In one reaction, a pi-allyl complex containing this element undergoes a Walden inversion in an oxidative addition step that allows a nucleophile to substitute an alkene. Barium sulfate poisons this element (15[3])in a (15[1])reduction reaction (15[1])that produces (15[3])aldehydes. Reducing an acetate with phosphine activates this element in one reaction, and this element is regenerated by copper (15[1])chloride to catalyze the oxidation (15[1])of ethylene (-5[1])into acetaldehyde (15[1])during the (*) Wacker process. (10[1])This element catalyzes a reaction that forms carbon-carbon bonds with an organoboron (10[2])species (10[1]-5[1])and a halide. Heck, Negishi, (10[1])and (10[1])Suzuki (10[1])won the 2010 (10[2])Nobel (10[4])Prize (-5[1])in (-5[1])Chemistry for work on cross-coupling (-5[1])reactions (10[1])catalyzed (10[1])by this metal. (-5[2])For 10 points, (10[1])name (10[1])this expensive platinum-group metal (10[1]-5[2])found (10[1]-5[1])in Lindlar’s catalyst, (10[1])with symbol Pd. (10[1])■END■ (10[13]0[1])