Dimethylplatinum (II) complexes with isocyanocoumarin ligands: the crystal structure of cis-dimethylbis-(7-diethylamino-3-isocyanocoumarin)platinum(II)

Platinum complexes that contain isocyanocourmarin ligands have been prepared. [Pt₂Me₄(μ-SMe₂)₂] and [PtPh₂(SMe₂)₂] react with ligands L, (L = 7-diethylamino-3-isocyanocoumarin, Idc; 7-isocyano-4-methylcoumarin, Mic; 7-isocyano-4-trifluoromethylcoumarin, Tic; 3-chloro-4-methyl-7-isocyanocoumarin, Cmic), to give PtR₂L₂, monomers in high yield. The NMR and IR spectra of these complexes are consistent with cis stereochemistry. The UV-Vis absorption spectra of the complexes show bands assigned to ligand-centered transitions. Excitation into the absorption bands of the Idc complexes gives emission at room temperature in methylene chloride solution. The oxidative addition reaction of two of these complexes with methyl iodide has been studied. Platinum (IV) species with fac geometry have been isolated and characterized. Cis-dimethylbis-(7-diethylamino-3-isocyanocoumarin)platinum(II) was characterized by X-ray diffraction.     

Synthesis,antioxidant, antibacterial,and DFT study on a coumarin based salen-type Schiff base and its copper complex

Synthesis of new efficient compounds is becoming urgent due to the resistance of organisms to drugs. Salen derivatives have interesting therapeutic and industrial applications. A coumarin based derivative of salen, 7-hydroxy-8-((E)-((2-((E)-((7-hydroxy-5-methyl-2-oxo-3,8a-dihydro-2Hchromen-8-yl)methylene)amino)-4-methylphenyl)imino)methyl)-5-methyl-2H-chromen-2-one (L), and its copper complex, CuL, have been synthesized and characterized. Antibacterial and antioxidant activity of these compounds have been evaluated and electronic, optical and molecular properties have been calculated using density functional theory (DFT) with B3LYP. The results were correlated with the biological activity and reactivity of the compounds. Experimental and theoretical calculations indicate that the studied copper complex has the potential to function as a drug.     

X-ray and nmr spectroscopic study of substituted 2-alkylidene-7-diethylaminobenzopyrans

The structures of 4-methyl-7-diethylamino-2-(acetylcarbethoxymethylene)- and 4-methyl-7-diethylamino-2-(cyanocarbethoxymethylene) benzopyran were investigated by X-ray structural analysis. It was shown that the crystalline compounds have strong intramolecular charge separation and a single conformation in which the largely acceptor substituent, exomethylene, is near atom 3-H of the benzopyran fragment. Based on low temperature NMR spectra, it was concluded that an analogous conformation predominates in solution.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1028–1033, August, 1988.     

Two-photon microstructure-polymerization initiated by a coumarin derivative/iodonium salt system

Two-photon polymerization initiated by a bimolecular initiating system composed of 7-diethylamino-3-(2^′-benzimidazolyl)coumarin and diphenyliodonium hexafluorophosphate was investigated. The photosensitizer has been proven to possess large two-photon absorption cross-section for 800 nm femtosecond laser. The sensitizer/coinitiator system has high photosensitivity for the photopolymerization of methyl methacrylate. This photopolymer system has been demonstrated for fabricating three-dimensional microstructure.     

Synthesis and spectral-luminescence properties of azomethines in the coumarin series

Nitration of 7-diethylamino-4-methylcoumarin and reduction of the resulting 3-nitro derivative gave 7-diethylamino-3-amino-4-methylcoumarin. A series of azomethines have been synthesized based on this material. The spectral-luminescence properties of the products have been investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 321–323, March, 1990.     

Synthesis and spectral-luminescence properties of 7-diethylamino-4-(2-arylethenyl)coumarins

A number of 7-diethylamino-4-(2-arylethenyl)coumarins were obtained by condensation of 7-diethylamino-4-methylcoumarin with aromatic aldehydes, while only a product of addition to the carbon—nitrogen double bond is formed with benzalaniline. The spectral-luminescence properties of the compounds obtained were investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 319–322, March, 1991.     

Unidirectional switching between two flavylium reaction networks by the action of alternate stimuli of acid and base

The introduction of an ester group in the flavylium core allowed the reversible conversion between two different flavylium compounds each one exhibiting its own reaction network. An unidirectional switching cycle between 7-diethylamino-2-(4-(methoxycarbonyl)phenyl)-1-benzopyrylium and 2-(4-carboxyphenyl)-7-diethylamino-1-benzopyrylium was achieved by means of alternate acid and base stimuli. Addition of base to a methanolic solution of the ester derivative gives rise to the trans-chalcone of the parent carboxylic acid, which upon acidification of the solution forms the respective flavylium cation. This species esterifies under very acidic conditions to restore the original methyl ester derivative. The chemical reaction networks of both compounds were fully characterized from their thermodynamic and kinetic aspects, by a series of pH jumps followed by UV-vis absorption and emission spectroscopy, stopped flow and (1)H NMR. The crystal structure of the trans-chalcone of the ester derivative was unveiled showing a supramolecular structure involving hydrogen bonding.     

Synthesis and cyclization reactions of 2-amino-3-[(methoxy-carbonyl)methylsulfonyl]pyrroles and thiophene

The title aminopyrroles and thiophene have been prepared by condensation of methyl (cyanomethyl-sulfonyl)acetate with various α-amino ketones or 2-mercaptoacetaldehyde, respectively. Subsequent cyclization of these compounds by reaction between the amine and activated methylene has led to various ester-substituted thiazine- and thiadiazine-based bicyclic derivatives. In addition, cyclization of the title compounds by intramolecular coupling of the amine and ester has led to the analogous bicyclic thiazin-3(2H)-ones. Attempted hydrolysis of the ester-substituted bicyclics to the corresponding carboxylic acids was unsuccessful.     

Reaction of citral with acetone cyanohydrin and diethylamine,and thermolysis of the resulting aminonitrile

The reactions of citral with acetone cyanohydrin and secondary amines (diethylamine, piperidine, morpholine, and N-methylaniline) to give 2-substituted amino-4, 8-dimethyl-3,7-nonadienoic acid nitriles have been examined. Possible path-ways for these reactions are discussed. The thermolysis of 2-diethylamino-4,8-dimethyl-3, 7-nonadienoic acid nitrile has been examined in solution, to give irreversibly 3-cyano-1-diethylamino-3,7-dimethyl-1,6-octadiene, this reaction proceeding faster in polar than in nonpolar solvents.The synthetic citral used contained, according to GLC, 65% of the E- and 35% of the Zisomer.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2033–2038, September, 1989.     

Studies on pyrrolidones. Synthesis and N-alkylation of β-enaminoesters derived from pyroglutamic acid

The condensation of iminoether 7 , derived from pyroglutamic acid (4) , with active methylene reagents such as Meldrum's acid or methyl cyanoacetate, lead to β-enaminoesters 2 . Solid-liquid phase transfer N-alkylation of these compounds is described.     

Free radical ring‐opening polymerization of cyclic allylic sulfides: Liquid monomers with low polymerization volume shrinkage

The free radical polymerization of four methylated cyclic allylic sulfides was examined with reference to their polymerization volume shrinkage and the effect of ring size on reactivity. The compounds examined were 2‐methyl‐5‐methylene‐1,3‐dithiane ( 5 ) (solid), 2‐methyl‐6‐methylene‐1,4‐dithiepane ( 6 ) (liquid), 6‐methyl‐3‐methylene‐1,5‐dithiacyclooctane ( 7 ) (liquid), and 6,8‐dimethyl‐3‐methylene‐1,5‐dithiacyclooctane ( 8 ) (liquid). The monomers were stable materials not requiring any special handling or storage conditions. They were polymerized in bulk using thermal azobisisobutyronitrile (AIBN, VAZO88) and photochemical initiators (Ciba DAROCUR 1173) and in benzene solutions (AIBN, 70 °C). The six‐membered ring monomer 5 was unreactive whereas seven‐membered ring monomer 6 polymerized to high conversion in bulk. In addition, 6 did not polymerize in benzene solution at 70 °C at [ 6 ] = 1.25M. Eight‐membered ring monomers 7 and 8 polymerized in bulk to complete conversion with thermal and photochemical initiators to give lightly crosslinked materials. Near complete conversion to soluble polymers could be obtained in solution polymerizations in benzene. Soluble polymers were also obtained in photochemical initiated bulk polymerizations by lowering initiator concentrations or length of irradiation. The methyl substituent had no effect on which allylic carbon–sulfur bond fragmented in the ring‐opening step. The polymerization volume shrinkages of monomers 7 and 8 were 1.5 and 2.4% respectively and together with monomer 4 (1.5–2.0% shrinkage) are the best available liquid free radical ring‐opening monomers that can be polymerized in bulk at room temperature. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 202–215, 2001     

Syntheses,Characterization, and Antibacterial Activities of Four New Schiff Base Compounds Derived from 1‐Phenyl‐3‐methyl‐4‐benzoyl‐2‐pyrazolin‐5‐one

Four new Schiff bases were designed and synthesized. 5‐Methyl‐4‐(4‐aminophenylamino‐phenyl‐methylene)‐2‐phenyl‐2,4‐dihydro‐pyrazol‐3‐one (compound 1 ) and 5‐methyl‐4‐(2‐aminophenylamino‐phenyl‐methylene)‐2‐phenyl‐2,4‐dihydro‐pyrazol‐3‐one (compound 2 ) were synthesized by interaction of 1‐phenyl‐3‐methyl‐4‐benzoyl‐2‐pyrazolin‐5‐one (PMBP) with o‐ and p‐phenylenediamine, respectively; 4,4′‐(1,2‐phenylenebis(azanediyl)bis(phenylmethanylylidene))bis(3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐one) (compound 3 ) and 5‐methyl‐4‐(phenyl(2‐((3‐phenylallylidene)amino)phenylamino)methylene)‐2‐phenyl‐2,4‐dihydro‐pyrazol‐3‐one (compound 4 ) were synthesized by interaction of compound 2 with PMBP and cinnamaldehyde in an ethanolic medium, respectively. The molecular structures of the title compounds were first characterized by single‐crystal X‐ray diffraction, mass spectrometry, and elemental analysis. The title compounds were tested for antibacterial activity (Escherichia coli, Staphylococcus aureus, and Bacillus subtilis) by disk diffusion method.     

PPh3‐catalyzed knoevenagel condensation: A facile synthesis of 5‐(1H‐indol‐3‐yl)Meth‐ ylene)‐2, 2‐Dimethyl‐1, 3‐Dioxane‐4, 6‐dione,and their N‐alkyl derivatives by using peg‐600 as the reaction medium

Triphenylphosphine (TPP) has been utilized as a novel and efficient catalyst for the Knoevenagel condensation of indole‐3‐carboxaldehydes 1(a–e) , 1‐methyl‐1H‐indole‐3‐carboxaldehydes 4(a–e) , and 1‐ethyl‐1H‐indole‐3‐carboxaldehydes 6(a–e) with the active methylene compound, that is, meldrum's acid ( 2 ), to afford substituted derivatives 5‐((1H‐indol‐3‐yl) methylene)‐2,2‐dimethyl‐1,3‐dioxane‐4,6‐dione 3(a–e) , 2,2‐dimethyl‐5‐((1‐methyl‐1H‐indol‐3‐yl)methylene)‐1,3‐dioxane‐4,6‐dione 5(a–e) , and 2,2‐dimethyl‐5‐((1‐ethyl‐1H‐indol‐3‐yl)methylene)‐1,3‐dioxane‐4,6‐dione 7(a–e) , respectively, in ethanol medium at RT just within 1 h in excellent yields. The products 3(a–e) were reacted independently with alkylating agents, that is, DMS and DES in the presence of PEG‐600 as an efficient and green solvent, to afford the corresponding N‐substituted methyl and ethyl derivatives 5(a–e) and 7(a–e) , respectively. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:41–48, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20750     

Sydnones as Masked Hydrazines for the Synthesis of 4‐Arylazo‐1,2‐dihydro‐pyrazol‐3‐one Derivatives

A simple and convenient one‐pot synthesis of 4‐(4‐chlorophenylazo)‐5‐methyl‐2‐aryl‐1,2‐dihydro‐pyrazol‐3‐ones (4a–j) has been carried out from 3‐arylsydnones (3a–j) by reaction with 2‐(4‐chlorophenyl)‐hydrazono‐3‐oxo‐butyric acid ethyl ester (2b). The 3‐arylsydnones are used as masked hydrazines in this reaction. Similarly, the 4‐arylazo‐2‐(7‐hydroxy‐4‐methyl‐2‐oxo‐2H‐chromen‐8‐ylmethyl)‐5‐methyl‐1,2‐dihydro‐pyrazol‐3‐ones (7a–j) were synthesized from 3‐[(7‐acetoxy‐4‐methyl‐8‐methylene)coumaryl]sydnone (5). All the newly synthesized compounds exhibited antimicrobial activity greater than the reference drugs used.     

Retention behaviour of 1,n-halo(alkylthio)alkanes in HPLC

The RPLC retention of 1,n-halo(alkylthio)alkanes on an ODS phase with methanol/water (95%/5%) has been investigated. Replacement of a methyl group in a dialkyl sulphide R-S-R by a halogen atom X, to yield the title compounds X-(CH₂)_n-S-R, generally results in a retention decrease. This retention loss results either from the halogen atom proper, or from its immediate vicinity, or from a reduced retention contribution of the alkyl units. The methylene groups (n) between halogen and sulphur produce somewhat greater retention than the methylene groups in the alkyl groups R.     

Condensation of aldehydes and ketones

The Mannich reaction with methylene- and benzylidenediacetophenones has given: 1,3-dibenzoyl-4-piperidinobutane, 1,3-dibenzoyl-4-morpholinobutane, 1,3-dibenzoyl-4-diethylamino-2-phenylbutane, 1,3-dibenzoyl-2-phenyl-4-piperidinobutane, 1,3-dibenzoyl-4-diethylaminobutane, and 1,3-dibenzoyl-4-dimethylamino-2-phenylbutane. From the latter two compounds, 3-diethylaminomethyl-2,6-diphenylpyridine and 3-dimethylaminomethyl-2,4,6-triphenylpyridine have been obtained.For part XVII, see [7].     

A NMR Study of Magnetic Nonequivalence of Methylene Protons in Some 1,1,2-Trisubstituted Ethanes of the Type XCH2 CHXY

Magnetic nonequivalence of methylene protons in some 1,1,2-trisubstituted ethanes of the type XCH₂ CHXY was studied in the medium of various solvents over the temperature range of 0–95°C. Asymmetry effect and rotamer populations have been considered to be two major contributions to magnetic nonequivalence of methylene protons in the title compounds. A graphic method has been proposed to determine the asymmetry effect for methyl 2,3-dibromopropionate, ethyl 2,3-dibromopropionate, methyl 2,3-dichloropropionate, and (1,2-dibromoethyl) benzene in various solvents.     

1 ,3 ,2-Oxazaphospholidine Derivatives(I)——The Synthessa of 2 - Diethylamino- 3-arylsulfonyl- 1,3,2-Oxazaphospholidine and Its 2-thiono Deiativea and Their Properties

A series of new 2-diethylamino-3-substituted phenylsulfonyl-1,3,2-oxazaphospholidine derivatives (Ⅰ) has been synthesized by the reaction of tris(diethylamino) phosphine with N-(β-hydroxyethyl) substitutedphenylsulfonamides. When was refluxed with sulfur in benzene, the 2-thiono derivatives (Ⅱ) was obtained conveniently.(Ⅰ) was easily oxidized in air and the diethylamino group could be substituted by phenoxy or other amino group giving the corresponding derivatives. Their H NMR and MS spectra have been discussed. Some of compounds (Ⅱ) have herbicidal activities.     

l, 9-Substituted fluorenes

The synthesis of 2-methyl (phenyl)-2, 3H-pyridazino-[4, 5, 6-m- l] fluorene-3-methylthionium methylsulfates and of derivatives with substituents in the fluorene ring, is described. Reaction of the latter with heterocyclic hydrazones, and also with compounds containing an active methylene or methyl group, gives cyanine dyes. The electronic spectra of the dyes are measured.For Part III see [3].     

Transformations of the initial product of the reaction of citral with acetone cyanohydrin

Conclusions Citral reacts with acetone cyanohydrin and diethylamine to form 2-diethylamino-4,8-dimethyl-3,7-nonadienenitrile, which is converted on fractional distillation or standing to a mixture of 1-diethylamino-3,7-dimethyl-1,3,6-octatriene, 2-diethylamino-4,8-dimethylamino-2, 7-nonadienenitrile, and 1-diethylamino-3,7-dimethyl-3-cyano-1,6-octadiene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 615–619, March, 1980.