hydrogen; chiral iridium phosphorothioite on silica in dichloromethane T=40°C; P=15001.5 Torr; 12 h;

1: 3-oxo-1,3-dihydro-isobenzofuran With lithium hexamethyldisilazane in tetrahydrofuran T=-78°C; 0.416667 h; Inert atmosphere; 2: citraconic acid dimethyl ester in tetrahydrofuran T=-78 - 20°C; Inert atmosphere; regioselective reaction;

N-bromosuccinmide; 2,2'-azo-bisisobutyronitrile in tetrachloromethane 24 h; Heating;