1: 96 percent / (S)-α,α-diphenylprolinol - n-butylboronic acid, catecholborane / toluene / 56 h / -20 °C 2: 80 percent / NaN3, NaOH, H2O / 1,2-dimethoxy-ethane / 24 h / 23 °C 3: H2 / 10percent Pd/C / ethyl acetate / 13 h / 760 Torr View Scheme

sodium dichromate; sulfuric acid; acetic acid

1: 76 percent / sodium trichloroacetate / dimethylformamide / 9 h / 23 °C 2: 100 percent / Na2Cr2O7, H2SO4, glacial acetic acid View Scheme

P=20 Torr; Heating;

chlorine in tetrachloromethane 1 h; Irradiation;