A Convenient and Environmentally Benign Method of Reducing Aryl Ketones or Aldehydes by Zinc Powder in an Aqueous Alkaline Solution

A convenient and environmentally benign method for reducing the carbonyl group in hydroxy- and amino- 9,10-anthracenediones, ortho （or para） acyl phenols and acyl anilines to a methylene group by zinc powder in an aqueous sodium hydroxide solution was reported. Based on theoretical calculations using the density functional theory （DFT）, the mechanism of these reduction reactions was postulated. This mechanism can be applied to help predicting the reduced products of aryl ketones （or aldehydes） in an alkaline solution.     

N-磺化手性β-氨基醇修饰的钛试剂催化下的酮的不对称炔基化反应研究

The easily prepared and recoverable chiral N-sulfonylated fl-amino alcohol 2 in combination with Ti（OPr-i）4 was found to be an effective chiral catalyst for the enantioselective addition of alkynylzinc to ketones, which gave the useful products, i.e. chiral tertiary propargyl alcohols, with the ee up to 92%.     

Potentiometric and viscometric study of the alkalization of latex dispersions of ethyl acrylate — methacrylic acid copolymers in the presence of salt

The behavior of latices of ethyl acrylate — methacrylic acid copolymers during alkalization was investigated using potentiometric titration and viscometry. In the presence of NaCl in dispersion medium pH and viscosity were lower compared to salt-free dispersions. Due to strong electrostatic interactions at low salt concentration the apparent dissociation constant of the carboxylic groups is small and the polymer segments bearing these groups are in extended conformations. The screening effect at higher salt concentration increases the apparent dissociation constant and decreases the extension of the polymer segments. The pH and viscosity of latex dispersions alkalized in the presence of salt are thus smaller.     

甾酮类化合物的碱催化自氧化反应的研究

酮类化合物的碱催化自氧化反应受底物的结构和反应条件的影响较大。不同的底物或不同的反应条件,可得不同类型的产物。在油菜甾醇内酯 B 环的合成中,曾探索了用该反应来合成内酯环。本文报道一些与三元环共     

The solubility limit of a solid solutions for the systems of long-chain symmetrical ketones in ann-alkane matrix

The systems of long-chain symmetrical ketones inn-alkane matrices form solid solutions for a low concentration range of the ketone, when the number of carbon atoms n in a ketone molecule Kn is equal to or lower than that in an-alkane molecule. The Kn examined were K25 to K39. The purity of all the samples used was very high. The solubility limit of these solid solutions was determined with DSC measurements. Above the solubility limit (the critical concentration) the systems changed to eutectic mixtures. The relationships for the solubility limit were derived, taking into consideration the lateral two-dimensional and the longitudinal positioning along the chain axes and the correlating energies. The multiplicity of the longitudinal positioning led to a remarkable increase in the solubility limit of the systems of Kn/Cn (n>n). The present result points to the importance of the entropy of mixing and also for the stability of long-chain crystals.     

Conformational Mobility of 4,4′-Bisdimethyl-Aminobenzophenone in the Excited State

Quantum-chemical calculations on various conformational states of the molecule of Michler’s ketone have been carried out by semi-empirical and non-empirical methods (HyperChem 7.0 suite of programs and Gaussian 98). The influence of solvation on the relative levels of different orbital types and on the spin states of the molecule has been examined. The possibility of the TICT process occurring in polar media, which may have an important effect on the spectral characteristics of Michler’s ketone, has been investigated.__________Translated from Teoreticheskaya i Eksperimental’naya Khimiya, Vol. 41, No. 3, pp. 185–189, May–June, 2005.     

对氰基苯甲酸乙酯的合成研究

以对氨基苯甲酸乙酯为原料，经重氮化反应及Sandmeyer的氰化反应制得对氰基苯甲酸乙酯，对重氮盐的制备及氰化过程进行了研究，简化了操作，提高了产物收率。     

C-Stannylmethylierte N-Acetyl- und N-Formyl-aminomalonsäure-Derivate

C-Stannylmethylated N-Acetyl- and N-Formyl-aminomalonic Acid Derivatives Tin compounds of the type Me₃SnCH₂C(NHCOR) · (COOEt)₂ ( 1 : R = CH₃; 2 : R = H) are synthesized by reaction of acylaminomalonates with iodomethyl trimethylstannane. The halogenation of 1 and 2 yields the halostannylsubstituted compounds Me_3?nX_nSnCH₂C(NHCOR)(COOEt)₂ 3–6 (R = Me, H; n = 1, 2; X = Cl, Br). The decarbethoxylation (KRAPCHO reaction) of 1 and 2 gives ethyl 3 -(trimethylstannyl)-N-acyl alaninates ( 7 and 8 ). With one equivalent KOH 1 and 2 are transformed into the monoethyl malonates of the type Me₃SnCH₂C(NHCOR)(COOH)(COOEt) ( 9 : R = CH₃), which convert simultaneously under decarboxylation into 7 and 8 and by cyclisation under elimination of methane into the 1,2-oxastannolane derivatives 10 and 11 . IR, NMR data and the determination of the crystal structure reveal for MeBr₂SnCH₂C(NHCOCH₃)(COOEt)₂ ( 5 ) hexacoordinated tin by intramolecular coordination of the amide-CO and one of the ester-CO groups.     

The synthesis of 4-(2,6,10-trimethyl-1,3,5,9-undecatetraenyl)benzoic acid based on alkoxy alkene-acetal condensation

4-(2,6,10-Trimethyl-1,3,5,9-undecatetraenyl)benzoic acid (1) was synthesized starting from ethyl 4-formylbenzoate (2) and linalool. The key intermediate, ethyl 4-(2-methyl-3-oxo-1-propenyl)benzoate (5), was obtained by the addition of diethyl acetal (3), prepared from2, to ethyl 1-propenyl ether (EPE) followed by the hydrolysis of the resulting adduct.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 914–915, May, 1993.     

Quantum calculation of the intrinsic torsional barrier of C-C and C-O bonds

PCILO and ab initio calculations have been performed to investigate the energies associated to rotation about the central bond in n-butane and methyl ethyl ether. Quantum mechanical energies have been fit to a classical intramolecular force field, containing torsional and nonbonded (Lennard-Jones 6–12 plus Coulomb) contributions, with a standard deviation comprised between 0.03 and 0.09 kcal mol^–1. Two conditions have proved indispensable to reach such level of accuracy: (a) the use of a torsional potential with threefold periodicity, which corrects for the part of the rotation barrier not covered by van der Waals repulsions and may be interpreted as bond-bond repulsion; (b) the introduction in the force field for ethers of terms accounting for orbital interaction effects of different nature than the normal molecular mechanics nonbonded interactions; these terms are represented either by low order rotational potential functions or preferably by interactions of atoms simulating lone-pair orbitals and bonded to oxygen in such a way as to render it sp ³-hybridized. According to ab initio, the height of the threefold torsional potential about C-C and C-O bonds is comparable and is of the order of 3 kcal mol^–1. According to PCILO, it is larger for C-C (ca. 1.5 kcal mol^–1) than for C-O (ca. 0.5 kcal mol^–1).