[Li(tmeda)2][cyclo-(P5But4)]: An unusual ion-separated lithium oligophosphanide

The unusual coordination chemistry of phosphorus-rich linear and cyclic oligophosphanide anions

“…An analogous reaction between the less reactive [K 2 (pmdeta) 2 (P 4 Ph 4 )] (36) and [Ni(cod) 2 ] (ratio 1:1 or 2:1) gave as a major product the complex [K(pmdeta)] 2 [Ni(P 4 Ph 4 )( 2 -P 2 Ph 2 )] (63) (Scheme 22), and provided some insight into the mechanism of formation of 62 (Scheme 23). Complex 63 can be considered to be the potassium analogue of the intermediate species in the formation of 62; however, in the case of potassium, the K-Ni and K-P interactions stabilize the NiP 4 framework and prevent further reaction to give the corresponding potassium Both complexes were characterized by single-crystal X-ray diffraction studies.…”

“…The targeted synthesis of anionic ring systems such as M[cyclo-(P 5 R 4 )] (M = Li, Na or K; R = Pr i , Bu t , Ph) has been reported [36,37,41]. These compounds have been synthesized by the reaction of lithium, sodium or potassium with the corresponding RPCl 2 and PCl 3 in the ratio 12:4:1 in THF (Scheme 11).…”

“…5). The lithium cation is coordinated in a usual distorted tetrahedral fashion by four nitrogen atoms of two TMEDA molecules, which prevents interaction of the cation with the anion and thus results in a "naked" [cyclo-(P 5 Bu t 4 )] − anion (Li(1)· · ·P(1) 494.0(6) pm) [36]. This type of anionic two-coordinate phosphorus atom is typical in metal complexes of white phosphorus [42], but rare for linear or cyclic oligophosphanides [43].…”