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Cyclization of 2-(3-oxoalk-1-ynyl)-3-amino-1,4-naphthoquinones under the action of hydrogen bromide followed by Sonogashira cross-coupling of the thus formed 4-bromo substituted azaanthraquinone with terminal acetylenes represent the one-pot synthesis of 4-alk-1-ynyl-1-aza-9,10-anthraquinones.

Sterically hindered 1,3-diketones react selectively with propargyl and allyl bromides under conditions of phase transfer catalysis to giveC-alkylated products, whereas reactions with butyl and benzyl chlorides yield mixtures ofC- andO-isomers. An increase in the size of the substituents present in the initial 1,3-diketone hampers introduction of the second propargyl group. The propargyl-substituted 1,3-diketones undergo cyclization under the alkylation conditions to give substituted furans.

2-Alkynyl-l-amino-9,10-anthraquinones react with HNO2 in a mixture of dilute HCl and dioxane at 20 °C to give I , 1-dichloroalkyl- IH-3-naphto[2,3-g]indazole-6,1 1 -diones. This reaction differs from the known cylization ofortho-alkynylbenzenediazonium salts involving the formation of a pyridazine ring (the Richter synthesis of 4-hydroxy- and 4-halocinnolines).

Four pathways of synthesis of 1-(2-pyridyl)heptacosa-12,14-diyne, using 10-bromodecan-1-ol and acetylene or tetradec-1-yne and 2-methylbut-3-yn-2-ol along with α-picoline as initial compounds, were studied and compared. It was shown that direct introduction of a completely formed unsaturated hydrocarbon chain into an α-picoline molecule by alkylation of its lithium derivative is the most appropriate method for preparation of long-chain 2-alkadiynylpyridines.

Molecular beam mass spectrometry was used to study the structure of a premixed H 2 -O 2 -Ar(0.26-0.13-0.61) flame without additives, and with additive (0.2–0.4%) of trimethyl phosphate (TMP) stabilized on a flat-flame burner at 47–80 torr. The behavior of TMP in the flame and the influence of the additve on the flame structure have been studied. Mass spectra of samples taken from the flames and intensity profiles of peaks 1 (H), 16 (O), 17 (OH), 18 (H 2 O), 28 (CO), 32 (O 2 ), 40 (Ar), 44 (CO 2 ), 47 (PO), 63 (PO 2 ), and 64 (HPO 2 ). AMU, and of peaks 80, 95, 96, 98, 110, 111, 112, 126 and 140 (TMP) AMU have been measured as a function of the distance from the burner surface to the sampling probe, using a quadrupole mass spectrometer and electron impact ionization at 12.9–21 eV with a spread of electron energy±0.25 eV. Intensity profiles of masses 95, 96, 126, 111, and 112 pass through a maxima, and those of masses 80, 109, and 110 pass through two maxima. Such behavior of intensity profiles shows that the species responsible for these masses are intermediates or fragmentary ions of intermediates. Dimethyl phosphate, dimethyl phosphite, monomethyl phosphate, and monomethyl phosphite were proposed to be the intermediates. The profile of the temperature in the flame has been determined by using a Pt-PtRh (10%) thermocouple covered by Ceramabond 569. The promotion of the H 2 O 2 Ar flame by the TMP additive has been observed. The possible chemical mechanism of TMP destruction is presented.

Acyl derivatives of 2-aminopyridine, 2-aminopyrimidine, 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl, and 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl were obtained from long-chain diacetylenic acyl chlorides and the corresponding heterocyclic compounds. Spreading isotherms of monolayers on a water surface show that lengthening of the hydrocarbon chain and replacement of the pyridyl groups in these compounds by the more hydrophilic pyrimidyl groups render the films more condensed. Long-chain acyl derivatives of nitroxyl radicals form monolayers possesing a low collapse pressure. ESR spectra of Langmuir-Blodgett films of these radicals before and after photopolymerization were recorded.

Cleavage of long-chain 2-methyl-3,5-alkadiyne-2-ols in anhydrous benzene in the presence of KOH (Favorsky retroreaction) is accompanied by migration of the triple bonds and it affords 2,4-alkadiynes. Proton-donor additives (alcohol or water) completely suppress the isomerization process and enable preparation of terminal acetylenes in high yields.

A diversity of polyfluorinated ortho-alkynylanilines (IV), versatile building blocks for diverse polyfluorobenzo-fused azaheterocycles, is prepared by means of Sonogashira coupling reaction of polyfluorinated ortho-iodoanilines (II) with terminal alkynes (III).

Addition of chemically active compounds to flame, which are able to change the flame velocity, the flame propagation limits and the other macrokinetic parameters, seems to be the most effective way to control combustion. Of special interest are chemically active inhibitors producing a noticeable effect on flame at low concentrations, which do not change the flame stoichiometry. Thousands of elementary reactions involving hundreds of species proceed in hydrocarbon flame. However, the key reactions are those involving atoms and free radicals; with their reaction rates being much faster than those of the other reactions. The inhibitors mainly interact and affect the above processes.

Diazotization of 2-acetylenic derivatives of 1-aminoanthraquinone followed by intramolecular cyclization leads to the formation in good yields of 1H-3-acyl- or 1H-3-(1,1-dichloroalkyl)naphtho[2,3-g]indazole-6,11-diones, rather than 3-substituted 4-hydroxynahtho[2,3-h]cinnoline-7,12-diones, the normal Richter synthesis products.

Reaction of 1-acetylenic derivatives of anthraquinone with hydrazine affording substituted 4 H -anthra [9, 1-cd] -1,2-diazepin-8-ones and 7H-dibenzo [de, h] quinolin-7-ones is reported.

A general method for the synthesis of substituted fused polycyclic compounds containing a 4-alkylamino or 4-dialkylaminopyridine cycle has been proposed. The method includes the addition of primary or secondary amines to vicinal (acylethynyl)arylamines followed by the cyclization of the adducts under acidic or basic catalysis conditions. Various aminonaphthoquinolinediones and aminoquinolines have been prepared in high yields by this method.

2-Alkynyl-l-amino-9,10-anthraquinones react with HNO2 in a mixture of dilute HCl and dioxane at 20 °C to give I , 1-dichloroalkyl- IH-3-naphto[2,3-g]indazole-6,1 1 -diones. This reaction differs from the known cylization ofortho-alkynylbenzenediazonium salts involving the formation of a pyridazine ring (the Richter synthesis of 4-hydroxy- and 4-halocinnolines).

Syntheses are reported for 9,10-bis(phenylethynyl)anthracene and its derivatives containing identical and different substituants in the phenyl groups by the acetylenic condensation of 9,10-dibromoanthracene. The introduction of a donor substituent into one phenyl group and a withdrawing substituent into the other leads to a significant shift of the fluorescence maximum toward longer wavelengths.

A method is suggested for isomerization of α-acetylenic ketones with migration of the oxo group from position 1 to position 3 and of the triple bond from position 2 to position 1 of the ketoacetylenic fragment; it consists of addition of Et2NH at the triple bond of the ketone, conversion of the adduct to the imminium salt with POCl3, followed by alkaline hydrolysis. The isomerization is achieved in one preparative stage without isolation of intermediate compounds.