Synthese und Reaktivität von 2- und 3-hydroxylierten Dihydro-1,4-Benzoxazinen

2 can be pyrrolized to yield3 a, which in turn may be hydrolyzed with HCl to3 b. Acetylation of3 a followed by a reaction with trifluoroacetic acid (TFA) gives3 e. Elimination of ethanol from3 a or of water from3 e is not possible. Treatment of1 a with pyridine/acetic anhydride andTFA or with acetic acid/acetic anhydride affords4 a and4 b, resp. Reaction of4 b in benzene/p-toluenesulfonic acid for 2 hours yields both ethers5I and5II, whereas after 6 hours 4-acetyl-4H-1,4-benzoxazine (6) is obtained. The structures of all products are established by chemical and spectroscopic methods.

Teile aus der DissertationW. Kropp, Universität Wien, 1977.     

Synthesen und Eigenschaften ethinylierter und trimethylsilylethinylierter Molekülsysteme mit 1,6-Methano[10]annulen-Partialstruktur

2-Trimethylsilylethinylated 1,6-methano[10]annulene1 a was obtained by reaction of 2-bromo-1,6-methano[10]annulene with trimethylsilylacetylene in the presence of bis-(triphenylphosphin-)-Pd (II) chloride and Cu(I) and also by reaction of 1,1-diiodo-2-(1,6-methano[10]annulene-2-yl)-ethene (2) withn-buthyl-lithium followed by hydrolysis.1 a reacts with 2N NaOH to 2-ethinyl-1,6-methano[10]annulene (1 b). 2,7- and 2,10-dibromo-1,6-methano[10]annulene can be substituted to give the trimethylsilylethinylated compounds3 a–6 a, which then can be transformed with 2N NaOH into the desilylated products3 b–5 b.

Wolfgang Kraus, Stuttgart-Hohenheim, mit den besten Wünschen in Freundschaft zum 60. Geburtstag gewidmet     

Synthese des 4-Hydroxy-6,6-dimethyl-5,6-dihydro-2H-thiopyran-2-thions bzw. -ons und der entsprechenden Tautomeren

The tautomers 4-hydroxy-6,6-dimethyl-5,6-dihydro-2H-thiopyran-2-thione (4 a) and 2-mercapto-6,6-dimethyl-5,6-dihydro-4H-thiopyran-4-one (4 b) resp. were synthesized by hydrolysis of 4-amino-5,6-dihydro-2H-thiopyranthiones6,8. On methylation of4 a,b only the S-methyl product7 is formed. Hydrolysis of 4-amino-2-methylthiothiopyranyliden iodides11 leads—depending on the amino group of11—either to the thiopyranone7 or to the 4-imino-thiopyranes12 and to -amino-,,,-unsaturated-methyldithio carboxylates13. On reaction of4 a,b with hydrogenperoxyd the tautomers 4-hydroxy-5,6-dihydro-2H-thiopyran-2-one5 a and 5,6-dihydro-2H-thiopyran-2,4(3H)diones5 b resp. are formed.4 a,b and5 a,b undergo an aminolysis with prim. and sec. amines to the corresponding 4-amino-2H-thiopyran-2-thiones6,8 and -ones10 resp. On heating in alcohols the 4-alkoxy-thiopyrane-2-thiones and -ones9,14 are formed from4 a,b and5 a,b resp.

     

Synthese neuer 4-Hydroxybenzonitrilderivate und deren herbizide Eigenschaften

The synthesis of several new derivatives of 2-amino-4-hydroxybenzonitrile2 and their herbicidal screening data are described. Thus, halogenation and furtherSandmeyer-Reaction of2 leads to the 2,3,5-trihalogenated derivatives5 a–e. Reaction of ethyl chloroformate with the amino group of2 gives6 a, acylation7 a, b and8. The 3,5-dihalogenated compounds10 a–e are obtained from6 a and7 a, b by bromination or iodation. The hydroxyl group of6 a, 7 a, b and10 a, c, e reacts with N,N-disubstituted carbamyl chlorides to give6 c, d, 9 a, b, 11, 12 and13 a, b.

     

Synthese von 1-Ary1-4-methylthio-2-azetidinonen

TheN-arylthioformimidates4 a-e, which may be obtained byS-alkylation of the thioformanilides3 a-e, react with chloroacetylchloride/triethylamine to yield the (3R,4S/3S,4R)-1-aryl-3-chloro-4-methylthio-2-azetidinones5 a-e and the formanilides6 a-e. Dehalogenation of5 b-e with tri-n-butyltinhydride yield the title compounds7 b-e. Hydrogenolysis of7 b and7 c yields7 f and7 g.

     

Synthesen mit Nitrilen,LXXV Zur Reaktivität der Dimeren von Malononitril und Cyanessigester gegenüber Dimethylformamid-dimethylacetal

Reaction of malononitrile dimer (1) and the codimer from cyanoacetate and malononitrile (2) with dimethylformamide-dimethylacetal (DMFDMA) leads to the monocondensation products5 a, b. The isomeric codimer3, however, gives the amidine6. Ring closure reactions of5 a with ammonia and primary aliphatic and aromatic amines yield 2,4-diamino-3,5-pyridinedicarbonitriles7 a–j, in the case of5 b the 4-amino-1,2-dihydro-2-oxo-3,5-pyridinedicarbonitriles8 b–i. Reactions of1 and2 with an excess ofDMFDMA give the biscondensation products11 a, 11 b.11 b reacts with primary aromatic amines to give the pyridine derivatives13. The structure of13 was confirmed by hydrolytical cleavage to the dicyano-aminopyridone14. Treatment of13 with concentrated hydrochloric acid leads to the pyridopyrimidine derivatives15.

     

Aromatische Spirane. 15. Mitt. Darstellung von 2,2′-Spirobi-(s-hydrindacen)-1,1′-dion und von 4,4′-disubstituierten 2,2′-Spirobi-(s-hydrindacenen)

The title compound6 a was prepared by cyclisation of the diacid4 b. The diester4 a of4 b was synthesized by alkylation of2 with3 and following Retro-Claisen-reaction. After catalytic reduction of6 a to8 a two identical substituents were introduced byFriedel-Crafts-reaction (28). By transformation of the acetylgroups several other derivates (29–36) could be obtained. The unsymmetrical compounds (e.g.21) were prepared from20, whose precurser was the spiroketon10 a.

     

Die Reaktion von Naphth[1,2-d]indolen mit Natrium in Äthanol

The reactivity of naphth[1,2-d]indoles1a, 3a and6 towards sodium in ethanol was studied.1a yields2, 3a the nor-product3b and dihydrothebainone-dihydromethine (4). Bt reaction of6, octahydrophenanthrenes7a and7b are obtained, the structures of which were elucidated byHofmann degradation to8a and8b.     

Syntheses with pyridinium and sulfonium salts of acylated β-enaminonitriles

Summary Pyridinium and sulfonium salts2a–e which can be prepared from 3-amino-2-(-haloacetyl)-crotonitriles and 3-amino-2-(-halo-acetyl)-3-phenyl-acrylonitriles react with malononitrile in the presence of a base to 3-amino-2-pyridinio-phenolates3a,b and 3-amino-2-sulfonio-phenolates3c–e. In an analogous way, 3-amino-2-(diethyloxyphosphoryl)-phenol5a and 3-amino-2-(p-tolyl-sulfonyl)-phenol5b have been prepared. 2,3-Diamino-phenoles6a,b are formed from the pyridinium salts3a,b. The behaviour of the pyridinium salts2a,b towards heterocumulenes has been investigated. Cyanamide leads to the (2-amino-4-hydroxy-pyrid-3-yl)-pyridinium salt8c. Phenylisothiocyanate gives the 3-pyridinio-2-thioxo-pyridin-4-olates9a,b. Carbon disulfide gives rise to 3-pyridinio-2-thioxo-pyridin-4-olate10 or 3-pyridinio-2-thioxo-thiopyran-4-olate11, depending on the substituent at the 6-position. Phenylisocyanate reacts to the pyrimidin-2,4-dione12 with loss of N-methyl-pyridinium chloride. S-methylation of9a and cleavage of the pyridine moiety yields the 3-amino-2-methylthio-pyrid-4-one14. The structures were investigated by¹H and¹³C NMR spectroscopy.

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Synthesen mit Pyridinium- und Sulfoniumsalzen von acetylierten -Enaminonitrilen

Zusammenfassung Pyridinium- und Sulfoniumsalze2a–e, die aus 3-Amino-2-(-halo-acetyl)-crotonsäurenitril und 3-Amino-2-(-halo-acetyl)-zimtsäurenitril hergestellt werden können, reagieren mit Malonsäuredinitril in Gegenwart einer Base zu 3-Amino-2-pyridinio-phenolaten3a,b und 3-Amino-2-sulfonio-phenolaten3c–e. In Analogie wurden 3-Amino-2-(diethyloxyphosphoryl)-phenol5a und 3-Amino-2-(p-tolyl-sulfonyl)-phenol5b erhalten. 2,3-Diamino-phenole6a,b werden aus den Pyridiniumsalzen3a,b gebildet. Das Verhalten der Pyridiniumsalze2a,b gegenüber Heterokumulenen ist untersucht worden. Cyanamid führt zum (2-Amino-4-hydroxy-pyrid-3-yl)-pyridiniumsalz8c. Phenylisothiocyanat liefert die 3-Pyridinio-2-thioxo-pyridin-4-olate9a,b. In Abhängigkeit vom Substituenten in der Position 6 entsteht bei der Reaktion mit Schwefelkohlenstoff ein 3-Pyridinio-2-thioxo-pyridin-4-olat10 oder ein 3-Pyridinio-2-thioxo-thiopyran-4-olat11. Phenylisocyanat reagiert zum Pyrimidin-2,4-dion12 unter Verlust von N-Methyl-pyridiniumchlorid. S-Methylierung von9a und Spaltung des Pyridiniumringes ergibt das 3-Amino-2-methylthio-pyrid-4-on14. Die Verbindungen wurden¹H- und¹³C-NMR-spektroskopisch untersucht.

     

Basische Tetrahydro-dibenzofuran-Derivate mit einem Abstand von drei C-Atomen zwischen dem Stickstoff und dem quartären C-Atom

Pummerer's ketone (1) is a pharmacophoric synthon, which can be used for a great number of synthetic variations. We have investigated the insertion of basic groups into C-1, C-2 and C-3. TheClaisen rearrangement of the allylic alcohols2 a and2 b leads to3 a and3 b, the reduction of which produces4 a and4 b. TheMannich reaction of1 unexpectedly gives the 2-aminoalkylcompounds7 c-j and the synthesis of the derivatives2e-j was performed by aminolysis of the 3-chloro-compound2 d.     

2-Amino-1-cyan-glutaconsäureamid-1-methylester,ein Dimeres des Cyanessigesters und Cyanacetamid

Synthesis of methyl 3-amino-4-carbomyl-2-cyano-2-butenoate is described and2 a classified as a dimer of methyl cyanoacetate and cyanoacetamide. By ammonolysis of the dimer of methyl cyanoacetate with dimethylamine and anilines, resp. the dimethylamide and anilides, resp. (2 b and3 a–j) are obtained. Condensation with salicylaldehyde to the pyrone derivative4 proves the structure of2 a, ring closure reactions in basic or acidic medium yield the pyridones6 a and7 a,b, coupling with diazonium salts the pyridazines8 a–d. The amides2 and the anilides3 show hindered rotation of the enamino- and the amide-group by hydrogen bonds between the nitrogen functions and the ester carbonyl (Z-form). The G values are reported.

     

Zur gezielten Oxidation der Δ7-Doppelbindung in den 4-Phenyl-1,2,4-triazolin-3,5-dion-Addukten des Vitamin D3

The possibility of regio- and stereospecific oxidation of the 7-double bond of the 4-phenyl-1,2,4-triazolin-3,5-dione adducts1 a and1 b of Vitamin D₃ is reported. Oxidation of the corresponding benzoates2 a and2 b withm-Chlorperbenzoic acid yields the two oxirans3 a and3 b which in turn with NaI-CH₃COOH-Zn after saponification to5 a and5 b lead to the allylic alcohols6 a and6 b.

     

Beiträge zur Chemie von Pyrazolyalkinen

Palladium-catalyzed reactions of 1-benzoyl-4-iodopyrazole (2a) with monosubstituted acetylenes3a,3b and3c in triethylamine solution provide convenient access to the cross-coupled products4a,4b and4c. The 4-ethinylpyrazoles5a and7 obtained after methanolytic removal of the protecting groups are transformed conveniently into the ketones6a and8 by means of Hg(II)-mediated hydratation.

     

Ozonolyse von Olefinen,III: Säurekatalysierte Ozonolyse von 3-Hexen-1,6-und 2-Penten-1,5-dicarbonylderivaten

Summary The ozonolysis of mono-unsaturated compounds containing the structural element =CH-CH₂-R [R=COOH, COOCH₃, CH(OCH₃)₂] was investigated. Reductive ozonolysis of (E)-3-hexene-1,6-dioic acid gives methyl 3,3-dimethoxypropanoate (2), whereas ozonolysis of dimethyl (E)-3-hexene-1,6-dioate (1a) and (Z)-1,1,6,6-tetramethoxy-3-hexene (1b) in a methanolic solution of HCl leads to a mixture of2, dimethyl malonate (3 a) and 1,1,3,3-tetramethoxypropane (3 b). The homologuos derivatives, dimethyl glutaconate (4 a) and 1,1,5,5-tetramethoxy-2-pentene (4 b), were ozonized to give mixtures of2, 3, dimethyl oxalate (5), methyl 2,2-dimethoxyacetate (6 a), and 1,1,2,2-tetramethoxyethane (6 b). The ratios of the various reaction products were determined by gas chromatography. In each case the formation of the bifunctional derivatives2 and6 a was favoured.

     

Synthesis of some schiff bases of 3-aroyl-6-aryl-4-hydroxy-2H-pyran-2-ones

Summary The reaction of 3-aroyl-6-aryl-4-hydroxy-2H-pyran-2-ones (Ar=p-tolyl, 1,1-biphenyl-4-yl or thienyl) with aniline and substitutedo-phenylenediamine (R=H, CH₃ or Cl) yields a series of new Schiff bases2a–f in 51–72% yield. Bromination of1a gave the 5-bromo derivative1c, while the compounds1a,1b,2b,2e, and2f were converted into 2,6-diaryl-4H-pyran-4-ones3a–c. All products have been fully characterized.

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Synthese von Schiff'schen Basen von 3-Aroyl-6-aryl-4-hydroxy-2H-pyran-2-onen

Zusammenfassung Die Reaktion von 3-Aroyl-6-aryl-4-hydroxy-2H-pyran-2-onen (Ar=p-Tolyl, 1,1-Biphenyl-4-yl oder Thienyl) mit Anilin und substituierteno-Phenylendiaminen liefert neue Schiff'sche Basen2a–f/bd in 51–72% Ausbeute. Bromierung von1a gab das 5-Bromderivate1c, während die Verbindungen1a,1b,2b,2e und2f in 2,6-Diaryl-4H-pyran-4-onen3a–c übergeführt wurden. Alle Produkte wurden voll charakterisiert.

     

The reaction of 4-methoxycoumarins with prenyl bromide: Synthesis of 4′,4′,5′-trimethyl-dihydrofurano-coumarins and 2,2-dimethyl-chromenopyrans

The reaction of 7-hydroxy-4-methoxy- (1a), 7-hydroxy-4,5-dimethoxy-(1b) and 5-hydroxy-4,7-dimethoxy (1c) -2H-1-benzopyran-2-ones with prenyl bromide in acetone in the presence of anhydrous potassium carbonate gave the corresponding prenyloxycoumarins1d,1e, and1f. The prenyloxy coumarins1d,1e,1f onClaisen migration by refluxing inN,N-dimethyl aniline gave the corresponding 4,4,5-trimethyl-dihydrofuranocoumarins2a,2b, and3. However, the reaction of1a,1b, and1c with 3-chloro-3-methyl-but-1-yne in acetone in presence of potassium carbonate and potassium iodide gave the corresponding propargyl ethers1g,1h,1i, which on refluxing inN,N-dimethyl aniline gave the corresponding 2,2-dimethylchromenopyrans4a,4b, and5. These can also be obtained directly if the reaction is carried out in the presence of dioxan.

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Die Reaktion von 4-Methoxycumarinen mit Prenylbromid: Synthese von 4,4,5-Trimethyl-dihydro-furanocumarinen und 2,2-Dimethylchromenopyranen

Zusammenfassung Die Reaktion von 7-Hydroxy-4-methoxy-(1a), 7-Hydroxy-4,5-dimethoxy-(1b) und 5-Hydroxy-4,7-dimethoxy-2H-1-benzopyran-2-onen (1c) mit Prenylbromid in Aceton in der Gegenwart von wasserfreiem Kaliumcarbonat ergab die entsprechenden Prenylcumarine1d,1e und1f. Diese ergaben durchClaisen-Wanderung bei Rückfluß inN,N-Dimethylanilin die entsprechenden 4,4,5-Trimethyldihydrofuranocumarine2a,2b und3. Die Reaktion von1a,1b und1c mit 3-Chlor-3-methyl-1-butin in Aceton in Gegenwart von wasserfreiem Kaliumcarbonat und Kaliumjodid ergab die entsprechenden Propargylether1g,1h und1i, die ihrerseits bei Rückfluß inN,N-Dimethylanilin die jeweiligen 2,2-Dimethylchromenopyrane4a,4b und5 ergaben. Letztere können auch direkt erhalten werden, wenn die Reaktion in Gegenwart von Dioxan durchgeführt wird.

     

3-Methyl[1,3,4]thiadiazino[2,3-b]quinazolin-6-ones

4H,6H-[1,3,4]Thiadiazino[2,3-b]quinazolin-6-one with a methyl group in position 3 (6a) has been synthesised by the condensation of 3-amino-2-mercapto-3H-quinazolin-4-one (1) with allyl bromide (2) followed by treatment with bromine and subsequent dehydrohalogenation of the brominated product (4) with ethanolic sodium hydroxide. Its isomeric 3-methyl-2H,6H-[1,3,4]thiadiazino[2,3-b]quinazolin-6-one (6b) has also been obtained by condensation of1 and bromoacetone (7) followed by cyclisation of the intermediates (8 or9) with hydrobromic acid or with concentrated sulphuric acid. The structures have been established on the basis of IR and PMR data.

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3-Methyl[1,3,4]thiadiazino[2,3-b]chinazolin-6-one

Zusammenfassung Zur Synthese von 4H,6H-[1,3,4]thiadiazino[2,3-b]chinazolin-6-on (6a) wurde die Kondensation von 3-Amino-2-mercapto-3H-chinazolin-4-on (1) mit Allylbromid mit nachfolgender Behandlung mit Brom und Dehydrohalogenierung des bromierten Produktes4 mit ethanolischer Natronlauge herangezogen. Das zu6a isomere 2H,6H-Produkt6b wurde ebenfalls durch Kondensation von1 mit Bromaceton und nachfolgender Cyclisierung der Zwischenprodukte8 bzw.9 mit HBr oder H₂SO₄ erhalten. Die Strukturen wurden mittels IR und NMR abgesichert.

     

Über Reaktionen mit Betain, 13. Mitt.: Darstellung von trihalogenacetyl-methyliden und ihrer Salze aus Betainen

Reaction of the betaine1 and pyridinebetaine8 with trifluoroacetic anhydride yields the salts4a or9a and the yellow ylide5, respectively. In an analogous manner8 reacts with trichloroacetic anhydride to give11a. In a competitive reaction the trifluoroacetates6 and10 are also formed. Pyridinebetaine hydrochloride reacts similarily with trichloroacetic anhydride.

12. Mitt.:Wittmann H., Sobhi D., Petio F. A., Z. Naturf.31 b, 850 (1976).     

Untersuchungen über die Bildung von 2-Acylcyclopentanonen aus 1-(1-Äthynyl)-cyclopentenen und Perameisensäure

The reaction of1 a with H₂O₂ in HCOOH yielded 37%4 a and 15%3 a. 1 c reacted under similar conditions to4 c (29%),3 b (12%) and3 c (22%).1 b was less reactive towards H₂O₂ in HCOOH due to its low solubility in HCOOH;4 b was isolated with 6% yield, 69%1 b remained unchanged.Under conditions of epoxide hydrolysis and catalysis of theRupe rearrangement, the epoxides2 a and2 b yielded 37%4 a and 30%4 b, resp.Based upon these experimental results, mechanisms for the observed reactions are proposed.     

Über kondensierte Heterocyclen aus β-Isothiocyanatoketonen und Aminoalkoholen bzw. Diaminen

2- and 3-aminoalcohols, o-aminobenzylalcohol, o-hydroxybenzylamine and o-amino(thio)-phenol react with 4-isothiocyanato-4-methyl-2-pentanone (1) to yield derivatives of condensed heterocycles (oxazolopyrimidines7, pyrimidooxazine8, pyrimidobenzoxazines9, 10, pyrimidobenzoxazole11 a and pyrimidobenzothiazole11 c respectively). Ethylenediamine or 1,3-diaminopropane react with1 to yield either imidazo-pyrimidine13 and pyrimidopyrimidine14 respectively or the 1,2-ethylene- and trimethylenebisdihydro-2(1H)-pyrimidinethione15 a, b respectively, according to the molar ratio of the reactants. o-Phenylenediamine gives pyrimidobenzimidazole11 d. 11a undergoes ring cleavage in boiling dimethylformamide followed by methylpyrimidine-pyridine rearrangement to dihydrohydroxyphenylamino-2(1H)-pyridinethione12, while15 a is converted into the bis-4-(ethanediimino)-pyridinthione16.