Synthese von basisch substituierten 5H‐Pyrimido[4,5‐c]‐2‐benzazepinen

Abstract

Die potentiell ZNS-wirksamen Titelverbindungen 19a-c lassen sich durch eine neunstufige Synthese ausgehend von Phthalaldehydsaure herstellen. Durch Knoevenagel-Kondensation von 5 mit den Acetonitrilen 2a-g und folgender Reduktion mit NaBH4 erhiilt man die Dihydrozimtsaurenitrile 3. Nur 3a la3t sich zu den 2-Benzazepinnitrilen 9a.b cyclisieren. Ammonolyse von 9a fiihn zum Enaminonitril 10, das mit den Orthoestem lla-c die Imidsaureester 12a-c gibt. Nachfolgende Ammonolyse liefert die Tricyclen 16a,b. Nach Umwandlung der Lactamfunktion von 16 in das Imidoylchlorid 17 folgt Aminolyse mit den Aminen 18a-c zu den Titelverbindungen 19a-c. Synthesis of Basically Substituted SH-Pyrimido[4,5-~]-2-benzazepinesThe potentially CNS-active title compounds 19a-c can be prepared by a nine step synthesis beginning with phthalaldehydic acid. Knoevenagel condensation of 5 with the acetonitriles 2a-g and subsequent reduction with NaBH4 lead to the dihydrocinnamic acid nitriles 3. Only 3a can be cyclized to the 2-benzazepinnitriles 9a,b. Ammonolysis of 9a yields the enaminonitrile 10, which is reacted with the orthoesters lla-c to the imidic acid esters 12a-c. Ammonolysis leads to the tricycles 16a,b. After transformation of the lactam group in 16 to an imidoyl chloride 17, aminolysis with the amines 18a-c provides the title compounds 19a-c. Im Rahmen der

Aryl(hetaryl)-containing gem-cyanonitroethenes: Synthesis, structure, and reactions with 2,3-dimethyl-1,3-butadiene

“…E-Configuration of one of the gem-cyanonitroethenes, 2-(2-methoxycarbonylphenyl)-1-nitro-1-cyanoethene (δ HA = 9.49 ppm), stated earlier[8] was additionally confirmed by the value of the heteronuclear coupling constant between the H A proton and the carbon atom of cyano group [ 3 J(H А C 1 ) ≈ 14 Hz] corresponding to their trans-location. That constant was observed in the proton-coupled 13 C NMR spectra of E-gem-cyanonitroethenes I-VI recorded in this work [ 3 J(H А C 1 ) = 10.86-11.70 Hz].…”

“…The 13 C NMR spectra of certain representatives of gem-cyanonitroethenes have been reported earlier [10,[12][13][14]28] but the signal assignment has not been accomplished; complete assignment of the 13 C NMR signals has been performed only for β-(2-methoxycarbonylphenyl)-α-nitroacrylonitrile [8]. 13 C NMR spectra of gem-cyanonitroethenes I-VI recorded in this work (Table 2) contained the signals of all the carbon atoms present in the structures.…”

“…Aryl(hetaryl)-containing gem-cyanonitroethenes have been prepared via condensation of the corresponding aldehydes with nitroacetonitrile under various conditions: in the presence of methylamine or ethylamine hydrochlorides and sodium carbonate [2][3][4][5][6][7], β-alanine [8], n-propylamine [9], Iran dolomite [10], and on silica gel [11]. Preparation of nitrile of α-nitrocinnamic acid and its analogs via alkenylation of nitroacetonitrile with aldehydes in aqueous medium [12], solvent free conditions [13], in ionic liquids [14a], and under microwave irradiation [14b] has been reported.…”

Chemistry of 2-aryl-1-cyano-1-nitroethenes. Part I. Synthesis and physical properties

“…An analogous methodology was also applied later in the case of ACNs 2, 7, 10, 14, 15, 23 and 25 [21][22][23][24]. Later [18,[25][26][27]28], other aliphatic and alicyclic amines (n-propylamine, n-pentylamine, morpholine, ethylenediamine, β-alanine) were also tested as catalysts in similar syntheses. In these syntheses several new compounds were prepared.…”

Regioselective reduction of 2-cyanoprop-2-enethioamides with sodium borohydride

“…15, 16 Despite an obviously conve nient introduction of an alkyl fragment into active methyl ene thioamides by a tandem process involving the Knoe venagel condensation/reduction of the C=C bond, we found only one example of such a transformation in the literature. 17 In the present work, we tried to study the possibility of obtaining C alkylated derivatives of cyanothioacetamide via reduction of products of its condensation with carbon yl compounds. It turned out that reduction of 2 cyano prop 2 enethioamides 1 with LiAlH 4 in boiling diethyl ether proceeds nonselectively to give a complex mixture of products, regardless of the reaction conditions and the ratio of the reagents.…”