Solution and Solid State Multinuclear NMR Investigation of the Structure of {(BuSn)12O14(OH)6}(O2PPh2)2

{(BuSn) 12 O 14 (OH) 6 }(O 2 PPh 2 ) 2 has been prepared from {(BuSn) 12 O 14 (OH) 6 }(OH) 2 and diphenylphosphinic acid. Its full characterization by solution 1D ( 1 H, 13 C, 119 Sn, and 31 P) and 2D gradient-assisted ( 1 H− 119 Sn HMQC, 1 H− 13 C HMQC, 1 H ROESY, and 31 P− 1 H HOESY) NMR is reported and shows that in CD 2 Cl 2 or CD 2 Cl 2 /DMSO- d 6 (1/1) the charge compensating diphenylphosphinate anions remain close to the “cage-poles” of the macrocations. A model for the geometry of the interaction is proposed. 119 Sn and 31 P MAS NMR characterization of the title compound is also reported.