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Synthesis of mixed‐substituted tetraphosphetanes (RP−PtBu)2 (R=Ph (4), Py (5); Py=2‐pyridyl) is achieved from the condensation of dipyrazolylphosphanes RPpyr2 (R=Py (1), Ph (3); pyr=3,5‐dimethylpyrazolyl) as P1‐building block (R−P) and tBuPH2 in an equimolar ratio. Compound 5 is of special interest since the presence of two pyridyl‐substituents as well as the P4‐core allows for a rich coordination chemistry with coinage metal salts [Cu(MeCN)4][OTf], Ag[OTf] and in situ formed [Au(tht)][OTf] (tht=tetrahydrothiophene). Both tetraphosphetanes undergo alkylation reaction with MeOTf to give a series of tetraphosphetanium and tetraphosphetanediium triflate salts with additional methylation of the pyridyl‐moiety in case of 5 resulting in interesting novel cyclic trications. Harsh reaction condition and an excess of MeOTf converts 5 into the cyclic trication [‐P(MePy)PMe2P(MePy)PtBu‐]3+ (133+; MePy=1‐methylpyridiniumyl) through the elimination of isobutene. This salt undergoes a complicated rearrangement reaction involving a P−P/P−P bond metathesis to form trication [‐P(MePy)3PtBu‐]3+ (173+) when reacted with Me2PPMe2. [ABSTRACT FROM AUTHOR]