Yield given. Multistep reaction;

1: {1-[chloro(p-tolylsulfinyl)methyl]cyclopentadecyl}acetonitrile With lithium diisopropyl amide in tetrahydrofuran T=-78°C; 0.5 h; 2: lithium α-carbanion of propionitrile in tetrahydrofuran T=-78 - 20°C; 2.5 h;