Bulk elastic energy of bismuth crystal twins and the surface energy of the twin-matrix interface in a magnetic field

Partial suppression of twinning in bismuth crystals in a static magnetic field is found not to be accompanied by a change in the bulk elastic energy stored in wedge twins. Application of a magnetic field decreases the surface energy of the twin-matrix interface.     

Characteristics of polyether urethanes with mixed soft segments,prepared by two- and three-step procedures

A three-step procedure for preparing polyurethanes with mixed polyether segments was suggested. It involves preparation of the “inverse” prepolymer by the reaction of one of oligodiisocyanates with 1,4-butanediol taken in a double excess, followed by the reaction with the other oligodiisocyanate. Polyurethanes with alternating poly(tetramethylene oxide) and poly(propylene oxide) soft segments were prepared by this procedure. Such materials surpass polyurethanes prepared from a mixture of oligodiisocyanates in the strength and softening point of the hard phase. In contrast to poly(tetramethylene oxide) urethane, elastomers with mixed polyether segments do not crystallize.     

Synthesis of 2,3‐dihydro‐1,3‐thiazin‐4(1H)‐ ones and their remarkably facile recyclization to 2,3‐dihydropyrimidin‐4(1H)‐ones

Functionalized 2,3‐dihydro‐1,3‐thiazin‐4(1H)‐one derivatives have been synthesized by cyclocondensation of 3‐alkyl(aryl)amino‐2‐cyano‐3‐mercaptoacrylamides with aldehydes and ketones under acidic catalysis. 6‐Alkyl(aryl)amino‐5‐cyano‐2,3‐dihy‐ dro‐1,3‐thiazin‐4(1H)‐ones, when treated with a dilute solution of potassium hydroxide, are converted into the potassium salts of isomeric compounds, 1‐alkyl‐ (aryl)‐5‐cyano‐6‐mercapto‐2,3‐dihydropyrimidin‐ 4(1H)‐ones. Alkylation of the latter with dimethyl sulfate in situ furnishes 1‐alkyl(aryl)‐6‐alkylthio‐5‐ cyano‐2,3‐dihydropyrimidin‐4(1H)‐ones, whereas boiling them in ethanol with an excess of hydrochloric acid leads to starting 2,3‐dihydro‐1,3‐thiazin‐4(1H)‐ones. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:426–436, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20129     

C‐acylation of electron‐rich heterocyclic compounds with Kirsanov isocyanate

Pyrroles, indoles, indolizines, and 2‐methylfuran are vigorously C‐acylated with isocyanatophosphoryl dichloride. The resulting heteroaryl‐substituted isocyanatophosphoryl dichlorides provide a convenient access to a variety of products.© 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 343–348, 1999     

New approach to CF3-containing polysubstituted anilines: reaction of β-trifluoroacetylvinyl ethers with enamines

The reaction of β-trifluoroacetylvinyl ethers with ‘push-pull’ enamines having a methyl group at the α-position was investigated. As a result, a set of CF₃-containing dialkyl anilines and their covalent hydrates were obtained. A possible reaction mechanism and the stability of the covalent hydrates obtained are discussed.     

C-Phosphorylation of Formamidines

C-Phosphorylation of formamidines by trivalent phosphorus halides was researched. Direction of the phosphorylation depends on nature of substituents at the amidine nitrogens. C-Phosphorylated products was shown to be of valuable possibilities to construct phosphoruscontaining heterocycles     

5‐phosphorylated 1,2‐disubstituted imidazoles

1,2‐Disubstituted imidazoles react with phosphorus(III) halides in pyridine regioselectively at position 5. The reaction proceeds the more readily, the higher the electron‐donating ability of the 2‐substituent in the starting imidazole. Hitherto unknown dihalo(imidazol‐5‐yl)phosphines have been obtained, and their properties have been studied. Also synthetic methods for the preparation of various monohalo(organyl)(imidazolyl)phosphines have been developed. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:289–308, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20550