Premium
Characterisation of a series of acetals/ketals of bis(2‐nitrophenyl) ethanediol and bis(4,5‐dimethoxy‐2‐nitrophenyl) ethanediol under APCI mass spectrometric conditions
Author(s) -
Bhaskar G.,
Prabhakar S.,
Ravi Kumar M.,
Narsimhaji Ch. V.,
Srinivas K.,
Vairamani M.
Publication year - 2006
Publication title -
journal of mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.475
H-Index - 121
eISSN - 1096-9888
pISSN - 1076-5174
DOI - 10.1002/jms.1062
Subject(s) - chemistry , mass spectrometry , organic chemistry , chromatography , medicinal chemistry
A series acetals/ketals of aldehydes and ketones formed by the reaction of two photolabile protecting groups, bis(2‐nitrophenyl) ethanediol and bis(4,5‐dimethoxy‐2‐nitrophenyl) ethanediol (I and II, respectively), were analysed under EI, LSIMS, ESI and APCI conditions to obtain molecular weights as well as structural information. The EI and LSIMS techniques failed to give molecular weight information. The positive ESI yielded [M + H] + ions only for I; however, with added Na + both I and II formed [M + Na] + adducts. But upon decomposition, the [M + Na] + ions yielded Na + ion as the only product ion. Similarly, under negative ion ESI conditions both I and II gave molecular weight information by forming adduct ions with halide anions (F − , Cl − , Br − and I − ); however, they did not give structural information as they resulted in only the halide anion as the abundant fragment ion upon dissociation. All the compounds formed abundant M −• ions under negative ion APCI conditions, and their MS/MS spectra showed characteristic fragment ions; hence the acetals/ketals of I and II could be successfully characterized under negative ion APCI conditions. Copyright © 2006 John Wiley & Sons, Ltd.