Diisopropylamine → Methyl 5-(2,5-Dichlorophenyl)pentanoate

Participants

Reaction Conditions

Reaction Steps

Diisopropylamine (841 μl, 6 mmol) was added to 20 mL of THF under nitrogen atmosphere and cooled to 0° C. 5.5 ml of 2.5 N n-butyllithium (55.5 mmol) was added and the reaction was stirred for 20 minutes. The reaction was then cooled to −78° C. 2,5-Dichlorotoluene (642 μL, 5 mmol) was added and stirring was continued for 2 hours at −78° C. Trimethyl 4-bromoorthobutyrate (1.14 g, 5 mmol) was added to the reaction mixture in 10 mL THF. The reaction was stirred for 5 minutes at −78° C., allowed to come to room temperature and stirred overnight. The reaction was worked-up by adding 10 mL of saturated KH2PO4, removal of most of the THF on a rotary evaporator followed by partitioning of the aqueous residue between ethyl acetate and 1 N HCl. The organic phase was washed twice with 1 N HCl, once with 5% NaHCO3, dried over sodium sulfate and concentrated to a residue. Flash chromatography (silica gel; hexane/toluene (39/1)) of the residue gave 1.10 g (84%; GC retention time=15.80 minutes) of a water white oil

Provenance & Evidence