4 A molecular sieve; pyridinium chlorochromate in dichloromethane 48 h; Ambient temperature; Yield given;

1: lithium dicyclohexylamide / tetrahydrofuran / 1 h / -78 °C 2: PCC, molecular sieves 4A / CH2Cl2 / 48 h / Ambient temperature View Scheme

1: in toluene T=65°C; Schlenk techniqueInert atmosphere; 2: With N-bromosuccinmide in toluene T=-78°C; Schlenk techniqueInert atmosphere; 3: With water in toluene T=20°C; 1 h; Schlenk techniqueInert atmosphere; regioselective reaction;

1.1: thionyl chloride; N,N-dimethyl-formamide / dichloromethane / 2.33 h / 0 - 20 °C 2.1: dichloromethane; tetrahydrofuran / 20 °C / |Cooling with ice 3.1: toluene / 65 °C / |Schlenk technique; |Inert atmosphere 3.2: -78 °C / |Schlenk technique; |Inert atmosphere 3.3: 1 h / 20 °C / |Schlenk technique; |Inert atmosphere View Scheme

2,2,6,6-tetramethylpiperidinyl-lithium 1) THF, hexanes, -98 deg C, 5 min, 2) -98 deg C, 10 min; Yield given. Multistep reaction;

1.1: dichloromethane; tetrahydrofuran / 20 °C / |Cooling with ice 2.1: toluene / 65 °C / |Schlenk technique; |Inert atmosphere 2.2: -78 °C / |Schlenk technique; |Inert atmosphere 2.3: 1 h / 20 °C / |Schlenk technique; |Inert atmosphere View Scheme

Yield given. Multistep reaction;

Yield given. Multistep reaction. Yields of byproduct given;