Hemilabile ligands attracted much attention in past thirty years because they were effectively utilized in the field of coordination chemistry and homogenous catalysis. We have synthesized four tridentate iminophosphine ligands (o-Ph2P(C6H4)-C(H)=N-(CH2)n-R, n = 2, R = SnBu, LPNS1; n = 3, R = SMe, LPNS2; n = 3, R = OMe, LPNO3; and n = 3, R = NMe2, LPNN4) and one tridentate aminophosphine ligand (o-Ph2P(C6H4)CH2N(H)(CH2)3NMe2, LPNHN5) in this work. The structures of the iminophosphine copper(I) complexes were determined by the carbon-chain length between imino-nitrogen and third donor atom, the coordination ability of the third donor atom, and the nature of the anions (i.e. its donor ability and atomic radius). An unexpected tetranuclear copper(I) iodide complex [(CuI)2(LPNN4)]2 (16) was obtained due to the larger atomic radius of iodide ion. The ligand LPNN4 displayed versatile coordination behavior after complexing with some late transition metals such as Pd(II), Ag(I), Zn(II), Cd(II). These tridentate ligands may act as PN-chelator or PNE-chelator (E = S, N¡¦). Both chelating and bridging modes were observed at the same time in Cu(I) and Ag(I) complexes. In Zn(II) complex, however, chelating by LPNN4 chelated only occurred through its N donor atoms. In term of the reactivity study of these complexes, we found that the complex [Cu(LPNN4)(CH3CN)0.2](BF4) (17) would successful react with Na(SCN), NaN3, and PhCCH/KOH to generate corresponding substitution products. However when reacted with PhCCC(O)OH/KOH, copper complexes bearing LPNN4 could not give the corresponding substituted carboxylate copper(I) product and gave the complex [Cu(CCPh)(LPNN4)]2 (18) via auto-decarboxylation instead.