Excited state solvation dynamics of 2-anilinonaphthalene

Nanosecond fluorescence spectroscopy has been used to study the interaction of 2-anilinonaphthalene with polar solvent molecules which is shown to result in stoichiometric complex formation at low polar solvent concentrations. This is followed by reorientation of the solvent cage when the concentration of polar solvent is high.     

The structure of the cations from 2– and 4-pyrimidones

An infrared spectral investigation of a number of pyrimidine and pyrimidone hexachloroantimonates is reported. Typical aromatic absorption bands found in pyrimidinium salts were absent in the pyrimidone cations. 2-And 4-Pyrimidone hexachloroantimonates, as well as their N-methyl- and N,N'-dimethyl derivatives, exhibit intense carbonyl absorption bands between 1720–1729 cm^?1 (solid state) which corroborates N-protonation of pyrimidones.     

Template-Reaktion von Bis(acetylacetonato)-dioxo-molybdän(VI) mit Benzoylhydrazin

Template Reaction of Bis(acetylacetonato)-dioxo-molybdenum(VI) with Benzoylhydrazone By reaction of bis(acetylacetonato)-dioxo-molybdenum(VI) with benzoylhydrazine benzoylhydrazido(2?)-acetylacetonebenzoylhydrazonato(2?)-oxo-molybdenum(VI) was formed beside another species. The compound was characterized by mass spectrometry and X-ray structural analysis. Crystallographic data see ?Inhaltsübersicht”?.     

Preparation and crystal structure of tetraphenylphosphonium triiodotetrabromide [PPh4][I3Br4

Tetraphenylphosphonium triiodotetrabromide [PPh4][I3Br4] is obtained by the reaction of tetraphenylphosphonium bromide with iodine monobromide. It is the first example of an iodine rich, seven-membered polybromide. [PPh4][I3Br4] crystallizes triclinic in the space group P1 with a = 10.947(1) A, b = 11.945(1) A, c = 12.896(1) A, alpha = 66.80(1) degrees, beta = 77.21(1) degrees, gamma = 85.73(1) degrees, and two formula units per unit cell. The final R indices [I > 4 sigma(I)] are R1 = 0.0362 and wR2 = 0.0944.     

Reactions of aromatic ketones with 3-mercapto-1,2-propanediol. Synthesis of cis- and trans-2-alkyl-2-aryl-(1,3-oxathiolane-5-methanols and 1,3-dioxolane-4-methanethiols)

Aromatic ketones react with 3-mercapto-1,2-propanediol ( 1 ) in refluxing benzene under the catalytic influence of a sulfonic acid and with azeotropic removal of water to yield a mixture comprised predominantly of cis- and trans-2-alkyl-2-aryl-1,3-oxathiolane-5-methanols 7, accompanied by lesser amounts of cis- and trans-2-alkyl-2-aryl-1,3-dioxolane-4-methanethiols 8 (up to 30%). It was discovered that 8 is the kinetic product and is isomerized by 4-toluenesulfonic acid in hot benzene to the thermodynamically more stable 7 . Under these conditions, ortho- and α-substituted aromatic ketones tend to produce more of 8 , which can be attributed to steric hindrance encountered by the thiol as it attacks the ketone. Ketalizations of 1-aryl-2-(1H-imidazol-1-yl)-1- as well as 1-aryl-2-(1,H-1,2,4-triazol-1-yl)-1-ethanones by 1 fail under these conditions, even after 24 hours of reflux in toluene. However, 1-(4-chlorophenyl)-3-(1H-imidazol-1-yl)-1-propanone and 1-(4-bromophenyl)-4-(1H-imidazol-1-yl)-1-butanone are ketalized by 1 as expected. Interestingly, the reaction of 2-bromo-4′-chloroace-tophenone with 1 produces 1-(4-chlorophenyl)-2,8-dioxa-6-thiabicyclo[3.2.1]octane. Characterization of all isomers and separation of some diastereomers is described. Nuclear Overhauser enhancement experiments are utilized to establish the stereochemistry of 1,3-oxathiolanes.     

Octylgermane on gold: synthesis, oxidation, and pattern formation

Chemisorbed monolayers of octylgermane (C8H17GeH3) on gold have been formed by vapor deposition in ultrahigh vacuum. The monolayer has been characterized by X-ray photoelectron and reflection absorption infrared spectroscopies (XPS and RAIRS) and scanning tunneling microscopy (STM). XPS data indicate the monolayer can be oxidized by exposure to ozone. STM images exhibit a complex pattern which can be modeled as strain-mediated spinodal decomposition.