Synthese von 3,3a-Dihydro-2H,5H-azeto[2,1-b]benzo[d]1,3-oxazin-2,5-dionen, 2. Mitt.

Starting from the thioformimidates4 a, b, c and substituted acetylchlorides, the 3R*/4S* 4-methylthio-2-azetidinones5, 13 a, b, c are synthesized.5 is dehalogenated to6. Debenzylation of6 leads to7 and10, which undergo ring closure to9 and12 by the action of chlorine inDME. Hydrazinolysis of13 a, b, c and acylation of the intermediates14 a, b, c afford15 a, b, c. Removal of the protective groups leads to16 d, e, f. The diastereomeric mixtures17 d, e, f, which are obtained by the chlorolysis of16 d, e, f, undergo ring closure to the 3R*/4S* isomers of the title compounds18 d, e, f either spontaneously or by action of silvertetrafluoroborate/silveroxide. Chlorolysis of19 yields the diastereomeric mixture20. Treatment of20 with silvertetrafluoroborate/silveroxide gives21 and22.

Herrn Professor Dr.Hermann Bretschneider zum 80. Geburtstag gewidmet.     

Synthese von 3,3a-Dihydro-2H,5H-azeto[2,1-b]benzo[d]-1,3-oxazin-2,5-dionen,I

The thioformimidates4, which may be obtained by S-alkylation of the thioformamides3, react with chloroacetylchloride/triethylamine to yield the (3R, 4S/3S, 4R)-3-chloro-4-methylthio-2-azetidinones5. Dehalogenation of5 leads to6, which undergoes ring closure by the action of mercuric oxide. Treatment of8, which may be synthesized by chlorolysis of7, with triethylamine gives also the title compounds9.

     

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.     

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.

---

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.

     

Über Darstellung und Reaktivität von 2,4-Diazabicyclo[3.3.1]nonan-3-onen

The 2-cyclohexenones1 a andd resp. react with urea in HCl/EtOH to give 1-hydroxy-4-methyl-7-phenyl- and 1-hydroxy-2,4-diazabicyclo[3.3.1]nonane-3-ones3a and3d resp., whereas the 2-cyclohexenones1b andc resp. transformed by urea to 1,7-dimethyl- and 1-methyl-4-ureido-2,4-diazabicyclo[3.3.1]nonan-3-ones9b andc resp. In the condensation of isophorone1e with urea a product C₁₃H₂₈N₈O₄ of indisdinct structure was formed, whereas the bicyclus3e could not be isolated.Reaction ofAcOAc with3a yielded the 5-methyl-3-oxo-7-phenyl-2,4-diazabicyclo[3.3.1]non-1-ylacetate (15); on heating of3a with acids decomposition to1a and urea took place. NoWagner-Meerwein-rearrangement was observed. The MS-spectra of3a andd are discussed; NMR- and IR-data are reported.No significant herbicidal, fungicidal or insecticidal activity was found in screening-tests on3a.

     

Pyrido[2,3-d]pyrimidines,II. One step synthesis of pyrido[2,3-d]pyrimidines and pyrimido[4,5-b]quinolines from 6-amino uracils

Summary Reduction of 6-azidouracils2 with hydrogen palladium or sodium dithionite afforded the corresponding 6-aminouracils5 which could also be obtained by reaction of2 with triphenylphosphanevia phosphazenes and subsequent hydrolysis (Staudinger reaction). The use of trimethylphosphite instead of phosphanes yields with2b the expected trimethoxyphosphazene3c, whereas2a reacts to the phosphonoaminopyrimidine4. The syntheses of 5-hydroxy pyrido[2,3-d]pryimidine-2,4,7-triones6, pyrido[2,3-d]pyrimidine-2,4,5-triones8, cyclopenta[e]pyrido[2,3-d]pyrimidin-2,4,5-triones7a,c, and tetrahydro-pyrimido[4,5-b]quinolin-2,4,5-triones7b,d by condensation of 6-aminouracils5 with malonates, ethylaceto/benzoylacetate, ethyl 2-oxocyclopentanecarboxylate and ethyl 2-oxocyclohexanecarboxylate, respectively, are described.

---

Pyrido[2,3-d]pyrimidine, 2. Mitt. Einstufige Synthese von Pyrido[2,3-d]pyrimidinen und Pyrimido[4,5-b]chinolinen aus 6-Aminouracilen

Zusammenfassung Reduktion der 6-Azidouracile2 mit Wasserstoff/Palladium oder Natriumdithionit ergibt die entsprechenden 6-Aminouracile5, die auch durch Reaktion von2 mit Triphenylphosphin und anschließende Hydrolyse erhalten werden können (Staudinger-Reaktion). Die Verwendung von Trimethylphosphit anstelle von von Trimethylphosphin ergibt mit2b das erwartete Trimethoxyphosphazin3c, während2a zum Phosphonoaminopyrimidin4 reagiert. Die Synthesen der 5-Hydroxy-pyrido[2,3-d]pyrimidin-2,4,7-trione6, der Pyrido[2,3-d]pyrimidin-2,4,5-trione8, der Cyclopenta[e]pyrido[2,3-d]pyrimidin-2,4,5-trione7a,c und der Tetrahydro-pyrimido[4,5-b]chinolin-2,4,5-trione7b,d durch Kondensation der 6-Aminouracile5 mit Malonat, Acetat, Ethyl-2-oxocyclopentancarboxylat und Ethylcyclohexancarboxylat werden beschrieben.

     

Strukturelle Abwandlungen an partiell silylierten Kohlenhydraten mittels Triphenylphosphan-Azodicarbonsäureester, 5. Mitt.: Transformationen an Glykonolactonen

Reaction ofD-glucono-1,5-lactone1 with two equivalents oft-butyldimethylchlorosilane yields via a ringcontraction 2,6-bis-O-(t-BDMSi)-D-glucono-1,4-lactone2a as main product and a small amount of 5,6-bis-O-(t-BDMSi)-D-glucono-1,4-lactone2c. Under the same conditionsL-mannono-1,4-lactone3 is transformed to the derivatives 2,6-bis-O-(t-BDMSi)-L-mannono-1,4-lactone3a and 3,6-bis-O-(t-BDMSi)-L-mannono-1,4-lactone3c as the minor product. 2,6-bis-O-(t-BDMSi)-D-galactono-1,4-lactone4a and 2,6-bis-O-(t-BDMSi)-D-gulono-1,4-lactone5a are also prepared from the corresponding glyconolactones4 and5. Whereas the compounds2a, 2c, 4a and5a withAc ₂O-pyridine give the bisacetylderivatives2b, 2d, 4b and5b, 3c is converted by an accompanying migration of one silylgroup to the 5,6-bis-O-(t-BDMSi)-2,3-bis-O-acetyl-L-mannono-1,4-lactone3d. The gluconolactone derivative2a reacts easily withTPP/DEAD/HX to the 5-X-L-idono-1,4-lactone derivatives6a (X=N₃),6b (X=p-NO₂-C₆H₄COO) and6c (3-O-acetylderivative of6a). Treating6b with a second equivalentTPP/DEAD/HX leads to the unsaturated sugarlacton7b. Without an external nucleophile2a affords withTPP the mixture of 2,6-bis-O-(t-BDMSi)-3,5-carbonato-D-glucono-1,4-lactone2c, 3,5-anhydro-L-idono-1,4-lactone8 and 3,6-anhydro-D-glucono-1,4-lactone9. Analogous procedures applied to4a yield theL-altronolactonoderivatives10a, 10b and10c, the unsaturated sugarlactone11b on the one and the 3,5-carbonatogalactonolactone4c and the 2,6-bis-O-(t-BDMSi)-3-desoxy-5-ethoxycarbonyl-D-threo-hex-2-en-1,4-lactone12 on the other hand.Whereas the bis-silyletherderivative3a is transformed by the title system exclusively by an elimination process to13, the derivative5a affords withTPP/DEAD without any elimination the 3,6-anhydrosugar14. Partial desilylation of14 followed by acetylation gives the derivatives14a and14b.Structural elucidations were achieved by¹H-NMR-analysis. In some cases also CD-measurements allowed suitable correlations.

Mark, E., Zbiral, E., Brandstetter, H. H., 4. Mitt., Mh. Chem.111, 289 (1980).     

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.

     

Über die Reaktionen von 2-Cyclohexenonen mit Guanidin

3-Methyl-5-phenyl-2-cyclohexenone (6 a), 3,5-dimethylcyclohexenone6 b, 3-methylcyclohexenone6 c and 2-cyclohexenone (6 d) resp. react with guanidine in toluene and methanol resp. to give the substituted 2,4-diazabicyclo[3.3.1]nonane-3-imines7 a-d. The condensation of isophorone6 e with guanidine (to form7 e) could not be accomplished. The structures of the compounds7 a-d are deduced from their IR- and NMR-spectra; the mechanism and the steric course of the reaction are discussed. Salts of7 a-d were also prepared.7 a andb showed no significant herbicidal and only small fungicidal and insecticidal activities in screening tests.

Vergleiche auch die 58. und 59. Mitt., Mh. Chem., im Druck.     

DMF acetals as alkylating and cyclizing agents: A facile route to substituted pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-diones

Summary Several 7-methyl-5-alkyl-2-vinylpyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-diones were prepared. The successful cyclization and alkylation of 6-(-methylbenzylidenehydrazino)-1-methyluracils2a–d using dimethylformamide acetals at high temperature provided6a–d,7a–d, and8a–d. Treatment of6a–d and7a–d with acid afforded 7-methyl-5-alkylpyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-diones9a,b; under the same conditions,3a–d reacted to 7-methylpyrazolo[3,4-d]-pyrimidine-4,6(5H)-dione (4) in good yield.

---

DMF-Acetale als Alkylierungs- und Ringschlußreagentien: ein einfacher Weg zu substituierten Pyrazolo[3,4-d]pyrimidin-4,6(5H,7H)-dionen

Zusammenfassung Es wurden verschiedene 7-Methyl-5-alkyl-2-vinylpyrazolo[3,4-d]pyrimidin-4,6(5H,7H)-dione hergestellt. Cyclisierung und Alkylierung der 6-(-Methylbenzylidenhydrazino)-1-methyl-uracile2a–d mit Hilfe von Dimethylformamidacetalen bei hohen Temperaturen ergab6a–d,7a–d und8a–d. Behandlung von6a–d und7a–d mit Säure lieferte die 7-Methyl-5-alkylpyrazolo[3,4-d]pyrimidin-4,6(5H,7H)-dione9a,b; unter den gleichen Bedingungen reagierten3a–d in guter Ausbeute zu 7-Methylpyrazolo[3,4-d]pyrimidin-4,6(5H)-dion (4).

     

Stereoselective epoxidation of 2-arylidene-1-indanones and 2-arylidene-1-benzosuberones

Summary Oxidation of the (E) and (Z) isomers of 2-arylidene-1-indanones (1) and 2-arylidene-1-benzosuberones (4) by alkaline hydrogen peroxide (methodi) afforded the spiroepoxidestrans-2a–g andtrans-5a–g from both isomers as sole products in high yields. On the other hand, dimethyldioxirane epoxidation(methodii) of the (E) isomers1a–g and4a–g gave the correspondingtrans spiroepoxides in good yields, whereas the (Z) isomers1a,c,e and4a,c,e led to thecis spiroepoxides in moderate yields. Dimethyldioxirane oxidation (methodii) of (Z)-1c and (Z)-4c,e gave diones3c and6c,e as by-products as well. Epoxidation of (Z)-1a,c,e and (Z)-4a,c,e bym-chloroperoxybenzoic acid (methodiii) resulted inca. 6:1 mixtures ofcis-2a,c,e andtrans-2a,c,e orcis-5a,c,e andtrans-5a,c,e spiroepoxides.Dedicated to Prof.W. Fleischhacker on the occasion of his 65^th birthday     

Studies on sigmatropic rearrangements: Thermal rearrangement of 3-(meta-substituted aryloxymethyl) coumarins

Summary At elevated temperatures, the 3-(meta-substituted aryloxymethyl) coumarins3a–e and3g–k undergo sigmatropic rearrangements to give the hydroxylated 3-benzylcoumarins4a–e and4g–k. Upon methylation and subsequent oxidation with N-bromo succinimide, the 3-(chlorosubstituted benzyl) coumarins4a,4m and4n afford 3-(chlorosubstituted benzoyl) coumarins8a,8m, and8n.

---

Untersuchungen von sigmatropen Umlagerungen: Thermische Umlagerung von 3-meta-substituierten Aryloxymethylcumarinen

Zusammenfassung Bei erhöhter Temperatur reagieren die 3-meta-substituierten Aryloxymethylcumarine3a–e und3g–k über eine sigmatrope Umlagerung zu den hydroxylierten 3-Benzylcumarinen4a–e und4g–k. Methylierung der 3-chlorsubstituierten Benzoylcumarine4a,4m und4n, gefolgt von Oxidation mit N-Bromsuccinimid, ergibt die 3-chlorsubstituierten Benzoylcumarine8a,8m und8n.

     

Synthese von benzanellierten Carbacephamen, 1. Mitt.

Summary The direct intramolecular acylation and alkylation of the phenylsulfonylmethyl-group in the -lactames5a and7 are not successful. The postulated intermediate8 of the acylating reaction could be quenched with trimethylchlorosilane as the stable silylketale10. Desulfonation and desilylation of10 leads to the title compound12. The reaction of7 with base does not result in a carbacephame. Instead, the benzo[b]-azepinones15c,d have been obtained.

     

Strukturelle Abwandlungen anN-Acetylneuraminsäure, 3

From methyl-5-acetylamino-7,8-anhydro-4,9-O-bis-(t-butyldimethylsilyl)-3,5-dideoxy--D-glycero-D-galacto-2-nonulopyranosidonic acid methylester (1) the derivatives1 a and1 b were obtained by removing the 9-O-(t-butyldimethylsilyl)group withBu ₄NF, followed by acetylation. Treatment of1 b with 80% acetic acid and acetanhydride/pyridine yields the 8-epi-N-acetylneuraminic acid derivative2 a and the 7-epi-N-acetylneuraminic acid derivative3 a in a ratio of 3:1 (Scheme 1). The structure elucidation of2 b was achieved by converting2 b via the 4,9-bis-O-(tBDMSi)-8-O-tosyl-derivative2 d into the epoxide1 (Scheme 2). Using the same sequence the epoxides4 and5 were transformed into theN-acetylneuraminic acid derivative6 a and the 7,8-bis-epi-N-acetylneuraminic acid derivative7 a (Scheme 3). After treatment with sodium hydroxide and 0.025m HCl and Dowex 50 H⁺ the 8-epi-, 7-epi- and 7,8-bis-epi-N-acetylneuraminic acids2,3, and7 were obtained. These three compounds were tested withCMP-N-acetylneuraminic acid synthetase.

Herrn KollegenK. Schlögl mit den besten Wünschen zum 60. Geburtstag.     

Über die Darstellung der 7R-Oxirane von 5Z- und 5E-10-Oxo-19-norcholecalciferol

Summary The two title compounds12b and13b have been prepared by direct oxidation of the corresponding 10-oxo-19-norcolcalciferol derivatives3c and4c withMCPBA. The generation of12b and13b by treatment of the ⁷ epoxidized ethylisoxazolin adducts of 5Z- and 5E-cholecalciferol8a,8b and9a,9b with Mo(CO)₆ failed, since besides the retroaldol cleavage of the heterocycle a deoxygenation of the oxirane with retention of configuration to the ⁷ double bond occurs.

     

Synthese von 4-Acetoxy-1-aryl-2-azetidinonen

The 4-carboxy-2-azetidinones1 a,1 b und1 c react with leadtetraacetate/pyridine to give the 4-acetoxy-1-aryl-2-azetidinones2 a, 2 b and2 c. Hydrogenolysis of2 a yields2 d.

     

A study of the Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one derivatives

Summary The Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 a) gave 7-hydroxy-8-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (3 a) and 2,3-dihydro-2,6-diphenyl-3-methyl-(7H)furo[2,3-h]-1-benzopyran-7-one (7 a). 2-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 b) afforded4 b and7 b. 8-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (12) gave only the alkali soluble product 7-hydroxy-8-methyl-6-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (13).3 a,4 b, and13 were further cyclized in acidic medium to9 a,10 b, and14 followed by dehydrogenation.This paper is dedicated to Dr. F. M. Dean, Department of Organic Chemistry, Robert Robinson Laboratories, University of Liverpool, Liverpool, U. K., on his retirement     

Hetero-Diels-Alder reaction of some 1,3-diaza-1,3-butadienes with ketenes. Synthesis of functionalized pyrimido[1,2-b]-benzothiazoles and 1,3,4-thiadiazolo-[3,2-a]pyrimidines

Summary Reaction of 1,3-diaza-1,3-butadienes (1a–c) with various ketenes and chloroketenes results in the formation of substituted 4-oxo-pyrimido[2,1-b]benzothiazoles (4a–d) and 1,3,4-thiadiazolo[3,2-a]pyrimido-4-ones (4e,f). Reaction of 1,3-diaza-1,3-butadienes1d,e with ketenes and chloroketenes leads to the 2-morpholine-substituted compounds7 and15, respectively. All reactions proceedvia formation of [4+2] cycloadducts that eliminate methylthiol, methylsulfenyl chloride, or morpholine.

---

Hetero-Diels-Alder-Reaktion einiger 1,3-Diaza-1,3-butadiene mit Ketenen. Synthese funktionalisierter Pyrimido[1,2-b]benzothiazole und 1,3,4-Thiadiazolo[3,2-a]pyrimidine

Zusammenfassung Die Reaktion der 1,3-Diaza-1,3-butadiene1a–c mit verschiedenen Ketenen und Chlorketenen führt zu substituierten 4-Oxo-pyrimido[2,1-b]benzothiazolen (4a–d) und 1,3,4-Thiadiazolo[3,2-a]pyrimido-4-onen(4e,f). Die 1,3-Diaza-1,3-butadiene1d,e ergeben mit Ketenen und Chlorketenen die 2-Morpholin-substituierten Verbindungen7 und15. Alle Reaktionen verlaufen über [4+2]-Cycloaddukte, die Methylthiol, Methylsulfenylchlorid oder Morpholin eliminieren.

     

Zur Synthese und Struktur derp-Indazolchinone und ihrer Methylierungsprodukte Untersuchungen über Chinone, 8. Mitt.

Summary Thep-benzoquinones5e-j react with diazomethane (after dehydrogenation) to 6-anilino-2e, dimethylamino-2h, phenylthio-2i, and methylthioindazolquinone2j. Methylation with dimethylsulfate of these as well as of the already known indazolquinones 6-toluidino-2f, 6-methylanilino-2g, 5-tert.butyl-2m, 5,6-methyl- (isomer mixture)2l,n, and benz-indazolquinone2o yield the 1-and 2-N-methyl derivatives3 and4. The structure of the 2-methyl derivatives is established by reaction of the corresponding benzoquinones with 3-methylsydnon in the case of4e,4g. UV/VIS-, IR- and¹H-NMR-spectroscopy (in CDCl₃ andDMSO) were used for structure determination. Comparison of the UV/VIS-spectra of2–4 shows that the indazolquinones are existing as 2 H-4,7-diones. For the structure elucidation of the 1- rs. 2-methylderivatives (whichh can be attributed to the methylation products) NMR-spectroscopy is well suited even without knowing the second isomer (solvent-effect). The course of the reaction of quinones with diazomethane and of the methylation reactions of the indazolquinones is discussed.

Herrn Univ.-Prof. Dr. G. Zigeuner zum 70. Geburtstag gewidmet     

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.