Dear all,

I ran an ESI-MS analysis on my sample of RuCl2(PPh3)3, but I can't seem to pinpoint the fragment that is responsible for the peaks observed around 633 m/z (see the spectrum attached).

Some details of the synthesis and characterisation:

- sample synthesised using RuCl3.xH2O + PPh3, refluxed at 100oC for 1 hr;

- for +ve ESI-MS: purified sample dissolved in DCM for stock, diluted 100 times using ACN, and 100% ACN used as the carrier, sodium present).

I identified the molecular ion peak at 743 m/z to be due to [RuCl(ACN)2(PPh3)2]+.

The peaks do not quite follow the isotopic distribution of ruthenium; I suspect that the fragment is ruthenium-free and could be due to side reactions of PPh3 and/or O=PPh3.