1: tetrabutyl ammonium fluoride / tetrahydrofuran / 3 h 2: dimethyl sulfoxide; oxalyl dichloride / dichloromethane / 1 h / -60 - -50 °C 3: sodium chlorite; sodium dihydrogen phosphate dihydrate; 2-methyl-but-2-ene / water; tert-butyl alcohol View Scheme

1: tetrabutyl ammonium fluoride / tetrahydrofuran / 3 h 2: dimethyl sulfoxide; oxalyl dichloride / dichloromethane / 1 h / -60 - -50 °C View Scheme

dichloro bis(acetonitrile) palladium(II); oxygen; copper(l) chloride in water; N,N-dimethyl-formamide Wacker oxidation;