Imidazol-4-carbinole aus Iminoestern und Dihydroxyaceton. 2. Mitt. über Imidazolsynthesen mit flüssigem Ammoniak

Imidazole-4-carbinols from Iminoesters and Dihydroxyacetone Imidazole-4-carbinols 3 with functional groups at C-atom 2 are obtained from iminoesters 1 and dihydroxyacetone ( 2 ) in liquid ammonia under pressure.     

Imidazolsynthesen,Mitt. Synthese α-substituierter 4(5)-Methoxymethyl-5(4)-methyl-imidazole

Synthesis of α-Substituted 4(5)-Methoxymethyl-5(4)-methylimidazoles Methoxymercuration of the α,β-unsaturated ketones 1 produces the α-acetoxymercury-β-methoxyketones 2 , which are bromo-demercurised without isolation to give the α-bromo-β-methoxyketones 3 . Cyclisation of 3 with formamidine acetate in liquid ammonia leads to α-substituted 4(5)-methoxymethyl-5(4)-methylimidazoles 4 , the structures of which are proved by ¹³C-NMR spectroscopy.     

Synthesen mit Nitrilen, 71. Mitt. Zur Synthese von 4-Hydroxynicotinsäure aus Butadiendicarbonitrilen

Syntheses with Nitriles LXXI: Synthesis of 4-Hydroxynicotinic Acid from Butadienedicarbonitriles Condensation of 1,1-dicyano-2-ethoxy-1-propene (1) with dimethylformamide dimethylacetal leads to butadienedicarbonitriles 2 . Ring closure of 2 with hydrogen halides or ammonia yields 4-alkoxy-2-halo-(or 2-amino)pyridine-3-carbonitriles 3 or 5 . Catalytic reduction of 3 yields 4-alkoxypyridine-3-carbonitriles, which can be converted to 4-hydroxynicotinic acid (9) by treatment with conc. hydrochloric acid.     

Zur Aminolyse von trans-3-Phenylglycidsäure-Derivaten, 5. Mitt. Unterscheidung N-substituierter 3-Phenylserin- und 3-Phenylisoserin-Derivate

Aminolysis of Derivatives of trans-3-Phenylglycidic Acid, V: Distinction Between N-Substituted Derivatives of 3-Phenylserine and 3-Phenylisoserine Derivatives of trans-3-phenylglycidic acid react with primary and secondary aliphatic amines to give derivatives of erythro-3-phenylisoserine. Hydrogenolysis of the N-benzyl or O-benzyl moiety allows better than other methods to distinguish between derivatives of 3-phenylserine and 3-phenylisoserine. The structural proof reported in⁵⁾ is not correct.     

Untersuchungen an 1,3-Thiazinen, 38. Mitt.: Iminiumkohlensäurederivat-Salze, 2. Mitt.: Synthese N-substituierter 2-Chlor-5,6-dihydro-4H-1,3-thiazinium-salze und deren Reaktionen mit primären Aminoverbindungen

Synthesis of N-Substituted 2-Chloro-5,6-dihydro-4H-1,3-thiazinium Salts and Their Reactions with Primary Amino Compounds After a short review of synthesis and reactions of halogeno(organothio)methaniminiumsalts, the reactions of tetrahydro-1,3-thiazine-2-thiones 9 with thionyl chloride or phosgene to yield 2-chloro-5,6-dihydro-4H-1,3-thiazinium chlorides 10 are described. Compounds 10 can be converted to the more stable tetrafluoroborates 13 and hexafluorophosphates 12 , which can be conveniently characterized. Chloroiminium chlorides 10 generated in situ, react with primary amino compounds such as aliphatic or aromatic amines, carboxamides, sulfonamides, diphenylphosphinamide, cyanamide or N-substituted ureas to yield the N,N′-disubstituted 2-iminotetrahydro-1,3-thiazines 17 – 24 .     

Synthese von substituierten Indol-Derivaten, 2. Mitt. Zur Reaktivität eines cyclischen Chinon-Halbaminals

Synthesis of Substituted Indole Derivatives, II: The Reactivity of a Cyclic Quinonecarbinolamine The cyclic quinonecarbinolamine 1 reacts with basic nucleophiles to yield the indolemethylene derivatives 3 via an enol tautomer of 1 .     

Synthese von Phosphorsäurephenylesterdiamiden, 1. Mitt.

Synthesis of Phenyl Phosphorodiamidates, I Two procedures are described for the synthesis of phenyl phosphorodiamidates in high yields. These compounds can be represented by the general formula 6 and are used for cyclisation reactions leading to phosphabarbituric acids.     

Zur Synthese N-monosubstituierter O-Acylhydroxylamine. 38. Mitt. über Hydroxylamin-Derivate

Hydroxylamine Derivatives. Part 38 The synthesis of N-monosubstituted O-acylhydroxylamines is possible by using the Bocprotective function.     

Zur Synthese des Hexöstrol-Isosteren meso-N,N′-Dimethyl-α,α'-di-(4-hydroxyphenyl)-äthylendiamin. 13. Mitt.: Über Cytostatica

Synthesis of meso-N,N′-Dimethyl-α,α'-di-(4-hydroxyphenyl)-ethylenediamine The reaction of 4-methoxybenzylidenemethylamine with activated aluminium in ethanol yields rac.- und meso-N,N′-Dimethyl-α',-di-(4-methoxyphenyl)-ethylenediamine besides a higher molecular resinous compound, 4-methoxybenzylmethylamine, rac.- and meso- 1,3-dimethyl-2,4,5-tri-(4′-methoxyphenyl)-imidazolidine. The isolation of the individual compounds was achieved by Craig distribution. Ether cleavage of rac.- and meso-N,N′-dimethyl-α,α'-di-(4-methoxyphenyl)-ethylenediamine yields rac.- and meso-N,N′-dimethyl-α,α'-di-(4-hydroxyphenyl)-ethylenediamine, the latter being isosteric to hexestrol.     

Imidazolsynthesen, 8. Mitt.: N-Substituierte Imidazole nach Weidenhagen

Weidenhagen Synthesis of N-Substituted Imidazoles The Weidenhagen synthesis of N-unsubstituted imidazoles from α-substituted carbonyl compounds 1 , aldehydes 3 , and aqueous ammonia ( 4 ) with copper (II) salts as oxidizing agents is also usable for the synthesis of N-substituted imidazoles 6 through the addition of primary amines 5 .     

Indole, 2. Mitt. Zur Synthese von 1,3,4-Oxadiazolyl- und Pyrazolcarbonylindolen

Indoles, II: Synthesis of 1,3,4-Oxadiazolylindoles and Indolyl(pyrazolyl)methanones Condensations of 5-chloroindole-2-carbohydrazide (1) with the aldehydes 2a–k yield the acylhydrazones 3a-k . Treatment of 3a–h with boiling acetic anhydride results in the formation of the N-acetyl-1,3,4-oxadiazolylindoles 4a–h within 15 min. Cyclisation of 3i–k requires longer reaction times and gives the N,N′-diacetyloxadiazolylindoles 5i–j . Depending on the type of the p-dicarbonyl compound, the reaction with 1 in boiling toluene/p-toluenesulfonic acid gives indolyl(pyrazolyl)methanones 8a, b , hydrazone 8c or unchanged 1 .     

Zur Stereochemie der 3-Oxo-5-phenyl-1-cyclopentancarbonsäuren, 5. Mitt. Zur stereoselektiven Synthese der stereomeren 5-Phenyl-dihydroisosarkomycine

Stereochemistry of 3-Oxo-5-phenylcyclopentanecarboxylic Acids, V: On the Stereoselective Synthesis of the Stereomeric 5-Phenyldihydrosarcomycines In connection with our attempts to synthesize stereoselectively the 5-phenyldihydroisosarcomycines 1–4 , the C-methylation of 3-oxo-t-5-phenyl-1,1,r-4-cyclopentanetricarboxylic acid trimethylester (5) was performed. The reaction yields t-4-methyl-3-oxo-c-5-phenyl-1,1,r-4-cyclopentanetricarboxylic acid trimethylester (7) with a high degree of stereoselectivity. The stepwise degradation of 7 by acidic or basic saponification and decarboxylation has been examined. Via the isolated intermediates t-1,t-4-dimethoxycarbonyl-c-4-methyl-3-oxo-t-5-phenyl-r-1-cyclopentanecarboxylic acid (10) and c-4-methoxycarbonyl-t-4-methyl-3-oxo-c-5-phenyl-r-1-cyclopentanecarboxylic acid (12) the acid 1 (t-4-methyl-3-oxo-c-5-phenyl-r-1-cyclopentanecarboxylic acid) was obtained stereoselectively. The trans-carboxylic acid (c-4-methyl-3-oxo-t-5-phenyl-r-1-cyclopentanecarboxylic acid) (3) is accessible by thermodynamically controlled rearrangement.     

Zur Synthese des Phaeantharins, 1. Mitt. Syntheseplan für Phaeantharin und Synthese des Bausteines A: 4′,5-Dibrommethyl-2-methoxydiphenylether

On the Synthesis of Phaeantharine, I: Plan of the Synthesis of Phaeantharine and Synthesis of the Unit A: 4′,5-Bis(bromomethyl)-2-methoxydiphenyl Ether A plan for the synthesis of phaeantharine is proposed. The 4′,5-bis(bromomethyl)-2-methoxydiphenyl ether (5) , required for this approach, was prepared in three steps from 4-bromobenzaldehyde (1) and 3-hydroxy-4-methoxybenzaldehyde (2) via the diformyldiphenyl ether 3 and the diol 4 with a total yield of 46%.     

NMR-Spektroskopie an Heterocyclen, 5. Mitt. 13C-NMR- und massenspektrometrische Untersuchung N-substituierter Methoxy- und Hydroxy-äthylimidazole

NMR-Spectroscopy of Heterocyclic Compounds, V: ¹³C-NMR and Mass Spectrometry of N-Substituted (2-Methoxyethyl)- and (2-Hydroxyethyl)-imidazoles The ¹³C-NMR and mass spectra of various N-substituted (2-methoxyethyl)- and (2-hydroxyethyl)imidazoles are described. A scheme for the fragmentation of 1,2-diethyl-4-(2-hydroxyethyl)imidazole is reported.