Dimethylformamide → 4,4-dimethyl-3,4-dihydro-2H-thiochromene-6-carbaldehyde

Participants

Reaction Steps

9.4 g (36.6 mmol) of 4,4-dimethyl-6-bromothiochroman and 100 ml of THF were introduced into a three-necked flask under a stream of nitrogen. 16.1 ml of an n-butyllithium solution (2.5M in hexane) were added dropwise at −78° C. and stirring was carried out for 30 min. 2.7 ml (38.4 mmol) of DMF were then added dropwise and the mixture was permitted to heat to room temperature. The reaction mixture was poured into an aqueous ammonium chloride solution and extracted with ethyl ether. The organic phase was separated by settling, dried over magnesium sulfate and evaporated. The residue obtained was purified by chromatography on a silica column eluted with a mixture of dichloromethane and hexane (50/50). After evaporating the solvents, 6.1 g (81%) of the expected aldehyde were recovered in the form of a yellow oil.

Provenance & Evidence