To a solution of cyclobutanone 6 (300.0 g, 2.34 mol) in MeOH (2.5 L) neat benzyl amine (263.3 g, 2.46 mol) was added in one portion and the mixture was stirred for 2 h at rt. The resulting solution was cooled to -10 °C in a NaCl/ice bath, and neat TMSCN (464.3 g, 4.68 mol) was added in a dropwise manner at the same temperature. After addition, the bath was removed, and the reaction mixture was left with stirring overnight. The volatiles were removed under reduced pressure and the oily residue was purified by flash column chromatography (hexanes -EtOAc, gradient 1:1 to 1:2 v/v). The major diastereomer 7 was isolated by trituration of the purified mixture with minimum amounts of 2-propanol (dr ca. 92:8). Yield 366.0 g, 1.50 mol, 64%.