1.1: sodium hydrogencarbonate / methanol / 3 h / |Reflux 2.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / water; butan-1-ol / 12 h / |Reflux 3.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / methanol; water / 0.5 h / |Reflux 3.2: 12 h / 40 °C 4.1: L-CSA*1H2O / toluene / 49 h / 20 - 50 °C / |Resolution of racemate 4.2: 6 h / |Resolution of racemate; |Reflux View Scheme

1.1: sodium hydrogencarbonate / methanol / 3 h / |Reflux; |Green chemistry 2.1: N-benzyl-N,N,N-triethylammonium chloride; sodium hydroxide / water; butan-1-ol / 12 h / |Reflux; |Green chemistry 3.1: N-benzyl-N,N,N-triethylammonium chloride; sodium hydroxide / methanol; water / 0.5 h / 10 - 40 °C / |Reflux; |Green chemistry 3.2: 12 h / 40 °C / |Green chemistry 4.1: (-)-10-CSA / water; toluene / 49 h / 20 - 50 °C / |Green chemistry 5.1: sulfuric acid / 12 h / 0 °C / |Green chemistry View Scheme

1.1: sodium hydrogencarbonate / methanol / 3 h / |Reflux 2.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / water; butan-1-ol / 12 h / |Reflux 3.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / methanol; water / 0.5 h / |Reflux 3.2: 12 h / 40 °C View Scheme

sodium hydrogencarbonate in methanol 3 h; Reflux;

sodium hydrogencarbonate in methanol 3 h; Heating / reflux; Product distribution / selectivity;

Multi-step reaction with 5 steps 1.1: sodium hydrogencarbonate / methanol / 3 h / |Reflux2.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / water; butan-1-ol / 12 h / |Reflux3.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / methanol; water / 0.5 h / |Reflux3.2: 12 h / 40 °C4.1: L-CSA*1H2O / toluene / 49 h / 20 - 50 °C / |Resolution of racemate4.2: 6 h / |Resolution of racemate; |Reflux5.1: |Enzymatic reaction