Arbeiten über Phosphorsäure- und Thiophosphorsäureester mit einem heterocyclischen Substituenten. 3. Mitteilung. Thiadiazol-Ringschluss und eine dabei auftretende Methylübertragung

Methods for the synthesis of 5-alkoxy- and 5-alkylthio-1,3,4-thiadiazol-2(3H)-ones and -thiones, known in principle, are extended and adapted for large scale preparations. In the particular case of 5-methoxy-1,3,4-thiadiazol-2(3H)-thione the cyclisation of thiocarbazic O-methyl ester using alcoholic alkali and carbon disulfide added in this order surprisingly yields by transmethylation 5-methylthio-1,3,4-thiadiazol-2(3H)-one, isomer of the expected 5-methoxy-1,3,4-thiadiazol-2(3H)-thione. This latter compound is obtained when the reactants are applied in the inverse sequence. A possible mechanism for this behaviour is presented.     

Arbeiten über Phosphorsäure- und Thiophosphorsäureester mit einem heterocyclischen Substituenten. 4. Mitteilung. 3-Isopropyliden-dithiocarbazinsäure-alkylester und deren Ringschluss zu 5-Alkylthio-1,3,4-thiadiazol-2(3H)-onen

Impurities in crude oily dithiocarbazic acid (2′-methoxy)-ethyl ester causing troubles in the ring closure to 5-(2′-methoxy-ethylthio)-1,3,4-thiadiazol-2(3H)-one and in succeeding reactions are eliminated by using the crystalline 3-isopropylidene-dithiocarbazic acid (2′-methoxy)-ethyl ester, which can be obtained directly by alkylation of potassium dithiocarbazate with 2-methoxy-ethyl bromide in presence of acetone. By the action of phosgene followed by that of water, the isopropylidene compound yields the oily 5-(2′-methoxy-ethylthio)-1,3,4-thiadiazol-2(3H)-one by splitting off the isopropylidene group and by ring closure in one single step.     

Arbeiten über Phosphorsäure und Thiophosphorsäureester mit einem heterocyclischen Substituenten 9. Mitteilung 1. Aza-Analogie I: Aza-Analoge von Phthalimid-, Benztriazol- und 1,2,3-Benztriazin-4(3H)-on-Derivaten

Aza-analogues of the known pesticidal dithiophosphates 2, 4 and 5 have been prepared by replacing the phthalimide, benzotriazole and 1,2,3-benzotriazin-4(3H)-one moieties resp. in 2 by those of quinolinic acid imide (6), cinchomeronic acid imide (7) and pyrazine-2,3-dicarboxylic acid imide (12), in 4 by 1H-v-triazolo[4,5-b]pyridine (15) and in 5 by pyrido[2,3-e]1,2,3-triazin-4(3H)-one (21). Compared to the known compounds the new esters are less or at best equally pesticidal with an equal or even higher mammalian toxicity.     

Arbeiten über Phosphorsäure- und Thiophosphorsäure ester mit einem heterocyclischen Substituenten. 2. Mitteilung. Eine verbesserte Methode zur Herstellung von 1, 3, 4-Oxadiazol-2(3H) onen und von Thio- und Dithiophosphorsäure-O,O-dialkyl-S-[(1, 3, 4-oxadiazol-2(3H)-on-3-yl)-methyl]-estern

Some 1,3,4-oxadiazol-2(2H)-ones with aliphatic substituents in 5-position are prepared in good yields and converted via the 3-hydroxymethyl derivatives to the corresponding 3-chloromethyl derivatives which are suitable starting materials for the preparation of insecticidal O,O-dialkyl-S-[(5-subst.-1,3,4-oxidiazol-2(3H)-one-3-yl)-methyl]-thiophosphates and dithiophosphates.     

Cyclische Phosphorsäure- und Thiophosphorsäurederivate aus den Säuredihydraziden und bifunktionellen Siloxanen Neue anorganische Heterocyclen mit bis zu zehn Ringgliedern

Cyclic Derivatives of Phosphoric and Thiophosphoric Acid from the Corresponding Acid Dihydrazides and Bifunctional Siloxanes. New Inorganic Heterocycles with up to Ten Ring Members Dihydrazidophosphoric and dihydrazidothiophosphoric acid phenylester react with α, Ω-dichloroorganodisiloxanes and -trisiloxanes in the presence of triethylamine as a base yielding ring compounds. With dichlorotetraphenyldisiloxane a six-membered ring with two exocyclic NH₂ groups, a seven-membered ring with only one exocyclic NH₂ group and an eight-membered ring without such groups are formed. With dichlorohexamethyltrisiloxane corresponding mixtures of eight-, nine-, and ten-membered rings are obtained. Five new ring compounds could be isolated as pure isomers by fractional crystallization and have been characterized by analysis and spectroscopic methods.     

Notiz zum massenspektrometrischen Zerfall monohalogenierter Essigsäuren und Essigsäureester. 36. Mitteilung über massenspektrometrische Untersuchungen

Note on the Mass Spectral Decomposition of Monohalogenated Acetic Acids and its Esters Besides the well known ester fragmentation reactions two unusual decomposition reactions are observed in the mass spectra of the title compounds, leading to the ions [M-CO₂]⁺ and [M-HX]⁺. The rearrangement reactions involved in the formation of these ions are discussed.     

Die Aminoalkylierung von Phtalazinen und Phtalazonen mit Hilfe der GRIGNARD-Reaktion. 4. Mitteilung über GRIGNARD-Reaktionen mit Halogenalkylaminen [1]

Phtalazines and 4(3H)-phthalazones are aminoalkylated in high yield by 3-dimethylaminopropyl-magnesiumchloride. Phthalazines add only one molecule of the GRIGNARD reagent at the C?N-double bond, giving mono-aminoalkylated 1,2-dihydrophthalazines which undergo no further reaction without previous oxydation. Phthalazones react with the carbonyl and the C?N-group yielding in one step di-aminoalkylated dihydrophthalazines. The dihydrophthalazines are easily oxydized with K₃Fe(CN)₆ to the corresponding phthalazines.     

Massenspektrometrische Identifizierung und Synthese isomerer und homologer Spermidin- und Spermin-Derivate. 25. Mitteilung über das massenspektrometrische Verhalten von Stickstoffverbindungen. 161. Mitteilung über Alkaloide

Synthesis of isomeric and homologous spermidine and spermine derivatives and their identification by mass spectrometry. The structure of homologous and isomeric spermidines and spermines follows from mass-spectroscopical analysis of their peracetyl (see text, footnote 3) (Table 1) or tosyl-acetyl (Table 2) derivatives. In the case of the peracetyl compounds, triads of peaks are recorded which, according to the number of methylene groups between the nitrogen atoms, show mass numbers characteristic for each of the substances (Scheme 1, ions b , d , e and c ). On the basis of cyclic ions of type f (Scheme 2), occurring in the mass spectra of N-acetyl derivatives, tosylated on a secondary amino nitrogen atom, deductions can be drawn as to the number of methylene groups between neighbouring tosylated and acetylated nitrogen atoms in these compounds.     

Über eine Ringerweiterungsreaktion an einem Barbitursäure-Derivat. 10. Mitteilung über Umamidierungsreaktionen

A Ring Enlargement Reaction with a Barbiturate The (6-membered) barbituric acid derivative 3 was synthesized and treated with KF/DMF/18-crown-6 to form the ring-enlarged 14-membered compound 8 in good yield.     

Zur Kristallstruktur von SmZrF7 mit einem Anhang über EuSnF7 und YSnF7

On the Crystal Structure of SmZrF₇ with an Appendix on EuSnF₇ and YSnF₇ SmZrF₇ again was obtained as colourless single crystals and investigated by X-ray methods: It crystallizes in space group P 2₁/c-C (Nr. 14; P 2₁/n) with a = 1 140.9(2) pm, b = 574.6(1) pm, c = 914,4(2) pm, β = 107.32(2)°, Z = 4 but not in space group P 2₁-C (Nr. 4) [1]. In addition EuSnF₇ and YSnF₇ are isotypic with the following lattice constants: EuSnF₇: a = 1 121.8(2) pm, b = 563.7(1) pm, c = 901.7(1) pm, β = 107.35(2)° with Z = 4; YSnF₇: a = 1 106.7(2) pm, b = 556.4(1) pm, c = 884.7(1) pm, β = 107.51(1)° and Z = 4 (Powder data).     

Anil-Synthese 22. Mitteilung über die Herstellung von Styryl-und Distyryl-Derivaten des Pyridins

Preparation of Styryl and Distyryl Derivatives of Pyridine 2,4-, 2,5- and 2,6-Dimethylpyridines react with anils of aromatic aldehydes in the presence of dimethylformamide and potassium hydroxide to yield the corresponding distyrylpyridines (‘anil synthesis’). Under the same reaction conditions (4-methylstyryl)pyridines are converted to (stilbenylvinyl)pyridines. Similarly, the Schiff's base derived from pyridine-3-carbaldehyde and p-chloroaniline on treatment with methyl- and p-tolyl-substituted aromatic heterocycles gives the corresponding (heteroaryl-styryl)pyridines, whereas with the Schiff's bases derived from pyridine-2- and -4-carbaldehyde side reactions, such as dimerization followed by disproportionation predominate.     

Über Chalkogenolate. 133. Untersuchungen über Ester von Halogenoameisensäuren 1. Chloroameisensäure-, Chloromonothioameisensäure- und Chlorodithioameisensäurealkylester

On Chalcogenolates. 133. Studies on Esters of Haloformic Acids. 1. Alkyl Esters of Chloroformic, Chloromonothioformic, and Chlorodithioformic Acids The prepared esters RO? CO? Cl, RS? CO? Cl, RO? CS? Cl, and RS? CS? Cl with R = alkyl have been characterized by means of electron absorption, infrared, nuclear magnetic resonance, and mass spectra.     

Oxydative Kupplung von Indolinen und 1,2,3,4-Tetrahydrochinolinen mit Kaliumpermanganat. 153. Mitteilung über Alkaloide

It is shown that treatment of indolines like 4a-methyl-1,2,3,4,4a,9a-hexahydrocarbazole ( 1 ) and even indoline-alkaloids like 5 or 6 (cf. scheme 1) with KMnO₄ in boiling acetone solution leads to the indolenines 10, 29 and 33 , respectively, and, in relatively high yields, to N,N′- or C,N-coupling products (cf. schemes 2 and 5). The results of the oxidation of 6- or 8-methoxy-indolines are shown in schemes 3 and 4, respectively. Analogous ‘dimeric’ dehydrogenation products are observed when tetrahydroquinolines ( 8 and 9 , resp.) are treated with KMnO₄ (cf. schemes 7 and 8, resp.). The formation of the bis-compounds is almost certainly due to the coupling of two intermediate indolenyl or tetrahydroquinolyl radicals. The cleavage of the hydrazine derivatives 11 or 17 (scheme 9) also leads to ‘dimeric’ C,N-coupling products. By heating the hydrazine derivative 17 with aqueous HCl, a complete cleavage into indoline 2 and the indolenines 16 and 20 is observed. The reaction is rationalized in scheme 10. So far no naturally occurring alkaloids related to the above mentioned C,N-coupling products have been found.     

Der Einfluss von Dimethylsulfoxid und Dioxan auf die Reaktionen von 2,4-Dinitrofluorbenzol und 2,4-Dinitrochlorbenzol mit Piperidin in Benzol. 4. Mitteilung über nucleophile aromatische Substitutionsreaktionen

(1) The rates of the reactions of 2,4-dinitrofluoro- and 2,4-dinitrochlorobenzene with piperidine as influenced by the addition of dimethylsulfoxide and p-dioxane have been measured in benzene solution.     

Photochemische Cycloadditionen von 3-phenyl-2h-azirinen mit Aldehyden. 31. Mitteilung über Photoreaktionen

Experiments concerning the photochemical condensation of 3-phenyl-2H-azirines 1 with aliphatic and aromatic aldehydes to 3-oxazolines 4 are fully described (cf. scheme 1 ). Photochemically nitrile methylides of type 2 are first formed, which then very quickly react thermally with the aldehydes in a regiospecific manner to give the 3-oxazolines 4 . Azirines monosubstituted in position 2 (l b and 1 c ) give mixtures of cis, trans-oxazoline isomers, in which the cis isomer predominates. The stereoselectivity of the cycloaddition reaction can be rationalized by a simple model (scheme 10). The stereoisomeric 3-oxazolines 4 are distinguishable in the NMR. spectra by the large homoallylic coupling constants between the H atoms on C(2) and C(5).     

Die Aminoalkylierung von Chinoxalinen und Chinoxalonen 6. Mitteilung über grignard-reaktionen mit halogenalkylaminen [1]

Quinoxaline and 2(1H)-quinoxalones react with organomagnesium salts differently from the corresponding phthalazines and quinazolines. 3-Dimethylaminopropyl-magnesiumchloride alkylates quinoxaline easily by addition to the 2 and 3 position forming a tetrahydroquinoxaline 2 , which can be dehydrogenated to the corresponding dialkylated quinoxaline 3 . The monosubstituted dihydroquinoxaline 5 is obtained only with difficulty. It can equally be dehydrogenated, yielding 6 . Quinoxalones react with CH₃MgI, C₆H₅MgBr, (CH₃)₂N? (CH₂)₃? MgCl by addition to the 3,4-C?N bond (not at the CO-group), yielding 11–13 . These dihydroquinoxalones are dehydrogenated to the 3-substituted 2(1H)-quinoxalones 14–16 . Only 3-phenyl-quinoxalone adds a Grignard reagent at the CO group, forming a 2-substituted 3-phenylquinoxaline ( 26 ). 3-Methyl-quinoxalone exhibits an abnormal behaviour: It is deprotonated by the mentioned reagents at the CH3 group, and the 3-methylenequinoxalone-anion so formed attacks another molecule of methylquinoxalone, finally yielding 32 and 33 .     

Photochemische Cycloadditionen von 3-Phenyl-2H-azirinen mit Benzoyl-, Äthoxycarbonyl- und Vinylphosphonaten 34. Mitteilung über Photoreaktionen

The irradiation of the 3-phenyl-2H-azirines 1a–c in the presence of diethyl benzoylphosphonate ( 8 ) in cyclonexane solution, using a mercury high pressure lamp (pyrex filter), yields the diethyl (4, 5-diphenyl-3-oxazolin-5-yl)-phosphonates 9a–c (Scheme 3). In the case of 1b a mixture of two diastereomeric 3-oxazolines, resulting from a regiospecific but non-stereospecific cycloaddition of the benzonitrile-benzylide dipole 2b to the carbonyl group of the phosphonate 8 , was isolated. Benzonitrile-isopropylide ( 2a ), generated from 2,2-dimethyl-3-phenyl-2H-azirine ( 1a ), undergoes a cycloaddition reaction to the ester-carbonyl group of diethyl ethoxycarbonylphosphonate ( 15 ) with the same regiospecificity to give the 3-oxazoline derivative 16 (Scheme 5). The azirines 1a–c , on irradiation in benzene in the presence of diethyl vinylphosphonate ( 17 ) give non-regiospecifically the Δ¹-pyrrolines 13a–c and 14a–c (Scheme 6).     

Reaktionen von Bleitetraacetat mit alicyclischen Alkoholen,III. Cyclopropyl- und Cyclobutylcarbinole. 18. Mitteilung über Reaktionen mit Bleitetraacetat

When treated with lead tetraacetate, cyclopropylcarbinol and cyclopropylmethylcarbinol do not give β-fragmentation products resulting from the intermediate formation of cyclopropyl radicals; however, cyclopropylmethylcarbinol affords a small amount of a fragmentation product which arises from C_α? C_β bond cleavage involving removal of a methyl radical. In contrast, cyclobutylcarbinol undergoes β-fragmentation in 18% yield with formation of both the unrearranged cyclobutyl acetate and the rearranged cyclopropylmethyl acetate. These results suggest the following order of increasing radical stability: cyclopropyl < methyl < cyclobutyl, whereas the isolation of the isomeric fragmentation acetates in the lead tetraacetate reaction of cyclobutylcarbinol represents further evidence that in the β-fragmentation process the initially produced carbon radical fragment is in major part oxidized to the corresponding carbonium ion before final product formation.