Regioselective Synthesis of Fused Furans by Decarboxylative Annulation of α,β‐Alkenyl Carboxylic Acid with Cyclic Ketone: Synthesis of Di‐Heteroaryl Derivatives

Abstract

a,b-Alkenyl carboxylicacids undergo Cu II -mediated decarboxylative annulation reactions with aliphatic cyclic ketones to provides ynthetically valuable di-heterocycles.T he annulation process tolerates avariety of aliphatic ketones and heterocyclic alkenyl carboxylic acids,p roducing substituted fused furan derivatives with complete regioselectivity.T he current protocol offers as ynthetically applicable pathway to construct avariety of oligo-heterocycles through Cu-mediated single-electron transfer and decarboxylation. Notably,s ynthesis of relatively inaccessible di-heterocycles has been achieved successfully using this protocol.

Ruthenium(ii)-catalyzed chemoselective deacylative annulation of 1,3-diones with sulfoxonium ylides via C–C bond activation

“…In continuation of our research on C–C(CO) bond cleavage reactions,8 herein we disclose the first ruthenium-catalyzed deacylative annulation of 1,3-diones with sulfoxonium ylides (Scheme 1c). This method provides a practical and mild synthetic route to substituted furans,9 which are essential structural moieties in many biologically active compounds, natural products, and functional materials 10…”

Recent Advances of Cinnamic Acids in Organic Synthesis

“…A high temperature was good for the E configuration of alkenes . Furthermore, the cascade could involve a cyclization or oxidative coupling to get epoxides, ketones or furans (Scheme ). Reactions were typically carried out in the oxidants (such as di ‐tert‐butyl peroxide (DTBP), K 2 S 2 O 8 , Ag 2 O, tert ‐butyl hydroperoxide (TBHP), dicumyl peroxide (DCP)), electricity or photocatalysis conditions.…”

“…, acyl and ketonic radicals were reported. Toluene, boron reagents, aldehydes, acids, amides, ketones, ethers, alcohols, epoxides, nitriles were able to function as radical precursors.…”

“…In 2019, the Maiti group developed the decarboxylative radical annulation of cinnamic acids with cyclic ketones. Aryl groups in Ar position were better than heterocyclic ones for these transformations (71–90%).…”

DFT Study on the Gold(I)‐Catalyzed Dehydrogenative Heterocyclization of 2‐(1‐Alkynyl)‐2‐alken‐1‐ones to form 2,3‐Furan‐Fused Carbocycles: Effects of Additives C5H5NO vs. PhNO

“…As we know, the many synthetic strategies including Paal‐Knorr reaction and Feist‐Benary reaction have been developed, but the construction of privileged five‐membered oxygenated heterocycles is still a challenge. Recently, the transition‐metals have been widely employed to promote the synthesis of substituted furans as catalysts under the mild reaction conditions . For instance, Trost et al disclosed a successful catalytic (3 + 2) cycloaddition involving Pd‐oxyallyl species to yield a diverse range of cis‐fused methylene tetrahydrofurans .…”