Synthesis and Reactions of Alkali Metal Derivatives of the Ph4P2N4S2(2-) Dianion: X-ray Structure of Cp(*)Rh(η3-Ph4P2N4S2-N,S,S')

Article abstract of DOI:10.1021/ic00124a019

The reaction of 1,5-Ph4P2N4S2 with 2 molar equiv of M[BEt3H] in THF produces {M2[Ph4P2N4S2]}n (4a, M = Li; 4b, M = Na; 4c, M = K) in quantitative yields with the concomitant evolution of H2 gas. The lithium and sodium derivatives are obtained as insoluble, yellow powders, whereas {K2[Ph4P2N4S2]}n (δ((31)P) = 33.5 ppm) is soluble in THF when formed initially. The reaction of {Na2[Ph4P2N4S2]}n with CH2I2 in THF yields Ph4P2N4S2CH2 (5a) in excellent yields. The methylene-bridged compound 5a is readily deprotonated by LiN(SiMe3)2 in THF, and the subsequent addition of MeI produces Ph4P2N4S2CHMe (5b). In a similar way, 5b can be deprotonated and methylated to give Ph4P2N4S2CMe2. The reaction of {Na2[Ph4P2N4S2]}n with (Cp(*)RhCl2)2 in THF affords Cp(*)Rh(Ph4P2N4S2) (6), which can also be produced by the oxidative addition of 1,5-Ph4P2N4S2 to Cp(*)Rh(C2H4)2. The X-ray structure of 6 reveals that the heterocyclic P2N4S2 ligand is bonded to Rh in a tridentate (η3-N,S,S') fashion with d(Rh-N)= 2.135(5) ?. Crystals of 6 are triclinic, space group P1- with a =10.167(1) ?, b = 17.972(2) ?, c = 9.377(1) ?, α = 100.24(1)°, β = 93.19(1)°, γ = 95.35(1)°, V= 1674.2(3) ?**3, and Z = 2. The final R and Rw values were 0.045 and 0.058, respectively. The treatment of {M2[Ph4P2N4S2]}n with a varietyof other electrophiles, e.g. ICH2CH2I, PhCHBr2, CHI3, CBr4, Me2SiCl2, Me2SnCl2, PhPCl2, S2Cl2, GeCl4, or FeBr2, regenerates the folded ring system 1,5-Ph4P2N4S2.