Mass spectra of organogermanes

Abstract

Ph6Ge,0, and Me,GeCI has been studied a t 70 ev under high resolution, and that of the organogermanes ( o mtolyl),Ge, Ph,GeX (X = Me, PhCH,. CI, Br. and I), R6Ge, (R = Et, Ph, m-tolyl), (PhCH,),GeH, Me,GeH ,and GeCI, a t low resolution. Almost all the ion-current is carried by rnetal-containing ions and in general the most favoured fragmentation processes are those leading to even-electron ions.MASS spectroscopic studies have been reported for a variety of organo-silanes,l -stannanes,, and -plumbanes and the purpose of this paper is to present a similar study of a representative selection of organogermanes, and to draw attention to significant differences. Organogermanes the mass spectra of which have already been reported include Me,Ge,, Pri4Ge, Pri,GePrn, ( Pri2GeO),, Pri6Ge2,, (CHiC),Ge,5 and Et,GeR (R = CiCCHXH,, CiCCHXHCH,, CiCC(Me):CH,) and in addition some organogermanes have been identified from their molecularIn a preliminary communication lo we summarised the main features of interest observed in the mass spectra of organo-germanes and -stannanes.

Fragmentation and rearrangement processes in the mass spectra of perhalogenoaromatic compounds. Part II. Pentafluorophenyl derivatives of GroupIV

“…highest for the silane, under the conditions of (b) (C6F4),Ge these experiments the yields of (C6F,),+' and The spectrum of the germane bears some re-(C6F,),+' are less than for the germane, con-semblance to that of (C,H,),Ge (1,10). The trary to earlier predictions (1).…”

“…The fluoroaromatic derivatives did not show ions corresponding to successive acetylene eliminations found for tetraphenyl derivatives of germanium, tin, and lead (10,11).…”

Gas‐Phase Chemistry and Mass Spectrometry ofGe‐,Sn‐ andPb‐Containing Compounds

“…The mass spectrum 30 of Me 3 GeH yields as a base peak the Me 2 GeH + ion (relative abundance 100) reflecting the fact that the Ge−H bond dissociation energy is larger than that of the corresponding Ge−C bond energy. However, important fragments are also observed (in decreasing order of abundance): MeGe + (35), Me 2 G +• (28) and Me 3 Ge + (22).…”

“…This behavior is very reminiscent of what is observed in the positive ion chemistry of tetramethoxygermane 81 . An additional interesting observation in this system is the fact that the pentacoordinated anion can undergo successive exchange reactions with fluorine-containing neutrals (BF 3 , SO 2 F 2 ) (equation 30). ion corresponds to a trigonal bipyramid with the F occupying an apical position.…”

Mass spectra of bis(trimethylsilyl)- and bis(trimethylgermyl)carbodiimide

“…The elimination of C2H6 from Me,GeNCNGeMe,+ is similar to that noted from Me,GeCl+ in the spectrum of Me3GeC1 (6) and the corresponding transition in the silicon analogue is metastable-confirmed. The elimination of C2H4 from Me3Ge+ is a well established pathway (6,7).…”