1: caustic lye / 12 h / 120 °C 2: sodium hydroxide / methanol / 1 h / 25 °C View Scheme

1.1: toluene; tetrahydrofuran / 2 h / 0 °C 2.1: palladium diacetate; triphenylphosphine; triethylamine / toluene / 12 h / 100 °C / |Inert atmosphere 3.1: B-chloro-diisopinocampheylborane / dichloromethane; n-heptane / 8 h / 25 °C 4.1: toluene; tetrahydrofuran / 4 h / 0 - 5 °C 5.1: N-ethyl-N,N-diisopropylamine / dichloromethane / -20 - -15 °C / |Inert atmosphere 6.1: n-butyllithium / tetrahydrofuran / 0.5 h / -15 °C / |Inert atmosphere 6.2: 5.5 h / -15 - -5 °C / |Inert atmosphere 7.1: palladium diacetate; triphenylphosphine; triethylamine / N,N-dimethyl-formamide / 110 °C 8.1: caustic lye / 12 h / 120 °C 9.1: sodium hydroxide / methanol / 1 h / 25 °C View Scheme

1.1: B-chloro-diisopinocampheylborane / dichloromethane; n-heptane / 8 h / 25 °C 2.1: toluene; tetrahydrofuran / 4 h / 0 - 5 °C 3.1: N-ethyl-N,N-diisopropylamine / dichloromethane / -20 - -15 °C / |Inert atmosphere 4.1: n-butyllithium / tetrahydrofuran / 0.5 h / -15 °C / |Inert atmosphere 4.2: 5.5 h / -15 - -5 °C / |Inert atmosphere 5.1: palladium diacetate; triphenylphosphine; triethylamine / N,N-dimethyl-formamide / 110 °C 6.1: caustic lye / 12 h / 120 °C 7.1: sodium hydroxide / methanol / 1 h / 25 °C View Scheme

1.1: tetrahydrofuran; hexane / 10 h / -15 - 5 °C 1.2: 24 h / 25 - 35 °C 2.1: acetic acid / dichloromethane; water / 25 - 30 °C / pH 4 - 4.5 2.2: 0.5 h View Scheme

Product distribution / selectivity;

Product distribution / selectivity;

hydrogenchloride in water T=20 - 25°C; 1 h;

hydrogenchloride in water; isopropyl alcohol T=20°C; 0.916667 h;

1: 1-(mercaptomethyl)-cyclopropaneacetic acid With sodium t-butanolate; PEG-600 in toluene Inert atmosphere; 2: montelukast sodium salt in tetrahydrofuran; toluene T=20°C; Inert atmosphere;