Synthesis of Pyrimido[6,1-a]isoquinolines by the Reaction of Thriethyl Orthoformate with Enamines of 3,3-dialkyl-1,2,3,4-tetrahydroisoquinoline series

Russian Journal of Organic Chemistry - Boiling (Z)-2-[3,3-dimethyl-3,4-dihydroisoquinolin-1(2H)-ylidene]acetamides in AcOEt/Ac2O leads involves annelation of the pyrimidine ring to form...     

The Annelation for Enaminoureides of 3,3-Dimethyl-1,2,3,4-tetrahydroisoquinoline Series by Action of Oxalyl Chloride and Ninhydrin

By reaction of Ritter cyclization of cyanoacetylureas with dimethylbenzylcarbinoles the corresponding enaminoureides were obtained, derivatives of 3,3-dimethyl-1,2,3,4-tetrahydroisoquinoline. The polyfunctional character of obtained compounds is confirmed by the structure of products of reaction with some electrophiles: phenyl isocyanate reacts at the γ-C atom of enamine and CONH₂ group of urea, under the action of oxalyl chloride annelation of a pyrrole cycle occurs with the formation of a derivative of 2,3-dioxopyrrolo[2,1-a]isoquinoline. Reaction with ninhydrin occurs similary with enaminoamides having hydrogen atoms at the amide nitrogen: a pyrrole ring is fused with the formation of a system of indeno[1,2-b]pyrrole.     

Molecular Layer Deposition of Silicon Nitride with Glow Discharge Activation

Russian Journal of Physical Chemistry A - The formation of silicon-nitrogen nanolayers obtained by molecular layer deposition on the GaAs surface with (100) and (110) orientations in the...     

Reactions of 2,3-dioxopyrrolo[2,1-<Emphasis Type="Italic">a</Emphasis>]isoquinolinecarboxylic acid esters and amides with nitrogen-centered nucleophiles

Reactions of ethyl 2,3-dioxopyrrolo[2,1-a]isoquinoline-1-carboxylates with active nitrogen-centered nucleophiles (phenylhydrazine, hydroxylamine, and benzylamine) involve opening of the pyrrole ring with formation of 2-(3,3-dimethyl-1,2,3,4-tetrahydroisoquinolin-1-ylidene)-N′¹,N′⁴-diphenyl-3-(2-phenylhydrazono) succinohydrazide, 5-(6,7-dimethoxy-3,3-dimethyl-1,2,3,4-tetrahydroisoquinolin-1-ylidene)-2,3,4,5-tetrahydro-1H-1,2-oxazine-3,4,6-trione, and ethyl 4-benzylamino-2-(3,3-dimethyl-1,2,3,4-tetrahydroisoquinolin-1-ylidene)-3,4-dioxobutanoate, respectively. Cyclic amides derived from 5,5-dimethyl-2,3-dioxo-2,3,5,6-tetrahydropyrrolo[2,1-a]isoquinoline-1-carboxylic acid react with benzylamine in a similar way. Reactions of the title compounds with weaker nucleophiles, such as semicarbazide and thiosemicarbazide, are not accompanied by opening of the pyrrole ring, and the products are the corresponding semicarbazones and thiosemicarbazones at the C²=O carbonyl group.     

The role of Laplace pressure in the formation of the structure of thin layers based on silicon dioxide

Formation of the structure of thin layers deposited from the gas phase occurs not only during film deposition but also during the subsequent annealing. In the present work, porous films were deposited using the catalytic chemical vapor deposition (Cat-CVD) procedure. It was shown that the kinetics of a decrease in the film volume during annealing can be explained taking into account the role of Laplace pressure in the formed pores.     

Infinitesimal,first order bendings of smooth,convex surfaces of revolution subject to conic,sleeve-like constraints along the boundary

We prove that on a closed, smooth, convex surface of revolution , whose poles are not flattening points, there exists only a countable set of parallels _n. Each of these parallels cuts surface into two parts so that one of the parts, , admits nontrivial, infinitesimal bendings in the process of which all the points of its boundary _n are displaced on a preassigned, conic sleeve K that is coaxial with the surface. The sequence of such parallels _n converges to parallel ^*, which has the following properties: 1) the tangent cone to surface along ^* is orthogonal to sleeve K; 2) surface , cut off from surface by parallel ^*, has rigidity of first order in the indicated class of bendings.Translated from Ukrainskii Geometricheskii Sbornik, No. 33, pp. 3–8, 1990.     

Pyrrolo[2,1-a]isoquinolines (review)

Published data on the synthesis of compounds containing the pyrrolo[2,1-a]isoquinoline system in their structure are reviewed. Examples of substances that have useful properties for practical purposes are given.Institute of Technical Chemistry, Urals Branch, Russian Academy of Sciences, Perm'. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 291–317, March, 1997.     

Synthesis and properties of hydrazones of the phenanthridine series

The reaction of 6-hydrazinophenanthridine with carbonyl reagents gave hydrazones, while the reaction with formic acid gave a 1,2,4-triazole derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 531–534, April, 1992.     

Synthesis and acylation of tertiary enamines: 1,2,3,4-tetrahydroisoquinoline derivatives

N-methyl-3,3-R¹R²-1-(R³-methylene)-1,2,3,4-tetrahydroisoquinolines were obtained; they react with acylating agents forming enaminocarbonyl derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 939–942, July, 1988.