Synthesis of functionalized and fused furans and pyrans from the Morita–Baylis–Hillman acetates of nitroalkenes

A Reagent‐Free Oxidative Cyclization Approach to Indolizine Derivatives from α‐Picoline Derivatives and Nitroolefins

“…Based on the experimental results and previous reports, [6] we propose the reaction mechanism shown in Scheme 3. In this mechanism, methyl 2-(pyridin-2-yl)acetate (1 a) and 1-(2-nitroprop-1-enyl)benzene (2 a) first undergo a Michael addition to produce intermediates 5 and 6.…”

“…The molecular ion (m/z = 44) and fragments ion (m/z = 30) peaks revealed the generation of N 2 O (see the Supporting Information for further details). In addition, when we added CoCl 2 and KCl to the reaction mixture after completion of the standard reaction, we did not observe the golden yellow precipitate of K 3 [CoA C H T U N G T R E N N U N G (NO 2 )] 6 , which illustrates that nitrite was not formed in the system.…”

Synthesis of pyrazole fused pyran analogues: Antimicrobial, antioxidant and molecular docking studies

“…A variety of functionalized 6-(trifluoromethyl)-6H-dibenzo[b,d]pyrans synthesized by a domino reaction of 3-nitro-2-(trifluoromethyl)-2H-chromenes with 2-(1-phenylethylidene)-and 2-(1-phenylpropylidene)malononitriles [11]. The Morita-Baylis-Hillman (MBH) acetates derived from nitroalkenes and ethyl glyoxylate have been transformed in one pot to highly fused and functionalized furans and pyrans [12]. Studies have shown that pyran derivatives exhibit antimicrobial activities [13].…”

1,3-Diketones. Synthesis and properties

“…A probable reaction mechanism is also shown. Polyfunctional polycyclic and fused systems containing a furan (197e, 197f) or pyran fragment (200) were obtained by regioselective cascade reactions of β-dicarbonyl compounds with MBH (Morita-Baylis-Hillman) acetates 201 derived from nitroalkenes and ethyl glyoxalate [141] (Scheme 129). The reactions initiated by DABCO involved the Michael-5-exo-trigoxa-Michael sequence for acyclic and six-membered cyclic β-diketones, yielding the corresponding furan derivatives 197e and 197f.…”