Indolo[3,3a,4-gh]chinoline und 10a, 6a-Iminopropano-indolo-[3,3a,4-gh]chinoline. Stereospezifische Synthesen und Umlagerungen. Teil II. 9. Mitteilung über synthetische Indolverbindungen

Alkaline hydrolysis of 1-benzyl-4, 4-dicyanoethyl-5-oxo-1,3,4,5-tetrahydro-benzo-[cd]indole under controlled conditions leads to 4-benzyl-4,6,7,8-tetrahydro-10a, 6a-iminopropanoindolo[3,3a,4-gh]quinoline-9(10H),12-dione ( 2a ), the first representative of such a ring system. Alkylation of this di-lactam affords the N-monoalkyl ( 2b ), the N, N'-dialkyl ( 3 ), and the N, O-dialkyl ( 4 ) derivatives according to the conditions employed. Treatment of compounds such as 2 with sodium in liquid ammonia results in the opening of one of the lactam rings by a stereoelectronically controlled reductive cleavage of the benzylamine bond; subsequent protonation proceeds stereospecifically to give trans-octahydroindolo[3,3a, 4-gh]quinolines (viz. 5 ). The NMR. spectra and the mechanism of the reductive ring opening are discussed.     

Beiträge zur Chemie der Pyrrolo[3,2-c]azepine und der Pyrrolo [3,2-b]azepine

Some chemical transformations in the series of the pyrrolo [3,2-b]azepines and the pyrrolo[3,2-c]azepines are reported: alkylation at the pyrrolo nitrogen and/or the azepino nitrogen, reduction of the lactam group by means of LiAlH₄, preparation of lactim ethers and amidines, substitution in position 2 by MANNICH reaction, bromination and condensation with oxalyl chloride or chloral hydrate, and the cyclocondensation with dimethylmalonyl chloride. The structures of the 2-substitution products have been evaluated by NMR.-spectroscopy.     

Notiz über einen Zugang zu β, γ-ungesättigten Carbonsäurederivaten mit Hilfe der Amidacetal-Claisenumlagerung. Über synthetische methoden, 17. Mitteilung

Note on a preparation of β, γ-unsaturated carboxylic acid derivatives using the amide acetal Claisen rearrangement 3-(Trimethylsilyl)allyl alcohols smoothly undergo the amide acetal Claisen rearrangement furnishing allyl silanes. Subsequent protolysis with HF at ?20° provides a convenient, stereoselective method for the preparation of β, γ-unsaturated carboxylic acid derivatives. Three model examples illustrate the procedure.     

Photocyclisierung von 1-[3-(Chloracetylamino)propyl]-3-methylindol. 12. Mitteilung über synthetische Indol-Verbindungen

Photochemical cyclization of 1-[3-(chloroacetylamino)propyl]-3-methyl-indole . Photochemical cyclization of 1-[3-(chloroacetylamino)propyl]-3-methyl-indole involving loss of HCl leads to the three isomers 2, 3 and 4 , the structures of which have been determined by physical and chemical methods.     

Ringschlüsse an Chinonylmethanfarbstoffen und analogen Merocyaninen. 6. Mitteilung. Über die Reaktivität des Cyclohexylrestes in 2-Chlor-3-[(1-cyclohexyl-6-fluor-3-methyl-1H-chinoxalin-2-yliden)methyl]-1,4-naphthochinon

Ring Closure in Quinonylmethane Dyes On the Reactivity of the Cyciohexyl Moiety in 2-Chloro-3-[(1-cyclohexyl-6-fluoro-3-methyl-1H-quinoxalin-2-ylidene)niethyl]-1,4-naphthoquinonc The reactive title compound ( 1a , X = F , R ¹ = C⁶H¹¹, R ²=Cl) was obtained from the reaction of 1-cyclohexyl-6-fluoro-2,3-dimethylquinoxalinium perchlorate with 2,3-dichloro-1,4-naphthoquinone. Upon treatment with pyridine and acetic acid in acetone and separation of the desired naphthophenazinone 2a , an unexpected azepinoquinoxaline 4a was isolated. The structure of 4a was determined by its mass and 360-MHz-¹H-NMR. spectra in connection with decoupling experiments.     

Some remarks on computer-aided design of optical lens systems

Computer-aided design of optical lens systems implies the solution of an optimization problem of large dimension. To apply a local algorithm, we want to know a starting point within a small neighborhood of the desired system. For a given task, the designer is not able to define a suitable starting point. In this paper, we describe a global optimization algorithm which uses the principles of biological evolution with the aim of locating an adequate starting point for a local correction routine.This work was supported by the Department of Mathematics, Friedrich Schiller University, Jena, GDR, in cooperation with the research center of VEB Kombinat Carl Zeiss, Jena, GDR. The authors are indebted to Dr. L. C. W. Dixon for discussions of the topic.     

Synthese Eines Optisch Aktiven Penem-Zwischenprodukts Mittels Asymmetrischer Amidoalkylierung

Synthesis of an Optically Active Penem Intermediate by Asymmetric Amidoalkylation The amidoalkylation of an optically active, cationic glycine derivative with methyl acetoacetate furnishes an intermediate 10a (Scheme 2) that is transformed in six steps to the optically active, silyl-protected 4-acetoxy-3-(1-hydroxyenthyl)-2-azetidinon 18a , a well known intermediate in penem synthesis.     

Messungen des freien und inkohärenten Neutronenwirkungsquerschnitts an Silizium und Blei

The free neutron cross section of Silicone and Lead has been determined to (2.022 ± 0.003) barns and (10.58 ± 0.03) barns respectively and the incoherent cross section of the same elements to (15 ± 1.3) · 10^?3 barns and (15 ± 15) · 10^?3 barns respectively. From these results the coherent cross sections have been calculated under consideration of various correction terms to (2.153 ± 0.005) barns and (10.65 ± 0.05) barns.