Several new indolyl secondary phosphine oxides (SPOs), C 8 H 6 N–P(O)(H)( t Bu) (4a′), MeC 8 H 5 N–P(O)(H)( t Bu) (4b′), and PhC 8 H 5 N–P(O)(H)( t Bu) (4c′), were prepared from the reactions of corresponding 1H-indoles with P t BuCl 2 and hydrolysis followed. Further reaction of 4a′, a tautomeric form of C 8 H 6 N–P(OH)( t Bu) (4a), with Pd(COD)Cl 2 yielded a di-palladium complex, [(4a)(4a-H + )Pd(μ-Cl)] 2 (6a). Crystal structures of PhC 8 H 5 N–P(Cl)( t Bu) (3c), (4c′) and (6a) were determined by single-crystal X-ray diffraction methods. The stability of this type of SPO is presumably caused by the indolyl scaffold. In addition, SPOs are air- and moisture-stable preligands and are advantageous for the purpose of storage. In this work, these SPO ligands were employed in the Suzuki–Miyaura cross-coupling reactions as catalytic precursors. This catalytic condition has been tolerated to a variety of functional groups and the coupling reactions underwent efficiently with the arylbromides and arylchlorides, respectively.