1: 1.) dibutyltin oxide, 2.) tetrabutylammonium iodide / 1.) benzene, reflux, 16 h, 2.) reflux, 4 h 2: 1.) dibutyltin oxide, 2.) tetrabutylammonium iodide / 1.) benzene, reflux, 16 h, 2.) reflux, 28 h View Scheme

tetra-(n-butyl)ammonium iodide; di(n-butyl)tin oxide 1.) benzene, reflux, 16 h, 2.) reflux, 4 h; Yield given. Multistep reaction;