1: ethyl-α,α,α-trifluoroacetate With sodium methylate in methanol T=0°C; 0.5 h; Inert atmosphere; 2: 1,3-dihydro-1-oxo-2H-indene in methanol T=0 - 20°C; 14 h; Inert atmosphere;

1: 1,3-dihydro-1-oxo-2H-indene With lithium hexamethyldisilazane in tetrahydrofuran T=0 - 20°C; 0.333333 h; 2: TFETFA in tetrahydrofuran T=20°C; 0.333333 h; 3: With ammonium chloride in tetrahydrofuran; water