Photochemistry of N-acylimino-isoquinolinium and -quinolinium betaines

The photochemical behavior of N-acyliminoisoquinolinium and -quinolinium betaines has been investigated. In contrast to pyridinium betaines, the principal course of reaction is the 1,2-migration of N-acylamino groups. Substituent effects as well as solvent effects are observed. The results are rationalized in terms of diaziridine intermediates.     

On the miscibility gap in liquid bismuth-bismuth tribromide system

We have determined the location of the miscibility gap in liquid Bi-BiBr₃ system in the concentration-temperature, x?T, plane from the measurement of the electrical conductivity. The measurements have been done in the concentration range between 30.5 and 92.5 mol.% Bi and in the temperature range between 300 and 600°C. It is found that the temperature dependence of the conductivity of the mixture changes near the retrograde solubility region.     

Mono-N-amino salt of benzodiazines and naphthyridines

The mono-N-amino salts of 3-phenylcinnoline, phthalazine, 1-phenylphthalazine, 4-phenylquinazoline, 2-phenylquinoxaline, 1,5- and 1,8-naphthyridines are in high yields prepared by direct N-amination of the parent heterocycles with O-mesitylenesulfonylhydroxylamine. With the one expection of 3-phenylcinnoline, the site of N-amination was determined by mass and nmr spectral techniques. The results indicate that the N-amination occurs preferentially at the least sterically hindered nitrogen atom.     

Acid-catalyzed cyclizations of n-vinyl-α-sulfinylacetamides A novel synthetic approach to erythrinane

Under the Pummerer reaction conditions, N-(1-cyclohexenyl)-N-methyl-α-(methylsulfinyl)acetamide ($\text{7a}$) cyclized in a 5-endo trigonal fashion through the intermediary cation ($\text{8}$) to give the tetrahydro-4H-oxindole ($\text{10}$). The reaction was successively applied to a novel synthesis of erythrinane skeleton.     

Outside dislocations generated from phosphorus implanted silicon layers

The growth, movement and nature of outside dislocation, which propagate from heavily phosphorus (>10¹⁵ ions/cm²) implanted (111), (100), and (110) silicon layers into unimplanted outside regions by a compressive strain induced during 1100° C wet O₂ annealing, are investigated using transmission electron microscopy and x-ray diffraction topography. Outside dislocations are formed, mainly on (111) planes., by the glide motion of dislocation networks formed in implanted layers during early annealing. This results in dislocations extending into the unimplanted areas to different degrees, in the order of, from the largest to smallest, (111), (110), and (100) wafers. In (110) wafers, the [001] oriented dislocations in the implanted regions rise to the surface at the implant and unimplant boundary. On the other hand, the [110] dislocations penetrate into the unimplanted region. Two sets of orthogonal 〈110〉 oriented dislocations generated in (100) implanted wafers behave in the same manner as the [001] dislocations in (110) wafers. Some sources of the compressive strain related to the generation of these dislocations are discussed.     

Spontaneous racemization and epimerization behavior in solution of chiral nitroxides

[reaction: see text] Enantiomerically enriched samples of chiral cyclic nitroxides with a 4-hydroxyphenyl group on the stereogenic center bearing the NO radical group undergo unprecedented spontaneous racemization and/or epimerization in aprotic solvents, which can be well accounted for by the multistep equilibrations involving planar quinoid intermediates.