2,6-Dichlorobenzaldehyde → Benzene, 1,3-dichloro-2-ethynyl-

Participants

Reaction Steps

To a mixture of tosyl azide (2.70 g, 32 mmol) and K2CO3 (4.74 g, 34.3 mmol) in dry acetonitrile (20 mL) was added dropwise a solution of dimethyl 2-(oxopropyl)-phosphonate (1.89 mL, 2.27 g, 13.7 mmol) in acetonitrile (5 mL) then the mixture was stirred at ambient temperature for 3 h. To this mixture was added dropwise a solution of 2,6-dichlorobenzaldehyde (2.0 g, 11.4 mmol) in methanol (15 mL), and the resulting mixture stirred at ambient temperature for 18 h. The solvent was removed under reduced pressure, and the residue stirred with ethyl acetate and sat. ammonium chloride. This mixture was filtered to remove insolubles, and the filtrate separated. The aqueous phase was re-extracted with ethyl acetate, and the combined organic layers were dried, filtered, and the was solvent removed under reduced pressure. The residue was purified by chromatography using a gradient of 0-20% hexane/ethyl acetate to afford 2,6-dichlorophenylacetylene.

Provenance & Evidence