A three-component reaction between azaarenes (phenanthridine, quinoline or isoquinoline), acetylenic esters and phenol derivatives

Abstract

Three component condensation reactions between azaarenes (phenanthridine, quinoline or isoquinoline) and acetylenic esters were undertaken in the presence of phenol derivatives (2,4-di-tert-butylphenol, 2,6-dimethylphenol, 4methylphenol and 4-chloro-3,5-dimethylphenol) for generation of C-arylation in good yields. The reactions proceeded smoothly at room temperature without using any catalyst.

A Novel Three-Component Reaction Involving Benzothiazole, Dialkyl Acethylenedicarboxylate and 1,3-Dicarbonyl Compounds or Anthrone

“…The 1 H NMR of each of the isolated products 4a-g exhibited a N-C=CH proton signal at about 6.58-6.78 ppm, which is in agreement with the ( Z) configuration [22][23][24] for the vinyl moiety in 4a-g. (see Scheme 1 and Table 1).…”

“…The 1 H and 13 C NMR spectra of 4b-g are similar to those of 4a except for the carbonyl moieties, which exhibited characteristic resonances in appropriate regions of the spectrum. The 1 H NMR of each of the isolated products 4a-g exhibited a N-C=CH proton signal at about 6.58-6.78 ppm, which is in agreement with the ( Z) configuration [22][23][24] for the vinyl moiety in 4a-g. (see Scheme 1 and Table 1).…”

Synthesis of 4- or 6-(3-Benzyl-2,3-Dihydrobenzo[d]Thiazol-2-yl)Phenol Derivatives by a Novel Three-Component Reaction

“…In addition, product 4a displayed 13 C NMR resonances at δ = 29.2, 30.1, 52.2, 92.4 and 146.1 ppm respectively for the 2CMe 3 , N-CH 2 , S-CH-N and C-OH. 14,[17][18][19][20][21] The 1 H NMR and 13 C NMR spectra of 4b-f are similar to those of 4a. Although the mechanistic details of the reaction are not known, a plausible rationalisation may be advanced to explain the product formation (see Scheme 1 and Table 1).…”

“…For example, the 1 H NMR spectrum of 4a exhibited four signals at δ = 0.93 and 1.38 ppm (18H, 2s, 2CMe 3 ), 5.25 (2H, s, CH 2 ) [13][14][15] and 5.83 (1H, s, OH). 16,17 The aromatic protons gave multiplets at δ = 6.98-7.49 ppm for the benzothiazole, benzyl and phenol moieties and the S-CH also gave a signal in this range. The 13 C NMR spectrum of 4a showed 22 distinct resonances in agreement with the proposed structure.…”

Synthesis of Spiro Pyrrolobenzothiazole Derivatives via a Three‐Component Reaction

“…The reaction of 2‐methylbenzothiazole or 2,5‐dimethylbenzothiazole 1 with acetylenic esters 2 as a Michael acceptor in the presence of 1,3‐dicarbonyl compounds 3 at ambient temperature in CH 2 Cl 2 leads to spiro pyrrolobenzothiazole derivatives 4 in good yields (see Schemes and and Table ). The reactions were carried out by first mixing 1 and 3 , and then the acetylenic esters 2 was added slowly and were complete within 8 h. The structures of compounds 4a , 4b , 4c , 4d , 4e , 4f were assigned on the basis of their IR, 1 H NMR, 13 C NMR, elemental analysis and mass spectral data.…”