An efficient one-pot synthesis of dialkyl 8a-acetylamino-8-oxo-8,8a-dihydro-2H-1-oxacyclopenta[α]indene-2,3-dicarboxylate derivatives

Abstract

Ninhydrin reacts with amides in ethanol to produce N- (2-hydroxy-1,3-dioxoindan-2-yl)amide derivatives in nearly quantitative yields. Reaction between these adducts and electron-deficient acetylenic esters in the presence of triphenylphosphine leads to dialkyl 8a-acetylamino-8-oxo-8,8a-dihydro-2H-1-oxacyclopenta[α]indene-2,3-dicarboxylate derivatives in good yields.

Recent applications of ninhydrin in multicomponent reactions

“…2,3 In fact, ninhydrin is a strong electrophile that reacts with nucleophiles such as ammonia, amines, enamines, ureas, amides and anilines. [2][3][4][5][6] Primary amines and aamino acids react readily with ninhydrin at the central carbon to produce a highly coloured, condensation product known as Ruhemann's purple. Besides nitrogen-based nucleophiles, its C-2 position is reactive towards various carbon-, oxygen-and sulphur-based nucleophiles, resulting in C-C, C-O and C-S bonds, respectively.…”

Catalyst- and Base-Free Synthesis of Morita–Baylis–Hillman and Rauhut–Currier Adducts of β-Aminonitroalkenes

“…Further, to show the synthetic utility of the ninhydrin adducts 5 , selected diols were treated with DMAD in the presence of PPh 3 which led to the formation of tricyclic products 11a and 11b as single diastereomers that possess three chiral centers (Scheme a) . According to the proposed mechanism, PPh 3 attacks DMAD 10 and the resulting enolate undergoes protonation by 5 to generate intermediates I and II .…”

Ninhydrin in synthesis of heterocyclic compounds

“…There are many published articles on the different reactions of ninhydrin, such as amidoalkylation, 60 Knoevenagel condensation, 61 oxidation, [62][63] reduction, [64][65][66] aldol addition, [67][68][69][70][71][72][73][74] cycloaddition, 75 Friedel-Crafts type reaction, [76][77][78][79][80][81][82][83] Kolbe-Schmitt, 84 Passerini, [85][86][87][88][89][90][91][92] Wittig, [93][94][95][96][97][98][99][100][101][102][103][104][105][106] and Morita-Baylis-Hillman reactions. [107][108][109]…”