Cobalt complex catalyzed atom-economical synthesis of quinoxaline, quinoline and 2-alkylaminoquinoline derivatives

Abstract

A new phosphine-free Co(ii) complex-catalyzed synthesis of various quinoxalines via dehydrogenative coupling of vicinal diols with both o-phenylenediamines and 2-nitroanilines is reported. This complex was also effective for the synthesis of quinolines. The practical aspect of this catalytic system was revealed by the one-pot synthesis of 2-alkylaminoquinolines.

Phosphine Ligand‐Free Ruthenium Complexes as Efficient Catalysts for the Synthesis of Quinolines and Pyridines by Acceptorless Dehydrogenative Coupling Reactions

“…These metal‐catalyzed catalytic cycle involves dehydrogenation of alcohols, followed by cyclo‐condensation with amines, with only H 2 and H 2 O as by‐products. Among various homogeneous transition metal catalysts, Ru‐complexes are the most efficient reported to date ,. Metal‐ligand cooperative catalysis can dramatically improve catalytic performance of ADC reactions using pincer ligands bearing NH, OH or CH 2 functionality ,.…”

Iron Catalyzed Synthesis of Pyrimidines Under Air

“…However, reports with inexpensive and earth‐abundant base metal catalysts are limited . Therefore, to make the sustainable dehydrogenative alcohol functionalization reactions more environmentally benign and economically affordable, the expensive and scarce noble metals need to be substituted by comparatively less costly and environmentally benign base metals such as manganese,–– iron, cobalt,–– nickel,– etc.…”

Synthesis of Quinolines Through Acceptorless Dehydrogenative Coupling Catalyzed by Rhenium PN(H)P Complexes

“…[9] Severalc atalytic systemsb ased on group 8t o1 0t ransition metals( Ru, [10] Rh, [11] Pd, [12] Ir, [13] Au, [14] Cu, [15] Co [16] )h ave been developed. [9] Severalc atalytic systemsb ased on group 8t o1 0t ransition metals( Ru, [10] Rh, [11] Pd, [12] Ir, [13] Au, [14] Cu, [15] Co [16] )h ave been developed.…”