Tributylstannane → Tert-butyl 7-methoxy-1,3a,4,9b-tetrahydrochromeno[3,4-b]pyrrole-3(2H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

Tert-butyl 2-[(2-bromo-5-methoxyphenoxy)methyl]-2,5-dihydro-1H-pyrrole-1-carboxylate (16.4 g, 0.43 mol) was dissolved in toluene (790 mL) and heated at 50° C. for 20 min. To this solution was added AlBN (781 mg, 0.047 mol) and tributyltin hydride (17.9 mL, 0.67 mol). The reaction mixture was stirred at 80° C. for 16 h, cooled to RT, and DBU (10.7 g, 0.70 mol) was added. The resulting suspension was filtered through a pad of silica gel (100 g), and the solids washed with methyl tert-butylether. The filtrate was evaporated and the resulting oil triturated with heptane (10 mL). The crude product was collected via filtration and purified using an ISCO instrument (330 g RediSep® column), eluting with a gradient of ethyl acetate in heptane (from 5%-20%) to afford the title product. MS m/z 249 [M−tBu+H]+

Provenance & Evidence