Dichloromethane → 2,5-Dihydro-3,6-dimethoxy-2-isopropyl-5-(2'-iodo-4'-hydroxy-5'-formylbenzyl)-(2R,5S)-pyrazine

Participants

Reaction Conditions

Reaction Steps

A 1M solution of BCl3 in dichloromethane (11.8 mL, 11.8 mmol) was added drop wise to a solution of the methoxybenzyl pyrazine analog 22 (134.80 mg, 0.30 mmol) and stirred at 0° C. under argon. The solution changed in color from the initial orange to light brown and finally to greenish brown. The reaction mixture was stirred for one hour at 0° C. and warmed slowly to room temperature over night. The reaction mixture was poured into ice-water and stirred for 15 min. The mixture was extracted with dichloromethane and the organic phase was dried with Na2SO4. Evaporation of the solvent gave a yellow brown oil which upon flash chromatographic purification provided pure 2,5-dihydro-3,6-dimethoxy-2-isopropyl-5-(2′-iodo-4′-hydroxy-5′-formylbenzyl)-(2R,5S)-pyrazine (24) (41.40 mg, 32%).

Provenance & Evidence