APPLICATION OF ELECTROSPRAY MASS-SPECTROMETRY TO THE CHARACTERIZATIONOF HYDROXYMETHYLPHOSPHONIUM SALTS, HYDROXYMETHYLPHOSPHINES, AND THEIROXIDE, SULFIDE AND SELENIDE DERIVATIVES
W. Henderson et Gm. Olsen, APPLICATION OF ELECTROSPRAY MASS-SPECTROMETRY TO THE CHARACTERIZATIONOF HYDROXYMETHYLPHOSPHONIUM SALTS, HYDROXYMETHYLPHOSPHINES, AND THEIROXIDE, SULFIDE AND SELENIDE DERIVATIVES, Polyhedron, 15(13), 1996, pp. 2105-2115
Air-stable hydroxymethylphosphonium salts, readily synthesized from th
e appropriate primary, secondary or tertiary phosphine, formaldehyde a
nd HCl, provide an excellent means of characterizing phosphines by ele
ctrospray mass spectrometry. Results are discussed in terms of fragmen
tation and aggregation of the parent molecular ion species, where loss
of a CH2OH group is a common fragmentation route. For monophosphonium
salts, parent ions M(+) were typically observed as the base peaks in
positive-ion spectra, with the tendency to aggregate to form species o
f the type [M(2)Cl](+), [M(3)Cl(2)](+) and [M(4)Cl(3)](+) (M = phospho
nium ion) increasing with the number of CH2OH groups. Related aggregat
es, e.g. [M(2)Cl(3)](-), were observed in the negative-ion spectra. In
situ formation of silver(I) adducts of a number of phosphines and the
ir sulphide derivatives provides an additional means of characterizati
on, though this method was not applicable to phosphine selenides. For
phosphine oxides, adducts are readily detected with alkali metal ions.