“…The crude product was recrystallized from chloroform to give white crystals of hydrazide 5 (8.5 g, 85%, mp 71-72 °C). The analytical sample was prepared by further recrystallization from chloroform: mp 72.5-73.5 °C (lit.13 76-78 °C); MS, m/e 130 (M+); NMR (CDC13) 0.88 (m, 3, CH3), 2.2 (m, 2, CCH2), 4.0 (br s, 2, NH2), 8.0 (br s, 1, NH). Anal.…”