Studies with condensed amino‐thiophenes: Further investigation of reactivity of amino‐thieno‐coumarines and amino‐thieno‐benzo[h]coumarines toward electron‐poor olefins and acetylenes

Abstract

ABSTRACT:The reaction of 3-amino-5-oxa-2-thiacyclopenta[a]naphthalene-4-one 2b with substituted acetylenes afforded C-1 alkylation products. On the other hand, reaction of 17-amino-15-methyl-11-oxa-16-thiacyclopenta[a]phenanthrene-12-one 5 with substituted acetylenes and electron-poor olefins afforded the condensed thienopyridine derivatives 7 and 11a-c. The reaction of 5 with acrylonitrile and with 4-phenyl-1,2,4-triazoline-3,5-dione

Synthesis and antimicrobial activities of some novel bis-pyrazole derivatives containing a hydrophosphoryl unit

“…The oxidation reaction of compound 6 with selenium dioxide in dry dioxane yielded bis{chromeno [4,3-c]pyrazol-4-oxo-2-yl}phosphine oxide (7) (Scheme 7). The absorption band of carbonyl groupappeared at 1652 cm -1 [34,35] in the IR spectrum of 7. Also, its structure was confirmed from 1 H NMR spectrum by disappearance of OH and C2-H protons of compound 6.…”

Studies with condensed aminothiophenes: Further investigation on the reactivity of condensed aminothiophenes toward electron poor and acetylenes under microwave heating

“…5,168.6,158.9 (CO),148.9,140.0,136.3,135.8,134.6,132.6,129.4,128.8,128.5,125.6,124.3,124.1,123.2,123.0,119.0,114.1,112.8,111.6,46.7 (CH 2 ,3.36;N,5.83;S,6.67. Found C,67.16;H,3.63;N,5.98;S,4,5,pyridazine-1-carboxylic acid (12).…”

Alkyl heteroaromatic as precursors to polycyclic heteroaromatics: Recent developments

“…Moreover, several aminothienopyridazines were hydrolysed in acid media to produce the corresponding thiophenones 96. ref. [13,14,31,32,[43][44][45][46][47][48][49] ref. [16] ref.…”

“…8 Elnagdi et al 48 investigated the reaction of 91a with ethyl propiolate in the cold to yield a 1:1 adduct that had been earlier assumed to be a thiepinochromone 112b. High resolution 1 H NMR analysis of this product indicated the presence of two trans coupled olefinic protons at δ 5.90 and 8.23 ppm with J = 13.7 Hz.…”

“…Consequently a C-1 alkylation was established via a dipolar cycloaddition sequence leading to the formation of 114b. 48 Compound 91a reacted in the same way with DMAD 100b to yield the C-1 alkylated product 114a.…”