The reaction of 1,5-Ph(4)P(2)N(4)S(2) with 2 molar equiv of M[BEt(3)H] in THF produces {M(2)[Ph(4)P(2)N(4)S(2)]}(n) (4a, M = Li; 4b, M = Na; 4c, M = K) in quantitative yields with the concomitant evolution of H-2 gas. The lithium and sodium derivatives are obtained as insoluble, yellow powders, whereas {K-2[Ph(4)P(2)N(4)S(2)]}(n)(delta(P-31) = 33.5 ppm) is soluble in THF when formed initially. The reaction of {Na-2[Ph(4)P(2)N(4)S(2)]}(n) with CH2I2 in THF yields Ph(4)P(2)N(4)S(2)CH(2) (5a) in excellent yields. The methylene-bridged compound 5a is readily deprotonated by LiN(SiMe(3))(2) in THF, and the subsequent addition of MeI produces Ph(4)P(2)N(4)S(2)CHMe (5b). In a similar way, 5b can be deprotonated and methylated to give Ph(4)P(2)N(4)S(2)CMe(2). The reaction of {Na-2[Ph(4)P(2)N(4)S(2)]}(n) with (Cp(*)RhCl(2))(2) in THF affords Cp(*)Rh(Ph(4)P(2)N(4)S(2)) (6), which can also be produced by the oxidative addition of 1,5-Ph(4)P(2)N(4)S(2) to Cp(*)Rh(C2H4)(2). The X-ray structure of 6 reveals that the heterocyclic P2N4S2 ligand is bonded to Rh in a tridentate (eta(3)-N,S,S’) fashion with d(Rh-N) = 2.135(5) Angstrom. Crystals of 6 are triclinic, space group P (1) over bar with a = 10.167(1) Angstrom, b = 17.972(2) Angstrom, c = 9.377(1) Angstrom, alpha = 100.24(1)degrees, beta = 93.19(1)degrees, gamma = 95.35(1)degrees, V = 1674.2(3) Angstrom(3), and Z = 2. The final R and R(w) values were 0.045 and 0.058, respectively. The treatment of {M(2)[Ph(4)P(2)N(4)S(2)]}(n) with a variety of other electrophiles, e.g. ICH2CH2I, PhCHBr(2), CHI3, CBr4, Me(2)SiCl(2), Me(2)SnCl(2), PhPCl(2), S2Cl2, GeCl4, or FeBr2, regenerates the folded ring system 1,5-Ph(4)P(2)N(4)S(2).