-5-oxo-pentanoate XVIII, and 1-aroyl-2-arylcyclopropanes XIX respectively. Fusion of XI with excess ammonium acetate yielded 2-aminopyridine derivative XII and 2-aminotetrahydropyridine derivative XIII. Diazotization of XII by treatment with HNO2 at 0°C produced the diazonium chloride derivative XIV which underwent coupling reaction with phenolic compound...

Journal ArticleDOI
TL;DR: In this paper, a microwave power 0.4 KW was used to catalyze conversion of the stabilized phosphorus ylides to chromene derivatives in the presence of solid catalysts in solvent-free conditions.
Abstract: Profanation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, by phenols (1-hydroxynaphthalene, 2-hydroxynaphthalene, 4-bromophenol, 2-hydroxybenzaldehyde, and 5-bromo-2-hydroxybenzaldehyde leads to vinyltriphenylphosphonium salts, which undergo electrophilic substitution reaction with conjugate base to produce corresponding stabilized phosphorus ylides. Microwave was found to catalyze conversion of the stabilized phosphorus ylides to chromene derivatives in the presence of solid catalysts in solvent-free conditions at microwave power 0.4 KW in 3 min.

Journal ArticleDOI
TL;DR: The mechanism of asymmetric induction at the trivalent phosphorus atom was rationalized and the stereochemical properties of phosphorus acid amides were investigated in this paper, where the (R,S)-and (S,S)stereomers of aminophosphines were separated by crystallization and flash-chromatography.
Abstract: Racemic chlorophosphines react stereoselectively with chiral l-phenylethylamines or amino acid esters to give diastereomerically enriched aminophosphines 3, which were isolated as diastereomerically pure crystalline borane complexes. Oxidation, thionation, the reaction with methyl iodide provide optically active derivatives of aminophosphines. (R,S)- and (S,S)-stereomers of phosphinic acid amides were separated by crystallization and a flash-chromatography. The stereochemical properties of phosphorus acid amides were investigated. The mechanism of asymmetric induction at the trivalent phosphorus atom was rationalized.

Journal ArticleDOI
TL;DR: Sodium sulfide hydrate has been employed for an efficient reduction of a variety of azides to the primary amines in good-to-excellent yields under solvent-free system and without perturbing many active functionalities such as ether, carbonyl, sulfonyl and nitro.
Abstract: Sodium sulfide hydrate has been employed for an efficient reduction of a variety of azides to the primary amines in good-to-excellent yields under solvent-free system and without perturbing many active functionalities such as ether, carbonyl, sulfonyl, and nitro.

Journal ArticleDOI
TL;DR: New derivatives of 2-substituted pyrido[3′,2′:4,5]thieno[3,2-d]pyri-midin-4(3H) ones and 3-substrained pyridis[3',2',2'): 4,5'thienoisocyanates have been prepared by base catalyzed cyclocondensation of ethyl-3-aminothieno [3, 2-b]pyridine-2-carboxylate with aryl nit
Abstract: New derivatives of 2-substituted pyrido[3′,2′:4,5]thieno[3,2-d]pyri-midin-4(3H) ones and 3-substituted pyrido[3′,2′:4,5]thieno[3,2-d]pyri-midin-2,4(1H,3H) diones have been prepared by base catalyzed cyclocondensation of ethyl-3-aminothieno[3,2-b]pyridine-2-carboxylate with aryl nitriles and aryl- or alkyl isocyanates respectively.

Journal ArticleDOI
TL;DR: In this paper, a series of aromatic aldehydes and ketones were applied to a dipolar aprotic solvent (mainly DMF) in the presence of a base catalyst (4-methylmorpholine) and utilized microwave (mw) irradiation.
Abstract: The Willgerodt-Kindler reaction was applied to a series of aromatic aldehydes and ketones. The reactions were performed in a dipolar aprotic solvent (mainly DMF) in the presence of a base catalyst (4-methylmorpholine) and utilized microwave (mw) irradiation. The pulsed mw technique rather than the continuous irradiation was preferred because it limited side reactions and hydrogen sulfide production. While not always superior to the thermal activation of the reaction, the procedure involving repetitive short pulses of microwave irradiation was found to be faster and result in consistently cleaner products. The technique can be easily applied in a fast parallel synthesis process.

Journal ArticleDOI
TL;DR: In this paper, the reaction of β-keto-δ-carbethoxyphosphonates and phosphineoxides with active cyanoarylidenes has been studied.
Abstract: The reaction of β-keto-δ-carbethoxyphosphonates and phosphineoxides 1 with active cyanoarylidenes 2 in basic conditions provides a convenient access to the new 2-amino-6-(phosphonomethyl)-4H-pyranes 3. The reaction is found to be highly regioselective. The structure of all obtained products is confirmed by NMR ( 1 H, 31 P, 13 C), IR spectroscopy, and in some cases by mass spectrometry.

Journal ArticleDOI
TL;DR: In this paper, the nucleophilic ring opening reactions of epoxides by aliphatic alcohols and water are achieved efficiently in the presence of catalytic amounts of silica sulfuric acid with high degree of regioselectivity.
Abstract: The nucleophilic ring opening reactions of epoxides by aliphatic alcohols and water are achieved efficiently in the presence of catalytic amounts of silica sulfuric acid with high degree of regioselectivity. The catalyst is reusable and can be applied several times without any decrease in the yield of reactions.

Journal ArticleDOI
TL;DR: In this paper, the structure of N1-benzimidazolyl amidines with tris(dimethy- lamino)phosphine was confirmed by IR, 1H, 31P, and 13C NMR spectroscopy.
Abstract: The condensation of N1-benzimidazolyl amidines 1 with tris(dimethy- lamino)phosphine leads to the corresponding [1,2a]Benzimidazolo-1,3,5,2-triazaphosphorines 3 . The N2-phosphoroamidine intermediates 2′ are isolated and yielded the corresponding cyclic compounds 4 upon heating. The oxidation by sulfur of the compounds 3 gives the thiooxide derivatives 4 . The structure of these compounds is unambiguously confirmed by IR, 1H, 31P, and 13C NMR spectroscopy and by MS for some products.

Journal ArticleDOI
TL;DR: In this paper, the interaction of 1,4-phenylenediisothiocyanate with aromatic amines and o-phenyllenediamine furnished the novel bisthiourea derivatives 2a,c and 7.
Abstract: Interaction of 1,4-phenylenediisothiocyanate 1 with aromatic amines and o-phenylenediamine furnished the novel bisthiourea derivatives 2a–c and 7. Hydrazines or o-aminothiophenol reacted with 1 to produce bis-(thiosemicarbazide 4a,b or benzothiazole 9) derivatives. Bisquinazolines 12a,b and bisthienopyrimidines 13a,b were synthesized through interaction of 1 with anthranilic acids 10a,b and aminothiophenes 11a,b. Interaction of 1 with two moles of either salicylic acid or N-(4-substituted-phenyl)cyanothioformamide yielded the corresponding bis(1,3-benzoxazine 14 or imidazolidineiminothiones 16) derivatives.

Journal ArticleDOI
TL;DR: Sulfonohydrazides have achieved considerable importance as organic reagents as discussed by the authors, and they can be used in the synthesis of olefins, aldehydes, and diazo compounds.
Abstract: Sulfonohydrazides recently have achieved considerable importance as organic reagents. They can, for instance, be used in the synthesis of olefins, aldehydes, and diazo compounds, the characterizati...

Journal ArticleDOI
TL;DR: In this article, 4,5-Diaryl-2,3-dihydro-imidazoles and 2,1-b]-thiazol-3-ones were synthesized by the action of chloroacetyl chloride on compounds in pyridine.
Abstract: 4,5-Diaryl-2,3-dihydro-2-mercaptoimidazoles (2a–e) were synthesized. They reacted with chloroacetic acid in gl. acetic acid/Ac 2 O in presence of anhyd. sodium acetate afforded 5,6-diaryl-2,3-dihydro-imidazo[2,1-b]thiazol-3-ones (3a–d). Also these compounds were prepared by the action of chloroacetyl chloride on compounds (2) in pyridine. Compounds (3a–d) on condensation with aromatic aldehydes yield 2-arylmethylene-5,6-diaryl-2,3-dihydroimidazo[2,1-b]-thiazol-3-ones (4a–q). The latter compounds were prepared directly by the reaction of (2) with chloroacetic acid and the aromatic aldehydes. Compounds (3a–d) coupled with aryldiazonium salts in pyridine to give 2-arylhydrazono-5,6-diaryl-2,3-dihydroimidazo[2,1-b]thiazol-3-ones (5a–r). Also compounds (2) when reacted with 2 or 3-bromopropionic acid afford 2,3-di-hydro-5,6-diaryl-2-methylimidazo[2,1-b]thiazol-3-ones (6a–d) and 2,3-di-hydro-6,7-diaryl imidazo-[2,1-b]-1,3-thiazin-4-ones (7a–d), respectively. Compounds (3, 6, and 7) have been cleaved by aromatic...

Journal ArticleDOI
TL;DR: In this article, a means for simultaneously producing multiple alkyl methylphosphonates from methyl-phosphonic acid and corresponding alcohols was developed, which is suitable for GC/MS analysis.
Abstract: There are hundreds of nerve agents in the class of alkyl methylphosphonofluoridates covered by Schedule 1 of the CWC (Chemical Weapons Convention). Hydrolysis of these sarin-like nerve agents results in an equal number of alkyl methylphosphonic acids. These alkyl methylphosphonic acids are persistent and provide good evidence of specific agent production or use. In order to support the CWC and counterterrorism activities, it is desirable to have ready access to each of these hydrolysis products for use as qualitative standards. A means for simultaneously producing multiple alkyl methylphosphonates from methylphosphonic acid and the corresponding alcohols was developed. Derivatization of these alkyl methylphosphonic acids with trimethylsilyldiazomethane yields the corresponding methyl esters which are suitable for GC/MS analysis.

Journal ArticleDOI
TL;DR: In this paper, a mild, catalytic dehydrocoupling route to aminoboranes and borazine derivatives from either primary or secondary amine-borane adducts has been developed using late transition metal complexes as precatalysts.
Abstract: A mild, catalytic dehydrocoupling route to aminoboranes and borazine derivatives from either primary or secondary amine-borane adducts has been developed using late transition metal complexes as precatalysts. The dehydrocoupling of Me 2 NH·BH 3 was found to be catalyzed by 0.5 mol% [Rh(1,5-cod)(μ-Cl)] 2 in solution at 25°C to give [Me 2 N─BH 2 ] 2 (1) quantitatively after ca. 8 h. This new catalytic method was extended to other secondary adducts RR ′NH·BH 3 which afforded the dimeric [(1,4-C 4 H 8 )N─BH 2 ] 2 (2) and [PhCH 2 (Me)N─BH 2 ] 2 (3) or the monomeric aminoborane i Pr 2 N═BH 2 (4) under mild conditions. The catalytic dehydrocoupling of NH 3 ·BH 3 , MeNH 2 ·BH 3 , and PhNH 2 ·BH 3 at 45°C affords the borazine derivatives [RN─BH] 3 (5: R = H; 6: R = Me; 7:R = Ph). TEM analysis of the contents of the reaction solution for the [Rh(1,5-cod)(μ-Cl)] 2 catalyzed dehydrocoupling of Me 2 NH·BH 3 together with Hg poisoning experiments suggested a soluble heterogeneous catalyst involving Rh(0) nanoclusters.

Journal ArticleDOI
TL;DR: A series of O,O-diphenyl [substituted (2-selenomorpholin-4-yl-acetyl amino) alkyl phosphonates were synthesized by the reactions of selenomorpholine with O, O-,O-,Diphenymethyl 2-chloro- acetylamino (CACE)-alkyl-acetylamine (CALA) 2.
Abstract: A series of O,O-diphenyl [substituted (2-selenomorpholin-4-yl-acetyl amino)] alkyl phosphonates were synthesized by the reactions of selenomorpholine with O,O-diphenyl 2-chloro- acetylamino alkyl phosphonates The structures of all new compounds have been confirmed by 1 H NMR, 31 P NMR, IR spectroscopy, Mass spectroscopy and elemental analyses

Journal ArticleDOI
TL;DR: In this paper, the reaction of the Lawesson's reagent with aliphatic 1,2- and 1,3-diols as well as with aromatic 2,2′-dihydroxybiphenyl led to new products.
Abstract: Reaction of the Lawesson's reagent (LR) with aliphatic 1,2- and 1,3-diols as well as with aromatic 2,2′-dihydroxybiphenyl led to new products. Stable di-tert-butylammonium salts of bis-anisyldithiophosphonic acids 6 were isolated and were then converted into unique 9-, 9-, and 10-membered cyclic disulfides 7 and into S,S-dimethyl esters 8. The salts of bis-anisyldithiophosphonic acids 6 were shown to be capable of splitting the disulfide bond of Ellman's reagent.

Journal ArticleDOI
TL;DR: In this paper, it was shown that the highly reactive 1:1 intermediates produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates by alcohols leads to vinyltriphenyl-phosphonium salts, which undergo Michael addition reaction with conjugate base to produce the corresponding stabilized phosphorus ylides.
Abstract: Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, by alcohols leads to vinyltriphenylphosphonium salts, which undergo Michael addition reaction with conjugate base to produce the corresponding stabilized phosphorus ylides. Intermolecular Wittig reaction of the stabilized phosphorus ylides with ninhydrin leads to the corresponding, highly electron-poor alkenes.