ChemInform Abstract: Copper‐Catalyzed C(sp³)—C(sp²) Cross‐Coupling: Synthesis of 4‐Aryl‐2‐alkylamino‐3‐nitro‐4H‐chromenes.

Abstract

Cu(II)‐catalyzed coupling of 4‐(methylthio) substituted 3‐nitro‐4H‐chromen‐2‐amines with arylboronic acids provides the corresponding 4‐aryl derivatives in good yields.

K2CO3-Mediated Synthesis of Functionalised 4-Substituted-2-amino-3-cyano-4H-chromenes via Michael-Cyclization Reactions

“…As a result, considerable efforts have been made over the past decades for the synthesis of 2-amino-4 H -chromenes [17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47], which is accomplished using various catalysts including diethylamine [26], ethylenediamine diacetate [27], I 2 [28], PEG [29], β-cyclodextrin [30], InCl 3 [31,42,43], guanidine [32], ammonium acetate [46], Al 2 O 3 [47], Zr(KPO 4 ) 2 [44], molecular sieves [45], aminosilane- modified Fe 3 O 4 nanoparticles [33] and silica-bonded 2-hydroxyethylammonium acetate (HEAA) [34]. In addition, some enantioselective synthesis methodologies for 2-amino-4 H -chromenes were also documented in the literature [22,23,35,36,37,38,39].…”