Diisopropylethylamine → 1-Benzhydryl-5-bromo-1H-indole-2-carboxylic Acid

Participants

Reaction Conditions

Reaction Steps

To 5-bromoindole-2-carboxylic acid (1.024 g, 4.26 mmol) in 1-methyl-2-pyrrolidinone (13 mL) at 0° C. were added iPr2NEt (25.6 mmol), tetrabutylammonium iodide (157 mg, 0.426 mmol) and bromodiphenylmethane (1.20 g, 4.86 mmol). The reaction mixture was heated at 50° C. for 21 h before partitioning between diethyl ether and ice water. After adjusting the pH to 3, the aqueous layer was extracted with diethyl ether. The organic layers were combined, washed with NaH2PO4, dried over MgSO4 and evaporated to dryness. Purification on silica gel column (15% EtOAc in hexane) yielded 1.51 g (87% yield) of the product.

Provenance & Evidence