One-pot four-component approach for the construction of dihydropyridines and dihydropyridinones using amines and activated alkynes

Homophtalonitrile for Multicomponent Reactions: Syntheses and Optical Properties of o‐Cyanophenyl‐ or Indol‐3‐yl‐Substituted Chromeno[2,3‐c]isoquinolin‐5‐Amines

“…Based on the literature [9] and our experimental observations, [6] we believe that the interaction of homophtalonitrile 1 with salicylaldehyde 2 starts with Knoevenagelc ondensation, giving astyryl derivativethat may undergo two consecutive in- uct 3a may be converted to 4a under the action of an indole, which looks less reversible owing to aromatization of an indole moiety.T his hypothesis, and the reactionp athway itself, was supported by heating product 3a with an excess indole in a microwave reactor for 10 min at 150 8Ca nd isolation of product 4a in 75 %y ield. The synthesized compounds were noticed to be fluorescent, that is, emitting blue light when exposed to UV radiation ( Figure 4).…”

3,6-Dioxaoctamethylenediamminium trifluoromethanesulfonate [3,6-DOMDA]OTf as a novel ionic liquid catalyst for the synthesis of functionalized 1,4-dihydropyridines

“…Moreover, 4-bromoaniline took shorter time than 4-chloroaniline, 4-methyl aniline and aniline respectively to react, and afforded higher yield of corresponding products. On the basis of our survey on the literature, a possible mechanism for the domino one-pot four-component synthesis of functionalized 1,4-dihydropyridines using [3,OTf as an IL catalyst has been suggested in Scheme 2 [11][12][13][14][15][16][17][18]. In view of a greener chemistry, efficient recovery and reusability of the catalyst is very desirable.…”

“…NaOH [15], piperidine [16], SDS [17], L-proline [18], sulfated boric acid-functionalized MNPs [19] and etc. Since, 1,4-DHPs are good candidates for drug components, their synthesis and applications has been extensively reviewed [20].…”

Piperidine Catalyzed Four-component Strategy for the Facile Access of Polyfunctionalized 1,4-Dihydropyridines at Ambient Conditions

“…In addition to that, we have also studied the quantity of catalyst required for the maximum conversion by carrying out the above model reaction with different mol% of piperidine (10, 20 and 30 %) and found that 20 mol% of the catalyst was sufficient to this four‐component strategy for the convenient access of 1,4‐DHP motifs (Scheme ). On the other hand, the catalytic efficacy of piperidine for these MCRs to synthesize 4‐aryl‐1,4‐dihydropyridine‐2,3‐dicarboxylates was compared with earlier reported catalysts for similar conversions and found that the efficiency of piperidine is good or comparably better than most of the reported catalysts as shown in Table .…”