“…1b) and thus results in a ''naked'' [cyclo-(P 5 Bu t 4 )] À anion (Li(1)Á Á ÁP(1) 494.0(6) pm). This type of anionic twocoordinate phosphorus atom is typical in metal complexes of white phosphorus (see for example [13] and references therein), but rare for linear or cyclic oligophosphanides [2,3,7,9,14]. Only a few examples display an ion-separated structure, such as [K(18-crown-6)(thf) 2 ][P 4 HMes 4 ] (Mes = 2,4,6-Me 3 C 6 H 2 ), in which the potassium cation is coordinated by 18-crown-6 and two THF molecules [3a], Table 1 Comparison of simulated 31 P{ 1 H} NMR data for M[cyclo-(P 5 Bu t 4 )] (M = Li, Na, K).…”