To a solution of 1-(diphenylmethylamino)-3-chloro-2-propanol (Intermediate 32, 276 g, 1 mol) in ethanol (2 L) was slowly added N,N-diisopropylethylamine (DIPEA, 129 g, 1 mol) at 0 °C. Subsequently, the reaction mixture was heated to 90 °C and refluxed overnight. Upon completion of the reaction, the solvent was removed by distillation under reduced pressure to afford the crude product 1-diphenylmethyl-3-hydroxyazetidine (179 g, 75% yield). The product can be purified by recrystallization from a solvent mixture of acetone and petroleum ether.
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[4] Synthesis (Germany), 2018, vol. 50, # 5, p. 1020 - 1026
