Reacción #68014

Ecuación de reacción

6-bromo-2,3-dihydro-1,4-benzodithiin

butyllithium hexane

hydrochloric acid

ethyl formate

→

2,3-dihydro-1,4-benzodithiin-6-carbaldehyde

Disolventes

tetrahydrofuran

ethyl acetate

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONwas added at −78° C.
2. 2
   workup.STIRRINGthe mixture was further stirred for 2 hours
3. 3
   workup.ADDITIONwas then added to the mixture
4. 4
   OtroThe organic layer was separated
5. 5
   Lavadowashed with an aqueous saturated sodium hydrogen carbonate solution
6. 6
   Secadodried over anhydrous magnesium sulfate
7. 7
   Otrothe solvent was removed under reduced pressure
8. 8
   OtroThe residue thus obtained
9. 9
   Otrowas purified by silica gel column chromatography [silica gel; Silica gel 60N manufactured by Kanto Chemical Co., Inc., eluent; ethyl acetate:hexane 1:4]

Procedimiento

To 5 mL of a tetrahydrofuran solution containing 500 mg of 6-bromo-2,3-dihydro-1,4-benzodithiin, 0.67 mL of a 2.67 mol/L butyllithium/hexane was added at −78° C., the mixture was stirred for 0.5 hour, then 300 mg of ethyl formate was added thereto, and the mixture was further stirred for 2 hours. Thereto was added 1 mol/L hydrochloric acid, and ethyl acetate was then added to the mixture. The organic layer was separated, washed with an aqueous saturated sodium hydrogen carbonate solution and dried over anhydrous magnesium sulfate, and the solvent was removed under reduced pressure. The residue thus obtained was purified by silica gel column chromatography [silica gel; Silica gel 60N manufactured by Kanto Chemical Co., Inc., eluent; ethyl acetate:hexane 1:4] to obtain 121 mg of a brown oily substance, 2,3-dihydro-1,4-benzodithiin-6-carbaldehyde.

Fuente