Unexpected isocyanide-based cascade cycloaddition reaction with methyleneindolinone

Abstract

An unprecedented cascade reaction of isocyanide and methyleneindolinone has been established, which represents a novel and different reaction mode. This present transformation involves the ring-opening of methyleneindolinone and the construction of two other new rings simultaneously in an atom-economic manner.

Isocyanide-based multicomponent reactions in the synthesis of heterocycles

“…There are numerous reports in the literature regarding the utility of isocyanide chemistry for synthesis of various indole derivatives [157][158][159][160][161][162][163][164][165][166][167][168][169][170] …”

BF3·OEt2 Mediated Regioselective Reaction of Electron-Rich Arenes with 3-Ylidene Oxindoles

“…Gratifyingly, the reaction of 3-ylidene oxindoles with resorcinol (10) showed excellent diastereoselectivity and the products 25−29 were all obtained as single isomers According to the literature, the reaction of 3-ylidene oxindoles with electron-rich partners at the α-position exhibits less diastereoselectivity. The reactions of 3-ylidene oxindoles with nitromethane 24 and thiophenol 25 Based on the above results and literature studies, 28 a possible mechanism for the formation of 25 was proposed (Figure 3). Association of BF 3 •OEt 2 with 3-ylidene oxindole 1 results in the F−C reaction of resorcinol on the α-carbon of the double bond at position 3, which was then followed by the nucleophilic attack of phenolic OH on the carbonyl group attached to arene; hence, cyclization occurred.…”

“…Based on the above results and literature studies, a possible mechanism for the formation of 25 was proposed (Figure ). Association of BF 3 ·OEt 2 with 3-ylidene oxindole 1 results in the F–C reaction of resorcinol on the α-carbon of the double bond at position 3, which was then followed by the nucleophilic attack of phenolic OH on the carbonyl group attached to arene; hence, cyclization occurred.…”

A One‐Pot Ring‐Opening/Ring‐Closure Sequence for the Synthesis of Polycyclic Spirooxindoles

“…On the other hand, ring‐openings of 3‐oxindole derivatives offer interesting approaches for constructing novel heterocycles, in which cleaving the chemically inert oxindole moiety would enable versatile reorganization of cyclic frameworks . In 2013, Jia and co‐workers reported an elegant ring‐opening cascade reaction of methyleneindolinone with isocyanide to generate quinoline skeletons . Thereafter, Zhao and Hu developed an asymmetric cascade reaction of naphthols and 3‐trifluoroethylidene oxindoles to install dihydrocoumarin skeletons by a sequential intramolecular amide C−N bond‐cleavage and esterification process .…”