in benzene 24 h; Heating;

1: 79 percent / sodium methylsulfinyl carbanion / dimethylsulfoxide / 10 °C 3: 94 percent / imidazole / dimethylformamide / 4 h / 25 °C 4: 1.) n-butyllithium, 2.) Gilman reagent, cuprrous cyanide, HMPA 5: H2, triethylamine / Lindlar catalyst / hexane / 760 Torr 6: tetra-n-butylammonium fluoride / tetrahydrofuran / 25 °C 7: 25 °C / saponification View Scheme