This species serves as a ligand in an oddly nonacoordinated potassium rhenium salt. After migratory insertion of a carbonyl, one of these ligands is transferred to the product of the oxo process during its release from the catalyst. (-5[1])A mechanism that converts an alkyl group into a coordinated alkene transfers one of these ligands from a beta carbon to a metal center. Two of these ligands bridge a pair of (*) aluminum centers in DIBAL. This species (10[1])is the smallest substituent that can move in a 1,2-migration. (10[1]-5[1])This species’ Pauling electronegativity of -2.2 leads it to form nonpolar bonds with carbon. (10[1])For 10 points, name (10[1])this species that complicates electron counting schemes due to filling its outer orbital with only two electrons. (10[1])■END■ (10[3]0[5])