4-(2-tert-Butyl-5-nitro-phenyl)-but-3-enal (895 mg) was dissolved in 40 mL THF, and to the solution was added pyrrolidine (0.317 mL). To the deep-orange solution was added NaBH(OAc)3 (1.151 g) and glacial AcOH (0.207 mL). The reaction was stirred at RT overnight, then treated with saturated aqueous NaHCO3 and diluted with Et2O and some 1 N NaOH. The layers were separated, and the organic layer was extracted with aqueous 2 N HCl. The acidic aqueous layer was basified to pH>12 with 6 N NaOH, extracted with Et2O, brine-washed, dried over Na2SO4, filtered, and concentrated in vacuo to provide 1-[4-(2-tert-butyl-5-nitro-phenyl)-but-3-enyl]-pyrrolidine as a orange-brown oil.
