An examination of the coordination chemistry of L2Pt(1,2-dithiolenes) using atmospheric pressure chemical ionization mass spectrometry

Atmospheric pressure chemical ionization mass spectrometry (APCI-MS) has be en utilized in the characterization of two series of platinum dithiolene co mplexes, (COD)Pt(dt) 1, (COD)Pt(edt) 2, (COD)Pt(dmid) 3, (COD)Pt(mnt) 4, (C OD)Pt(eddo) 5, (COD)Pt(dddt) 6 and (Ph3P)(2)Pt(dt) 7, (Ph3P)(2)Pt(edt) 8, ( Ph3P)(2)Pt(dmid) 9, (Ph3P)(2)Pt(dmit) 10, (Ph3P)(2)Pt(mnt) 11 (where COD=1, 5-cyclooctadiene, dt=ethane-1:2-dithiolate. edt = ethylene-1,2-dithiolate, dmid = 1,3-dithiole-2-oxo-4,5-dithiolate, dmit = 1,3-dithiole-2-thione-4,5- dithiolate, mnt = maleonitrile-1,2-dithiolate, eddo = 4-(ethylene-1',2'-dit hiolate)-1,3-dithiole-2-one, and dddt = 5,6-dihydro-1,4-dithiin-2,3-dithiol ate). The series that contains triphenylphosphine is labile toward the loss of HPPh3+. In addition, an orthometallated species involving the platinum and triphenylphosphine is identified. A dimer is identified for 2, which is shown to be a product of the experiment and not present in the parent mate rial. In addition, a 1:1 adduct with NH4+ is identified for 4 and 11 where the NH4+ originates from the acid hydrolysis of acetonitrile. Finally, a hi ghly unique ion, Pt+, a bare platinum ion, is observed in all COD complexes indicating that a radical mechanism must accompany the decomposition of th e COD complexes during the fragmentation process.