1: 62 percent / sodium azide / H2O; dimethylformamide 2: 56 percent / camphorsulphonic acid / methanol; H2O 3: 95 percent / barium methoxide / methanol 5: tetrahydrofuran 6: 80 percent / hydrogen / palladium on carbon / ethanol 7: 92 percent / sodium methoxide / methanol 8: 1.) borane, dimethyl sulphide; 2.) aq. trifluoroacetic acid View Scheme