Zur Umsetzung offenkettiger Imide mit 1‐Ethoxycarbonylcyclopropyltriphenylphosphonium‐tetrafluoroborat: Ein einfacher Weg zu 1H‐Pyrrol‐3‐carbonsäureestern

Abstract

Durch Umsetzung der Anionen offenkettiger Imide 1 mit dem Cyclopropylphosphoniumsalz 2 werden 2‐substituierte 1‐Acyl‐Δ2‐pyrrolin‐3‐carbonsäure‐ethylester 3 erhalten, die zu den entsprechenden 1‐acylierten 3‐Pyrrolcarbonsäureestern 4 dehydriert und anschließend zu Pyrrolen 5 de‐acyliert werden. Die Anwendungsbreite der Reaktionsfolge wird beschrieben.

Synthesis of Novel Furo-, Thieno-, and Pyrroloazepines

“…The residue was purified by column chromatography (hexane-EtOAc, 8:2) to afford 11 (2.0 g, 75%) as a pale yellow oil. Spectroscopic data agreed well with results previously reported in the literature 15.…”

Synthesis of γ-Azido-β-ureido Ketones and Their Transformation into Functionalized Pyrrolines and Pyrroles via Staudinger/aza-Wittig Reaction

“…The precipitate was filtered and dried to give 17l (0.353 g, 83%). Mp 73.5–75 °C (lit . mp 68 °C); IR (Nujol) ν max 3330 (s), 3266 (vs) (NH), 3055 (w), 3020 (w) (CH arom ), 1679 (vs) (CO), 1607 (w), 1580 (m), 1563 (m) (CC arom ), 1292 (vs), 1143 (vs) (C–O), 764 (s), 697 (m) (CH arom ) cm –1 ; 1 H NMR (300.13 MHz, DMSO- d 6 ) δ 11.62 (br s, 1H, NH), 7.56–7.61 (m, 2H, ArH), 7.31–7.44 (m, 3H, ArH), 6.85 (dd, 3 J = 2.9, 3 J = 2.5 Hz, 1H, H-5), 6.54 (dd, 3 J = 2.9, 4 J = 2.5 Hz, 1H, H-4), 4.11 (q, 3 J = 7.1 Hz, 2H, OCH 2 ), 1.18 (t, 3 J = 7.1 Hz, CH 3 ); 13 C NMR (75.48 MHz, DMSO- d 6 ) δ 164.2 (CO), 136.2 (C-2), 132.0 (C), 129.0 (2CH), 127.7 (2CH), 127.6 (CH), 118.5 (C-5), 111.3 (C-4), 111.1 (C-3), 58.8 (OCH 2 ), 14.2 (CH 3 ).…”

Microwave-Assisted Synthesis of Acyclic Imides

“…Many drugs containing the imide group exhibit so many different biological activities such as immunosuppressants (Koehn et al, 1992), cytotoxic anticancer agents (Pettit et al, 1989), antibiotics (Nakamura et al, 1974) and antifeedans (Nagle et al, 1996). Also, imides are important precursors in the synthesis of nitrogen-containing heterocyclic compounds (Flitsch et al, 1983(Flitsch et al, , 1990Lee et al, 2012).…”