“…Effective and widely used procedures are (i) the corrosive pretreatment of Raney Ni, 55,76,300,306 (ii) prereduction of supported Pt 143,203,293 and Pd 69,391,395,464 in hydrogen at elevated temperature in the gas phase or in solution, and (iii) ultrasonication of Pt, 56,[465][466][467] Pd, 347,369 and Ni [468][469][470] in solution in the presence of the modifier. These empirically developed techniques are highly catalyst specific.…”