1.1: methanol / 2.5 h / 60 °C / |Inert atmosphere 2.1: sodium tetrahydroborate / methanol / 0.5 h / 20 °C / |Inert atmosphere 3.1: hydrogenchloride; water / acetone / 0.17 h / 20 °C / |Inert atmosphere 4.1: sodium tetrahydroborate / ethanol / 0 °C 5.1: 1H-imidazole / N,N-dimethyl-formamide / 20 °C 6.1: bromine / dichloromethane / -78 °C 6.2: |Reflux 7.1: oxalyl dichloride / dichloromethane; dimethyl sulfoxide / 1 h / -78 °C / |Inert atmosphere 7.2: -78 °C / |Inert atmosphere; |Enzymatic reaction 8.1: tris-(dibenzylideneacetone)dipalladium(0); 2,2'-bis-(diphenylphosphino)-1,1'- binaphthyl; sodium t-butanolate / toluene / 100 °C / |Inert atmosphere View Scheme

1.1: hydrogenchloride; water / acetone / 0.17 h / 20 °C / |Inert atmosphere 2.1: sodium tetrahydroborate / ethanol / 0 °C 3.1: 1H-imidazole / N,N-dimethyl-formamide / 20 °C 4.1: bromine / dichloromethane / -78 °C 4.2: |Reflux 5.1: oxalyl dichloride / dichloromethane; dimethyl sulfoxide / 1 h / -78 °C / |Inert atmosphere 5.2: -78 °C / |Inert atmosphere; |Enzymatic reaction 6.1: tris-(dibenzylideneacetone)dipalladium(0); 2,2'-bis-(diphenylphosphino)-1,1'- binaphthyl; sodium t-butanolate / toluene / 100 °C / |Inert atmosphere View Scheme

sodium tetrahydroborate 1.) MeOH, reflux, 3 h, 2.) MeOH, 0 deg C, 30 min; Multistep reaction;

1: pyridine / 1.5 h / 0 °C 2: 2 percent / PhI(COCF3)2 / various solvent(s) / 1.5 h / -40 °C View Scheme