C‐Acylierung von 5 gliedrigen N‐Heterocyclen, I. Acylierung an C‐2 von Imidazolen und Benzimidazolen

Abstract

I-Alkyl-und I-Arylimidazole 1 reagieren mit Carbonsaurechloriden in Gegenwart von Triethylamin in polaren Solventien zu den 2-Imidazolylketonen 4, 5 und 7. Analog reagieren die Verbindungen 1 mit Chlorameisensaureestern zu den 2-Imidazolcarbonsaureestern 6; aus 1-Methylimidazol (1, R = CH3) entsteht rnit Oxalsaure-ethylester-chlorid der (I-Methyl-2-imidazolyl)oxoessigsaure-ethylester (75, Tabelle 4). -Unsubstituiertes Imidazol (8) bildet mit Phthalsauredichloriden 9 die Imidazo[l,2-b]isochinolin-5,1O-dione 12, die mit Nucleophilen unter Ringspaltung in die Ketone 13 iibergefiihrt werden. Analog werden mit Benzimidazol die Benzimidazo[l,2-b]isochinolin-6,1l-dione 14 gebildet, die bei der Ringoffnung in die Ketone 15 hbergehen. GAcylation of 5-Membered N-Heterocycles, I. -Acylation at C-2 of Imidazoles and *) Korrespondenz bitte an diesen Autor richten.

Control of the Interactions in Multichromophores: Novel Concepts. Perylene Bis‐imides as Components for Larger Functional Units

“…A remarkable rearrangement was found for the reaction of sterically hindered amines and imidazole with perylene-imide anhydride according to Regels mechanism [42] [43] with the formation of 15 [44]. The UV/VIS spectrum of the latter is nearly congruent with terrylene ( tribenzo[de,kl,rst]pentaphene; 16) (Fig.…”

[1,2]‐Rearrangement of Imino‐N‐heterocyclic Carbenes − Synthesis and Structures of Chelating Iminoimidazole Pd and Ni Complexes

“…1 H NMR spectroscopic data and the boiling point concur with published data. [20] Imidazole 5a: A Schlenk tube was charged with 2,6-diisopropylaniline 9a (2 mL, 10.6 mmol), toluene (40 mL), and 5.3 mL of a 2.0 molar toluene solution of trimethylaluminum (10.6 mmol). The stirred solution was heated to 80°C.…”

“…Ketone 8: [20] A round-bottom flask was charged (without protection from air) with 1-methylimidazole 7 (10 mL, 0.125 mol) and acetonitrile (125 mL). The stirred solution was cooled to 0°C and benzoyl chloride 6 (14.6 mL) was added from a dropping funnel within a period of 15 minutes, followed by addition of triethylamine (17.5 mL, 0.125 mol).…”

“…To this end, benzoyl chloride 6 was reacted with methylimidazole 7 to afford 2-benzoyl-N-methylimidazole (8) by a published procedure (Scheme 3). [20] Introduction of the imine functionality was achieved with aluminum-metalated (1)ϪN (2) anilines 9a, 9b, and 9c in yields of 68%-85%, thereby allowing steric fine-tuning of these [N,N] ligand systems. The aluminum-assisted condensation of carbonyl functionalities with primary amines is a very convenient method, [11a,21] which is especially useful for electronically deactivated and sterically crowded systems.…”

Koordination von Rhodium(III), Iridium(III) und Kupfer(II) mit dem potentiell vierzähnigen Akzeptorliganden Bis(1-methylimidazol-2-yl)glyoxal (big)

“…Der Ligand big Die Synthese des Liganden erfolgte zuna È chst nach der allgemeinen Vorschrift von Regel und Bu È chel [9] fu È r die Acylierung von Imidazolen (Methode A). Die Ausbeute von ca.…”