Compounds containing this functional group are treated with iodine and either silver benzoate or silver acetate in the Prevost and Woodward reactions, respectively. Cobalt coordinated to four carbonyl ligands is used to convert instances of this functional group into aldehydes. In the presence of a chiral quinine ligand, this functional group reacts with osmium tetroxide to form (10[2])diols in an asymmetric (-5[1])reaction (10[1])named for Sharpless. This nucleophilic functional group (-5[1])displaces an acetoxy group after attacking mercury in the first step of an alcohol-forming reaction used to prevent rearrangements. Treating this functional group with borane in THF yields the anti-Markovnikov product. A solution of bromine is often used to detect this functional group. For 10 points, name this functional group in which two carbons are joined by a double bond. (10[2])■END■ (10[2]0[3])