title: Investigation of the trans effect in the fragmentation of dinuclear platinum complexes by electrospray ionization surface-induced dissociation tandem mass spectrometry.
abstract: Cis and trans isomers of two dinuclear platinum complexes, [cis-¿Pt(NH3)2Cl¿2 mu-(NH2(CH2)nNH2)](NO3)2 (1,1/c,c) and [trans-¿Pt(NH3)2Cl¿2 mu-(NH2(CH2)nNH2)](NO3)2 (1,1/t,t), where the diamine was 1,4-butanediamine (n = 4) or 1,6-hexanediamine (n = 6), were studied using electrospray ionization surface-induced dissociation (ESI/SID) tandem mass spectrometry (MS/MS). The same fragment ions were observed for both the cis and trans isomers of each complex (n = 4 or 6), but the relative intensities were dependent on the isomer studied. The ESI/SID data and energy-resolved mass spectra show that the position of the chloride plays a significant role in the fragmentation of these ions. Two major fragmentation pathways were detected for the complexes. The cleavage of the Pt-N bond trans to chloride was the most favorable pathway for both isomers of the complexes following the ion-surface collision. The differences in the ESI/SID spectra between the cis and trans isomers can be explained by the trans effect, namely that the Pt-N bond trans to chloride is the most labile bond.
authors.affiliation: Department of Chemistry, Virginia Commonwealth University, Richmond 23284, USA.
authors.forename: T G
authors.initials: TG
authors.lastname: Schaaff
authors.forename: Y
authors.initials: Y
authors.lastname: Qu
authors.forename: N
authors.initials: N
authors.lastname: Farrell
authors.forename: V H
authors.initials: VH
authors.lastname: Wysocki
mesh_terms: D003959:Diamines; D008401:Gas Chromatography-Mass Spectrometry; D007536:Isomerism; D017671:Platinum Compounds / Q000737:chemistry*; D011700:Putrescine; D016339:Spectrometry, Mass, Fast Atom Bombardment; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D003959:Diamines; D017671:Platinum Compounds; D011700:Putrescine; C007297:1,6-diaminohexane