Two iodo derivatives, [closo-B10H9-1-I](2-) (1) and [closo-B10H8-1,10-I-2](2-) (2), were obtained from the parent [closo-B10H10](2-) anion in a two-step process and about 60% and 80% overall yields, respectively. Molecular and crystal structures of 2[Pr4N] were established with XRD methods: I422; a = b = 10.1531(1) angstrom, c = 18.0149(2) angstrom; alpha = beta = gamma = 90 degrees; Z = 2. Synthetic applications of 1[Bu4N] were demonstrated in a Pd(0)-catalyzed cross-coupling reaction with 4-MeOC6H4MgBr.