dipyridinium dichromate in N,N-dimethyl-formamide T=30°C; 15 h;

1: trifluoroacetic acid / methanol / 0 °C 2: dipyridinium dichromate / N,N-dimethyl-formamide / 15 h / 30 °C View Scheme

1.1: n-butyllithium / tetrahydrofuran; hexane / 0.67 h / -20 °C 1.2: -20 °C 2.1: NiII chloride hexahydrate; sodium tetrahydroborate / tetrahydrofuran; methanol / 0 - 30 °C 3.1: trifluoroacetic acid / methanol / 0 °C 4.1: dipyridinium dichromate / N,N-dimethyl-formamide / 15 h / 30 °C View Scheme

1.1: n-butyllithium / tetrahydrofuran; hexane / 0.67 h / -20 °C 1.2: -20 °C 2.1: NiII chloride hexahydrate; sodium tetrahydroborate / tetrahydrofuran; methanol / 0 - 30 °C 3.1: trifluoroacetic acid / methanol / 0 °C 4.1: dipyridinium dichromate / N,N-dimethyl-formamide / 15 h / 30 °C View Scheme

1: NiII chloride hexahydrate; sodium tetrahydroborate / tetrahydrofuran; methanol / 0 - 30 °C 2: trifluoroacetic acid / methanol / 0 °C 3: dipyridinium dichromate / N,N-dimethyl-formamide / 15 h / 30 °C View Scheme