4-Methylmorpholine → Benzophenone

Participants

Reaction Conditions

Reaction Steps

The D-biotin (50 mg, 2.05 mmol) is solubilized in 23 ml of anhydrous DMF in the hot state. The mixture is cooled to 0° C. under argon, and then N-methylmorpholine (295 μl, 2.67 mmol) and isobutyl chloroformate (420 μl, 3.28 mmol) are successively added. The mixture is kept stirred for 30 min, and then 3-aminobenzophenone (605 mg, 3.07 mmol) and N-methylmorpholine (240 μl, 2.17 mmol) in 7 ml of DMF are added. The solution is maintained stirred at 0° C. for 2 h, and then evaporated to dryness. The residue is taken up in 1 ml of MeOH, and then 25 ml of water are added. The precipitate obtained is filtered, washed with water and then with ether to give 810 mg (93%) of crude product 1d. Recrystallization from the MeOH—H2O pair gives 1d (630 mg, 72%) in the form of a white powder.

Provenance & Evidence