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To a mixture of lithium chloride (0.55 g, 13 mmol) and magnesium turnings (0.63 g, 26 mmol) in dry tetrahydrofuran (34 ml) was added 1M diisobutyl aluminum hydride solution in tetrahydrofuran (0.10 ml, 0.10 mmol) at room temperature. After stirring for 5 minutes a solution of 3-bromo-2-chloro-pyridine (2.00 g, 10.4 mmol) in dry tetrahydrofuran (1 ml) was added at 0-5° C. Stirring for 1 h was followed by addition of a solution of zinc chloride (1.42 g, 10.4 mmol), which had previously been dried by melting in vacuo followed by cooling under argon, in dry tetrahydrofuran (10 ml). After stirring for 1 h the mixture was decanted into another flask by cannulation under argon. Addition of tetrakis(triphenylphosphine)palladium(0) (0.59 g, 0.51 mmol) and trans-4-chlorocarbonyl-cyclohexanecarboxylic acid methyl ester (2.10 g, 10.3 mmol) was followed by stirring at room temperature for 18 h. The mixture was partitioned between ethyl acetate (150 ml) and 0.1M aqueous hydrogen chloride solution (100 ml). The layers were separated. The aqueous layer was extracted with two 100-ml portions of ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate and concentrated to dryness. Purification by flash-chromatography with n-heptane/tert-butyl methyl ether as eluent gave the title compound (1.3 g, 46%) as yellow solid. MS m/e: 282 ([M+H]+)

1. additionwas added at 0-5° C
2. customhad previously been dried
3. temperatureby cooling under argon, in dry tetrahydrofuran (10 ml)
4. stirringAfter stirring for 1 h the mixture
5. customwas decanted into another flask by cannulation under argon
6. stirringby stirring at room temperature for 18 h
7. customThe mixture was partitioned between ethyl acetate (150 ml) and 0.1M aqueous hydrogen chloride solution (100 ml)
8. customThe layers were separated
9. extractionThe aqueous layer was extracted with two 100-ml portions of ethyl acetate
10. dry with materialThe combined organic layers were dried over anhydrous sodium sulfate
11. concentrationconcentrated to dryness
12. customPurification by flash-chromatography with n-heptane/tert-butyl methyl ether as eluent