1.1: manganese(IV) oxide / isobutyramide / 60 h / 25 °C / Inert atmosphere 2.1: pyridine; cinchonine / tetrahydrofuran / 1.75 h / -25 °C / Inert atmosphere 3.1: calcium chloride; sodium tetrahydroborate / ethanol; tetrahydrofuran / 8.5 h / -7 - 5 °C 3.2: 5 °C 4.1: N-ethyl-N,N-diisopropylamine; methanesulfonyl chloride; sodium carbonate / water; tetrahydrofuran / 6 h / 10 - 57 °C View Scheme

manganese(IV) oxide in ethyl acetate T=40 - 45°C; 6 h;

1.1: manganese(IV) oxide / isobutyramide / 60 h / 25 °C / Inert atmosphere 2.1: pyridine; cinchonine / tetrahydrofuran / 1.75 h / -25 °C / Inert atmosphere 3.1: calcium chloride; sodium tetrahydroborate / ethanol; tetrahydrofuran / 8.5 h / -7 - 5 °C 3.2: 5 °C View Scheme