Sodium Dithionite → (2S)-1-(2,3-Diaminophenoxy)-3-(dibenzylamino)propan-2-ol

Participants

Reaction Steps

(S)-[3-(N,N-Dibenzylamino)-2-hydroxypropoxy]-2-amino-3-nitrobenzene (10.6 g, 26.0 mmol) was suspended in 1 L of 2:1 ethanol/water at ambient temperature and treated with excesses of sodium bicarbonate (26.22 g, 0.31 mol) and sodium hydrosulfite (54.34 g, 0.31 mol). The orange reaction mixture slowly became colorless over 1 hour, and the mixture was left to stir at ambient temperature for 16 hours. The suspension was filtered, and the filtrate concentrated in vacuo to a leave a white solid. This residue was partitioned between chloroform and water, and the organic layer washed twice with brine. The combined organic extracts were concentrated in vacuo to give 8.8 g of a brown oil. The compound was recrystallized rapidly from toluene to give 7.96 g (81%) of pale brown needles. NMR.

Provenance & Evidence