Chlorotrimethylsilane → HCID 20528946, compound

Temperature

80 °C

To a suspension of zinc dust (2.00 g, 30.6 mmol) in N,N-dimethylacetamide (20 mL) was added a mixture of trimethylsilyl chloride and 1,2-dibromoethane (7:5, v/v, 0.95 mL total volume) dropwise over 5 minutes. The mixture was stirred for 15 min before cyclopentyl iodide (5.00 g, 25.5 mmol) was added dropwise over 15 min. This mixture was stirred for an additional 15 min and then was added via syringe over 5 min to a mixture of copper(I) iodide (0.30 g, 1.60 mmol), dichloro(1,1-bis(diphenylphosphinoferrocene))palladium(II) (0.65 g, 0.80 mmol), and 2,3-dichloropyrazine (1.66 mL, 16.0 mmol) in N,N-dimethylacetamide (30 mL) under argon atmosphere. The mixture was heated to 80° C. for 7 h, cooled to room temperature and partitioned between ethyl acetate and saturated aqueous ammonium chloride. The resulting layers were separated and the aqueous layer was extracted with ethyl acetate (1×). The combined extracts were washed with water (2×), saturated aqueous sodium chloride (1×), dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. The residue was purified by silica gel chromatography to give 2-chloro-3-cyclopentylpyrazine.

1. additionwas added
2. additionwas added dropwise over 15 min
3. temperaturecooled to room temperature
4. custompartitioned between ethyl acetate and saturated aqueous ammonium chloride
5. customThe resulting layers were separated
6. extractionthe aqueous layer was extracted with ethyl acetate (1×)
7. washThe combined extracts were washed with water (2×), saturated aqueous sodium chloride (1×)
8. dry with materialdried over anhydrous magnesium sulfate
9. filtrationfiltered
10. concentrationconcentrated in vacuo
11. customThe residue was purified by silica gel chromatography

ORD record

ord-74a7c0aa1a374b25ae4dda7ecf9d308e

Source dataset

uspto-grants-2011_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08053438B2