Heterocyclen durch Michael‐Reaktionen, 6. Mitt. Synthese von Benzo[h]chinolin‐2‐onen

Abstract

So findet man in den IR-Spektren (KBr) die NH-Schwingungzwischen 3250 und 3370 cm-l, die Nitrilbande bei 2260 cm-' und die Schwingungder Carbonylgruppe beica. 1700 cm-I. Alle 'H-NMR-Spektren zeigen neben den erwarteten Signalen der aromatischen und alicyclischen Protonen im Bereich von 6 = 3.3 bis 5.0 ppm ein AB-System rnit einer Kopplungskonstanten JAB = 6-7 Hz, welches den Protonen an C-3 und C-4 zugeordnet wird. Das Signal des NH erscheint konzentrationsabhangig als verbreitertes Singulett bei etwa 6 = 10 ppm. 4a und 4b sind im iibrigen identisch rnit den aus 1 und Cyanacetamid direkt gewonnenen Produkten').Um Auskunft iiber die Dehydrierungsmoglichkeiten von 4 zu erhalten, haben wir an einzelnen Beispielen die Einwirkung verschiedener Oxidationsmittel untersucht. Dabei

Reactions of carbonyl compounds with α,β-unsaturated nitriles as a convenient pathway to carbo- and heterocycles

“…This provides a route from fused pyrans 280 to pyridine derivatives 281, 178 which are converted into pyridones 282 in acid media. 179 The pyrans 243 are capable of recyclising to pyridones 283 in the CH 3 COOH ± HBr system [pathway (a)]. Apparently, this process begins with the hydrolysis of the cyano group to an amide group with the intermediate formation of pyran 284.…”

A facile and efficient synthesis of bisazine derivatives

“…Isolation of pyran derivatives 15 can take place through treating 1 with ylidenemalononitrile derivatives 13a-c in dioxane/triethylamine. Transformation of pyran 15 to the bispyridine derivatives 16 took place by heating in a mixture of glacial acetic acid/ammonium acetate mixture similar to that reported earlier [14,[19][20][21]. These reaction products 16a-c were established based on IR which reveals the presence of cyano group and amide carbonyl at expected regions.…”

Chemistry of Seven-Membered Heterocycles, VI. Synthesis of Novel Bicyclic Heterocyclic Compounds as Potential Anticancer and Anti-HIV Agents

“…A n alternative synthesis of both com pounds 6 and 7 involved the reaction of the k e tones 4 [1] and 5 [3] ever, when the ketones 4 and 5 w ere reacted with m alononitrile in the presence of sodium acetate in refluxing ethanol or in ethanol-piperidine m ixture at room tem p eratu re, the corresponding fusedring pyrans 8 and 9 w ere form ed. Taking into account the fact that such type of pyrans u ndergo rearran g em en t u n d er acidic conditions to the dihydropyridones [7,8], we w ere able to convert 8 to 8-aryl-10-oxo-6,7,8,9,10,ll-hexahydro-l-benzothiepino[5.4-fr]pyridine-9-carbonitrile-S,S-dioxide (10) by passing gaseous hydrogen chloride in ethanol suspension of 8 at 0 °C.…”

“…85% yield (see Table 1). (7) This com pound was prep ared from 3 and 5 ac cording to the procedure described above for the Brought to you by | New York University Bobst Library Technical Services Authenticated Download Date | 6/18/15 7:25 AM…”