Selective Metal-Controlled Synthesis of Trifluoromethylated (Indolin-2-ylidene)methyl- and Quinolin-3-ylphosphonates

J Org Chem. 2020 Nov 20;85(22):14507-14515. doi: 10.1021/acs.joc.0c00913. Epub 2020 Jul 6.

Abstract

Metal-catalyzed (Cu, Ag, Au) reactions of alkynylphosphonates with 1-(2-aminophenyl)-2,2,2-trifluoroethan-1-ones were developed. Terminal alkyne diethyl ethynylphosphonate reacted with ketones to give different products depending on the catalyst used. With a CuI/PPh3 catalytic system, the formation of CF3-containing indoline derivatives was observed with good yields. The use of AgSbF6 as a catalyst led to quinoline derivatives in high yields. The less reactive 2-substituted ethynylphosphonates required gold complexes as catalysts to provide the corresponding 2-aryl(alkyl) substituted 4-(trifluoromethyl)quinolin-3-ylphosphonates with good yields.