(Z)-3-chloro-3-(2-naphthyl)prop-2-enal in the synthesis of naphthyl-substituted thiophene and quinolines

2-(2-Naphthyl)thiophene was synthesized by condensation of 3-chloro-3-(2-naphthyl)prop-2-enal with sulfanylacetic acid. A modified procedure was proposed for the synthesis of 2-(2-naphthyl)-and 2-(2-naphthyl)-6-nitroquinolines from 3-chloro-3-(2-naphthyl)prop-2-enal.     

Synthesis of 2-(2-Naphthyl)quinolines from Z-3-(2-Naphthyl)-3-chloro-2-propenal

By reaction of Z-3-(2-naphthyl)-3-chloro-2-propenal and aromatic amines 1-(2-naphthyl)-3-iminoaryl-1-propenylarylamines were prepared which at heating in the glacial acetic acid afforded the corresponding 2-(2-naphthyl)quinolines.     

Synthesis and Properties of Copper,Mercury, and Silver (2-Naphthyl)acetylenides

(Z)-2-Naphthylacetylene was synthesized by the reaction of (Z)-3-(2-naphthyl)-3-chloropropenal (prepared from 2-acetylnaphthalene) with aqueous NaOH in dioxane. The reactions of 2-naphthylacetylene with CuCl, [Ag(NH₃)₂]NO₃, and K₂[HgI₄] gave copper, silver, and mercury 2-naphthylacetylenides, respectively. Silver naphthylacetylenide reacts with iodine to give the iodoethynyl derivative, which readily takes up bromine across the triple bond.     

Improving the structure of the quasi-line fluorescence spectrum of 1,12-benzperylene with ultrafast freezing

We propose a procedure for improving the structure of quasi-line luminescence spectra of organic compounds at low temperatures. The procedure essentially involves spraying the test solution directly into liquid nitrogen, leading to ultrafast crystallization, and then collecting the polycrystalline mass. Such a procedure can be used for spectrofluorimetric analysis of the polycyclic aromatic hydrocarbon content in natural and anthropogenic media.     

Uncommon Heterocyclization into a Pyrazole System of <Emphasis Type="Italic">Z</Emphasis>-3-(2-Naphthyl)-3-chloro-2-propenal Semicarbazone and Thiosemicarbazone

By reaction of Z-3-(2-naphthyl)-3-chloro-2-propenal with semicarbazide hydrochloride and thiosemicarbazide the corresponding semicarbazone and thiosemicarbazone were obtained that underwent a heterocyclization into a pyrazole system with elimination of amide moieties and with migration of the naphthyl fragment into the position 4 of the pyrazole ring. The alkylation of 4-(2-naphthyl)pyrazole synthesized with 2-nitropentachloro-1,3-butadiene afforded 1,1-bis[4-(2-naphthyl)-pyrazol-1-yl]-2-nitrotrichloro-1,3-butadiene.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 753–755.Original Russian Text Copyright © 2005 by Vashkevich, Potkin, Kozlov.     

Migration-Accelerated Quenching of Triplet Excitations of Organic Molecules in Toluene at 77 K

The influence of the organic molecule (naphthalene, acenaphthene, and benzophenone) concentration in toluene at 77 K on the phosphorescence parameters of degassed and non-degassed solutions is studied for organic molecule concentrations ranging from 0.025 to 0.8 M. The migration-accelerated quenching of triplet excitations of naphthalene and acenaphthene by oxygen molecules is established. A conclusion is drawn that this quenching mechanism can be one of the main reasons for the influence of the concentration on the phosphorescence parameters of impurity centers in non-degassed solid solutions of organic compounds at 77 K.     

Plane-parallel plates as laser reflections

The problem of the reflectivity of complex reflecting systems in laser devices is investigated. Specific attention is given to plane-parallel plates acting as laser reflectors.The authors are grateful to B. A. Sotskii, A. M. Goncharenko, and F. I. Fedorov for their useful comments.     

A laser with a passive Q switch

A phototropic KS-19 glass switch is considered. It is shown that interference effects cause reflections from the ends of the rod and the faces ot the switch to reduce the pulse energy. The effect is suppressed by bringing the shutter into optical contact with the rod. The advantages are discussed.