TY - JOUR
T1 - Intracluster cyclization reaction producing a benzene derivative
T2 - Photoionization mass spectrometric study of alkali metal-methyl propiolate clusters
AU - Tsunoyama, Hironori
AU - Ohshimo, Keijiro
AU - Misaizu, Fuminori
AU - Ohno, Koichi
N1 - Funding Information:
The authors thank to the Computer Center of the Institute for Molecular Science for provision of the Fujitsu VPP5000 computer. This work has been supported in part by a Grant-in-Aid for Scientific Research from the Japanese Ministry of Education, Science, Sports and Culture. Financial support from Mitsubishi Foundation is also acknowledged. H.T. and K. Ohshimo are supported by the Research Fellowship of the Japan Society for the Promotion of Science for Young Scientists. Dr. Hajgato Balazs is also acknowledged for critical reading of the manuscript.
PY - 2004/3/1
Y1 - 2004/3/1
N2 - Size-dependent stability and intracluster reactions have been investigated by photoionization mass spectrometry for alkali metal (M; Li, Na, and K)-methyl propiolate (MP; HC≡CCOOCH3) molecules clusters. In the photoionization mass spectra, the intensities of M+(MP)3 ions (M=Na and K) were unexpectedly high, whereas no intensity anomaly was observed in Li+(MP)n mass spectrum. The intensity anomaly can be explained by intracluster cyclization reaction induced by electron transfer from the metal atom and resulting a stable benzene derivative formation. Ion intensities of M+(MP)n(H2O) relative to M+(MP)n have a minimum at n=3 in Na and K systems. This result is owing to evaporation of water and/or MP molecules following exothermic cyclization reaction. Fragment ions with a loss of CH 2 were also observed predominantly from M(MP)2 in all metal systems. These ions are expected to be produced by hydrolysis in M(MP)n(H2O) clusters producing a HC≡CCOOH molecule. The difference between lithium and other alkali metals is due to the rigidity of clusters with respect to deformation into geometry leading to the polymerization reaction.
AB - Size-dependent stability and intracluster reactions have been investigated by photoionization mass spectrometry for alkali metal (M; Li, Na, and K)-methyl propiolate (MP; HC≡CCOOCH3) molecules clusters. In the photoionization mass spectra, the intensities of M+(MP)3 ions (M=Na and K) were unexpectedly high, whereas no intensity anomaly was observed in Li+(MP)n mass spectrum. The intensity anomaly can be explained by intracluster cyclization reaction induced by electron transfer from the metal atom and resulting a stable benzene derivative formation. Ion intensities of M+(MP)n(H2O) relative to M+(MP)n have a minimum at n=3 in Na and K systems. This result is owing to evaporation of water and/or MP molecules following exothermic cyclization reaction. Fragment ions with a loss of CH 2 were also observed predominantly from M(MP)2 in all metal systems. These ions are expected to be produced by hydrolysis in M(MP)n(H2O) clusters producing a HC≡CCOOH molecule. The difference between lithium and other alkali metals is due to the rigidity of clusters with respect to deformation into geometry leading to the polymerization reaction.
KW - Alkali metal
KW - Cyclization
KW - Intracluster reaction
KW - Photoionization
KW - Polymerization
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U2 - 10.1016/j.ijms.2003.11.003
DO - 10.1016/j.ijms.2003.11.003
M3 - Article
AN - SCOPUS:1542381020
SN - 1387-3806
VL - 232
SP - 41
EP - 50
JO - International Journal of Mass Spectrometry
JF - International Journal of Mass Spectrometry
IS - 1
ER -