Zur Chemie der 2,4-Diaminothiopyranyliumjodide Synthese von α,β,γ,δ-ungesättigten Thiocarbonsäureamiden

Aminolysis of 4-dialkylamino- and 4-alkylamino-2-methylthiothiopyranyliden iodides2 resp. under various reaction conditions leads to assymmetrically or symmetrically substituted 2,4-bisamino- or 2,4-bisdialkylamino- and 2-alkylamino-4-dialkylamino-or 2-dialkylamino-4-alkylamino- or 2-amino-4-dialkylaminodihydrothiopyranylium iodides3, 4, 5, 6 resp. On treatment with alkali 4-alkylamino- and 4-dialkylamino-2-alkylaminothiopyranylium iodides3,4 are hydrolysed to the 2-alkylimino-2H-thiopyranes7. 4-Alkylamino-2-dialkylaminothiopyranylium iodides5 react with alkali to give three products: the two stereoisomeres 2-dialkylamino-4-alkylimino-4H-thiopyranes9 A,B and theN,N-substituted α,β,γ,δ-unsaturated thiocarboxamide10. The hydrolysis of 2,4-bisdialkylaminothiopyranylium iodide6 a leads to the 2-dialkylamino-4H-thiopyran-4-one11 a, the 4-dialkylamino-2H-thiopyrane-2-one12 and theN,N-substituted unsaturated thiocarboxamide10 d. α,β,γ,δ-unsaturated thiocarboxamides10 a-c are formed by the reaction of 2-amino-4-dialkylaminothiopyranylium iodides3 a-c with diluted alkali. By heating with acids10 a-c are cyclisized to the 2-aminothiopyranylium derivates3.     

Über die Bromierung von substituierten 3,4-Dihydro- und 6-Hydroxy- bzw. 6-Äthoxy-3,4,5,6-tetrahydro-2(1H)-pyrimidinonen

Bromination of 1-benzyl-4-methyl-3.4-dihydro-2(1H)-pyrimidinone (9 a) with 1 mole Br₂ in CHCl₃ yields 1-benzyl-5-bromo-6-hydroxy-4-methyltetrahydro-2(1H)-pyrimidinone,12 a, or the 6-ethoxypyrimidinone13 a, according to whether H₂O orEtOH is used in working up. With 2 moles Br₂,9 a analogously affords the 5.5-dibromopyrimidinnes14 a or15 a. Bromination of the 6-hydroxypyrimidinone10 a yields the same products,12 a and13 a, or14 a and15 a respectively, while the 4-phenyl-pyrimidinones9 b and11 b yield the corresponding 5-bromo-and 5.5-dibromopyrimidinones13 b and15 b. The structures of the compounds12 a-15 b are confirmed by their NMR data and chemical properties: the oxopyrimidinylmethylureas16 a and17 a are formed by the action of methylurea on12 a and13 a, or on14 a and15 a respectively; with hexamethylenetetramine,12 a reacts to give the 5.6-dihydroxypyrimidinone18 a, while13 b is transformed to the 4-phenylpyrimidinone19 b. 13 b was also synthesized from α-bromocinnamaldehyde. The mechanism of bromination is discussed.     

Zur Reaktion des Dihydro-6-methyl-4-phenyl-2(1H)-pyrimidinthions mit Formaldehyd und Aminen

Dihydro-6-methyl-4-phenyl-2(1H)-pyrimidinthione (1 a) reacts with formaldehyde and amines to 6-(2′-dialkylaminoethyliden)-tetrahydro-resp. 6-(2′-dialkylaminoethyliden)-tetrahydro-5-dialkylaminomethyl-2(1H)-pyrimidinthiones (2) as well as 6-alkyloctahydro-8a-ethoxy- resp. hydroxypyrido-[4,3-d]-pyrimidine-2(1H)-thiones (5).     

Über substituierte 2-Amino-3,4,5,6-tetrahydro-1H-pyrimidinium-und 1,2,3,4,6,7,8,9-Octahydropyrimido-[1,2—a]pyrimidiniumchloride

Crotonaldehyde resp. cinnamaldehyde react with guanidiniumchloride to give 2-amino-6-guanidinio-4-methyl-3.4.5.6-tetrahydro-1H-pyrimidiniumdichloride (4 a) resp. 6-hydroxy-4-phenylpyrimidiniumchloride3 b and the 4.6-dihydroxy-2.8-dimethyl (resp. 2.8-diphenyl)octahydropyrimido[1.2?a]pyrimidiniumchlorides6 a and6 b, resp. Action of 2.4-(or 2.6-)xylenol on4 a resp.3 b yields 2-amino-6-[2(or 4)-hydroxy-3.5-dimethylphenyl]-4-methyl-(resp. 4-phenyl)-3.4.5.6-tetrahydro-1H-pyrimidiniumchlorides (8 a resp.8 b or9 a resp.9 b), which are transformed to the zwitterionic compounds10 a–11 b by aqu. NaOH.6 a reacts with 2.4-xylenol to give the triazaoxabenzanthraceniumchlorid12 a·HCl (prove for the structure given for6 a). The chemical properties and the NMR-, UV-, mass- and IR-spectra of the compounds are discussed.     

Zur Chemie der 5-Alkylamino-4H-thiopyrano[2,3-b]pyridin-4-one

4-Alkylaminopyridinethiones · HCl (1 · HCl) react with bis-trichlorethylmalonate (3) predominantly to 5-alkylamino-4H-thiopyrano [2,3-b]pyridine-4-ones (6). With alcohols in the presence of acids at 25°C6 undergoes an alcoholysis to the corresponding alkyl-3-(2-thioxo-3-pyridyl)propionates (9). On heating in dilute alkali6 is hydrolysed via 4-alkylamino-2-thioxopyridyl-propylketones (11) to the tautomers, 4-hydroxy-2-thioxopyridylpropylketone (12 A) and 2-thioxo-3-(1-hydroxybutenyl)-4-piperidon (12 B), resp. On refluxing with alkali the ethyl-pyridylpropionate9 a is cyclisized to the 1-alkyl-1,6-naphthyridine-2(1H)-one (4 a), but boiling in ethanolic acid hydrolyses9 a via the pyridylpropionic acid10 to 4-alkyl-aminopyridylpropylketone (11 a). The latter can be transformed via the tautomers12 A,B and 2-methylthio-3-pyridylpropylketone (13) to the 4-hydroxy-3-butyrylpyridone (14 A) and its tautomer, 3-(1-hydroxy-butenyl)-piperidine-2,4-diones (14 B) resp. The structure of14 A,B is established by reaction of 4-isopropylamino-2(1H)-pyridone (2) with butanoylchloride to the 4-isopropylamino-3-butyrypyridone (15) and hydrolysis of15 to the tautomers14 A,B.     

Synthese von (5,10)-(7,8)-Bisepoxiden aus α- und β-4-Phenyl-1,2,4-triazolin-3,5-dion-Addukten von Vitamin D3 und Röntgenstrukturanalyse eines der Benzoylderivate

Oxidation of the α- and β-4-phenyl-1,2,4-triazolin-3,5-dione adducts of vitamin D₃ (2 and1) withMCPBA yields two diastereomeric mixtures of the (5,10)-(7,8)-dioxiranes3 a,3 b,3 c and4 a,4 b respectively. The corresponding benzoates5 a,5 b,6 a and6 b were prepared and the X-ray crystal structure of5 b was determined. This analysis proved5 b to be the (5R, 1 OS)-(7R, 8R)-dioxirane of the β-resp. (6S)-4-phenyl-1,2,4-triazolin-3,5-dione adduct1 of vitamin D₃.     

Über die Reaktionen von monosubstituierten Guanidinen mit 1-Phenyl-1,3-butandion

Methyl-, benzyl- and phenylguanidine (2 b–d) react with 1-phenyl-1,3-butanedione to yield exclusively N²-substituted 4-methyl-6-phenyl-2-pyrimidinamines10 b–d. The formation of isomeric N¹-substituted 2(1H)-pyrimidinimines11 or12 cannot be observed. The structural formulae of10 b and c were proved by spectroscopical methods. The structure of the phenylguanidine-phenylbutanedione-condensate was determined by comparison and establishment of the identity of its picrate with an authentical sample of10 d-picrate, which had been synthetized from pyrimidinthione13 (via methylthiopyrimidine16 · HI). Boiling13 with aniline in butanol yields thiodipyrimidine15 (and not10 d).     

Chinolizine und Indolizine,XIV Umlagerungen von Heterocyclen,X Ringumwandlungen von 1-Acyl-2-hydroxy-4-chinolizinonen

By heating with ammonia or aniline 1-acyl-2-hydroxy-4-quinolizinones (1 a–e) are transformed to 4-hydroxy-5-(2-pyridyl)-2-pyridones (3 a–f), with4 a–d as minor sideproducts. The structure of the rearranged compound3 f was established by an independent synthesis starting with6 and7. The reaction of1 a, d with ethyl β-aminocrotonate (β-ACE) yields pyrono-quinolizinones8 a, b and pyronopyridones9 a, b as byproducts; the latter are obtained in high yield by reaction of3 a, b with β-ACE. The ringtransformation reaction cannot be extended to 1-methoxycarbonyl-quinolizinones, such as10; in this case 2-amino-4-quinolizinone11 is the main product of the reaction with ammonia.     

Imidazo- und Diazino-Anellierungen an das [1]Benzothieno[2,3—d]pyrimidin-System

Derivatives of the following six ring systems were synthesized:

1. 3,10-Dihydro-[1]benzothieno[2,3-d]imidazo[1,5-a]-pyrimidine (I)
2. 6H-[1]Benzothieno[2,3-d]pyrazino[1,2-a]pyrimidine (II)
3. 1,5-Dihydro-[1]benzothieno[2,3-d]imidazo[1,2-a]-pyrimidine (III)
4. 6H-[1]Benzothieno[2,3-d]pyrimido[1,2-a]pyrimidine (IV)
5. 1,5-Dihydro-imidazo[1,2-a]thieno[2,3-d]pyrimidine (V)
6. 4H-Pyrimido[1,2-a]thieno[2,3-d]pyrimidine (VI)

The first four types are new heterocyclic systems. 2-Aminomethyl-5,6,7,8-tetrahydro-[1]benzothieno[2,3-d]pyrimidin-4(3H)-one (5), which was used as intermediate for typesI andII, was synthesized by various methods. TypesIII andIV were prepared from 2-methylthio-5,6,7,8-tetrahydro-[1]-benzothieno[2,3-d]pyrimidin-4(3H)-one via the corresponding 2-benzylamino derivatives, followed by ring closure.     

Chemie des 5,7-Dihydroxy-2H-thiopyrano[2,3-b]pyridin-4(3H)-ons

Hydrolysis of the 4-alkyliminothiopyrano[2,3-b]pyridinedioles (5) and 4-alkylaminothiopyrano[2,3-b]pyridones (6) resp. with 10% NaOH gives 5,7-dihydroxy-2H-thiopyrano[2,3-b]pyridine-4(3H)-one (7).7 can be obtained in better yield by reaction of 4-dimethylamino-2(1H)-pyridinethione (8) with bistrichlorphenylethylamlonate (2). Aminolysis of7 affords the two isomeric products5 and6. On treatment with hydrazines,7 reacts only to 4-hydrazonoderivatives5. By heating in bromobenzene5d is cyclisized to 1H-5,1,2,6-thiatriaza-acenaphthylen-7-ol (11). On methylation with methyljodide5,6 and7 furnish the 7-methoxyproducts13,14 and12. By heating in 20% NaOH7 is transformed into the 2-thioxo-3-pyridylmethylketone16 A and its tautomer, 2-mercapto-3-pyridylmethylketone16 B. The structures of5,6 and7 are discussed.     

Pyrindinchemie, 1. Mitt.: Über die Synthese des 3-Hydroxy-1-methyl-4-oxo-1,4-dihydropyrrolo[2′,3′:3,4]cyclopenta[1,2—b]pyridin-2-carbonsäureäthylesters (Ein Vertreter eines neuen heterocyclischen Ringsystems)

4 is synthesized starting from1 over the chloride3 and then cyclized byDieckmann condensation to the title compound8. The structure of4 is confirmed by chemical proof. By means of¹H-NMR-spectral analysis it could be determined that1 exists as internal salt (2a) of ethyl 5-hydroxy-7-oxo-7H-1-pyrindin-6-carboxylate.     

Über cyclische Guanidin—Mesityloxid- und Guanidin—Phoron-Kondensate

The basic product synthesized byTraube andSchwarz from mesityl oxide and guanidine has not been 4.4.6-trimethyl-4.5-dihydro-2-pyrimidinamine (1), but a mixture containing the 4.4.6-trimethyl-3.4-dihydro-2(1H)-pyrimidinimine (resp. an isomeric pyrimidinamine)2 a (resp.2 b, 2 c) and the dimeric 4.4′-methylenedi[2(1H)-pyrimidinimine] (resp. an isomeric methylenedipyrimidinamine)3 a (resp.3 b, 2 c) and the dimerisation reaction were studied in a series of experiments. The product of the reaction of guanidine and phorone is not the guanidinopropylpyrimidine8 ⁴, but the 4.4′-spirobi[2(1H)-pyrimidinimine] (resp. a spirobipyrimidinamine)11 a (resp.11 b, 11 c). No determination was possible on the basis of NMR whether the condensation products of guanidine—in solutions ofDMSO-d₆—are pyrimidinimines (2 a, 3 a, 11 a) or pyrimidinamines (2 b resp.2 c, 3 b resp.3 c, 11 b resp.11 c) or mixtures of the isomeric compounds. The NMR-and mass spectra of2 a (resp.2 b, 2 c),3 a (resp.3 b, 3 c),11 a (resp.11 b, 11 c) and their derivates are discussed.     

Stereochemie von α,ω-Diphenyl-alkan-α,ω-diolen

Reduction (both catalytically and with complex hydrides) of the diphenyl diketones1 (a, b, c andd withn=0, 2, 3 and 4) was investigated mainly with regard to the diastereomeric ratio of the diols2. For2 a and2 b exact results were obtained by NMR spectroscopy (without or with shift reagents) of the diol mixture (2 a) or after stereoselective cyclization to the cyclic ethers (3 b). AlsoGC andLLC were employed for the analysis of2 a (GC of the trimethylsilyl derivatives) and for the ethers3, resp. (GC for3 a and3 d;LLC for3 b and3 c). The reduction of1 a, 1 b (and in part1 c) proceeds with high stereoselectivity; themeso-diol preponderates in the case of2 a, therac.-diol for2 b and2 c; with increasingn the diastereomeric ratio approaches the statistical ratio of 1∶1. Preparations of the stereoisomeric diols (2 b, c andd via acetylenic precursors) and of the cyclic diphenyl ethers (by stereoselective cyclization and/or chromatographic separation;3 c and3 d for the first time) as well as the determination of their configurations are described. The latter was achieved by NMR and for the ethers3 also by hydrogenation of the corresponding heteroaromatics.     

Gezielte Konformationsänderungen an cyclischen Systemen, 2. Mitt.: Konformere 2-Phenyl-1,3-dithiane

In 2-phenyl-1.3-dithiane (1) and its p-methyl derivative (2) theequatorial phenyl adopts a conformation coinciding with the symmetry plane of the molecule. For 2-(2′-methylphenyl)-1.3-dithiane (4) acisoid relation of theaxial hydrogen on C-2 and the aromatic methyl group was established. This conformation can be changed by substitution of position 2 by methyl: in this geminally substituted compound (3), phenyl no longer assumes theequatorial position, and the plane of the phenyl group isperpendicular to the symmetry plane of the molecule. These deductions depend on the deshielding effect of sulphur and the diamagnetic anisotropy of the aromatic ring in the NMR spectra influencing the chemical shifts of the orthoprotons and of the protons of the dithiane ring respectively. The influence of the conformation on both of these effects is taken into account.     

Pd(0) catalyzed three-five-component C-2-arylallylation of active methylene heterocycles: pyrazolones, oxazolones, isoxazolones and N,N′-dimethylbarbituric acid

A Pd(0) catalyzed three-five-component cascade involving an aryl iodide, allene and a heterocyclic pronucleophile is used to prepare 2-arylallyl derivatives (10-12 and 16-24) from 3-phenyl-5-isoxazolone (6) and 1-phenyl-3-methylpyrazolin-5-one (7) in moderate yield. Similar cascade allylation of masked amino acids 4-methyl-2-phenyl-4H-oxazol-5-one (8a), 4-benzyl-2-phenyl-4H-oxazol-5-one (8b) and 4-isopropyl-2-phenyl-4H-oxazol-5-one (8c) gave analogous products (25-37) in good yield. N,N-Dimethylbarbiturates (38-49) are similarly prepared from N,N-dimethylbarbituric acid (9) in excellent yield.     

Zur Kenntnis der Substitutionsprodukte der (2H)-Imidazol-4(3H)-thione und 2H-Imidazol-4(3H)-one

2H-Imidazole-4(3H)-thiones (a), available from methyl alkyl and methyl aryl ketones with sulfur and ammonia, react via their corresponding N-sodium compounds or in presence of tert. amines with alkyl and aryl carboxylic acid chlorides to give the corresponding intensely coloured (orange to violett) cryst. 3-acyl-2H-imidazole-4(3H)-thiones4 a-q and6–26. With dicarboxylic acid dichlorides the colourless cryst. N,N′-diacyl-bis-3-imidazoline-5-thiones5 a-d and27–32 are obtained. With carbamic acid chlorides and chloroformic acid esters the corresponding urea (33–35) and urethane derivatives36, 37 are formed. In an analogous way 2H-imidazol-4(3H)-ones react with acid chlorides to 3-acyl-2-imidazol-4(3H)-ones (44–50), which can also be obtained by treating the corresponding 3-acyl-2H-imidazole-4(3H)-thione with KMnO₄.     

7,15-Diazadispiro[5.1.5.3]hexadecan und Derivate, 1. Mitt.: Darstellung der Grundkörper

As starting materials for theoretical and pharmacological studies 7,15-diazadispiro[5.1.5.3]hexadecane (1), its 14-imino-(2) and 14-oxo-derivative (3) were prepared. Reduction of bis-(1-cyanocyclohexyl)-amine (4) withLAH leads to a mixture of1 and2. For the exclusive preparation of1, 4 is treated with conc. H₂SO₄ to yield the corresponding 14,16-dioxohexadecane, which is reduced to1 withLAH. The preparation of3 is effected by acid hydrolysis of acetylated2.     

Anion-directed organized assemblies of protonated pyrazole-based ionic salts

The reactions of 3(5)-(4-methoxyphenyl)-5(3)-phenyl-1H-pyrazole (L ¹ ) with nitric acid and 5-(4-benzyloxyphenyl)-3-(furan-2-yl)-1H-pyrazole(L ² ) with hydrochloric acid produced [HL ¹ · NO₃] (Salt-1) and [HL ² · Cl] (Salt-2). The structures of Salt-1 and Salt-2 were determined by single crystal X-diffraction. In Salt-1, HL ¹ showed [2 + 2] binding of NO₃ ^? ions in the solid state to form dimer architecture with R ₁ ² (4) and R ₄ ⁴ (14) graph sets. An anion directed one-dimensional anion-assisted helical chain with active participation of the chloride ion and protonated pyrazole via N–H···Cl hydrogen bonding in Salt-2. In addition, the protonated HL ² molecules interacted with each other through weak C–H···π interactions resulting in the formation of another one-dimensional helical chain.     

Über die Reaktionen von 2-Cyclohexenonen mit Ammoniumthiocyanat bzw. Thioharnstoff Über Heterocyclen, 59. Mitteilung

The 2-cyclohexenones1 a, b andc react with NH₄SCN to give 3,5,5-trimethyl-, 3-methyl-5-phenyl- and 3-methyl-2-cyclohexeniminiumthiocyanates8 a, b andc resp. (i.e. salts of α,β-unsaturated imines) and not the expected diazabicyclononane-thiones5 a, b andc. Alternative formulae for the1—NH₄SCN-condensates are discussed and rejected on the basis of IR- and NMR-spectra and the chemical properties of5 a-c. By action of thiourea inMeOH/NaOMe the 2-cyclohexenones1a, d ande are transformed into 1-hydroxy-5,7,7-trimethyl-, 1-hydroxy-5-methyl- and 1-hydroxy-2,4-diazabicyclo[3.3.1]nonane-3-thiones5 a, d ande resp. The structure of the diazabicyclononane-thiones5 a, d ande is established by means of NMR-, IR- and MS-spectra. 8 a-c and5 e showed no significant herbicidal and only small fungicidal (8 b, c) and insecticidal (8 a-c) activities in screening tests.     

Preparation, reactivity and tautomeric preferences of novel (1H-quinolin-2-ylidene)propan-2-ones

1,1-Difluoro-3-(1H-quinolin-2-ylidene)propan-2-one 1a, 1,1,1-trifluoro-3-(1H-quinolin-2-ylidene)propan-2-one 1b, 1,1,1-trifluoro-3-(4-chloro-1H-quinolin-2-ylidene)propan-2-one 1c and 1,3-dibromo-1,1-difluoro-3-(2-quinolyl)propan-2-one 2 are prepared and characterized by various spectroscopic techniques. The crystal structure of 1a is determined by X-ray diffraction. Furthermore, a series of previously known non-halogenated (1H-quinolin-2-ylidene)propan-2-ones 1d-1h are oxidized with AgBrO₃ in the presence of AlCl₃. In all cases, 2-(1-bromo-1-chloromethyl)quinoline 3 is obtained in high yield. The bromination order and sites of 1a are analyzed based on ab initio MP2 and DFT calculations for the molecule and its anions.