Étude de la flash thermolyse du méthyl-5 azido-2 thiadiazole-1,3,4 par spectroscopie photoélectronique (HeI) et calculs quantiques

1988 ◽  
Vol 66 (11) ◽  
pp. 2830-2834 ◽  
Author(s):  
I. B'Shary ◽  
C. Guimon ◽  
M. Grimaud ◽  
G. Pfister-Guillouzo
Keyword(s):  
Photoelectron Spectroscopy ◽  
Ring Opening ◽  
Vapour Phase ◽  
Mndo Method ◽  
Ultraviolet Photoelectron Spectroscopy

The flash thermolysis of 5-methyl 2-azido 1,3,4-thiadiazole (vapour phase: 10−2 mbar) was studied by ultraviolet photoelectron spectroscopy (HeI). The products detected (H2C=C=S, HCN, and N2) suggest that the unstable thiadiazole-nitrene undergoes a ring opening to form a linear thione 4, which generates the thiocetene H2C=C=S. This step was theoretically analysed by the MNDO method.

A study of the vacuum pyrolysis of 4-diazo-3-isochromanone with Hel ultraviolet photoelectron spectroscopy

1995 ◽  
Vol 73 (10) ◽  
pp. 1738-1740 ◽  
Author(s):  
N.H. Werstiuk ◽  
J. Ma ◽  
C.D. Roy ◽  
A.J. Kresge ◽  
E. Jefferson
Keyword(s):  
Mass Spectrometry ◽  
Heat Source ◽  
Photoelectron Spectroscopy ◽  
Laser Power ◽  
Ring Opening ◽  
Power Level ◽  
Ultraviolet Photoelectron Spectroscopy ◽  
Photoionization Mass Spectrometry ◽  
Cw Laser ◽  
Vacuum Pyrolysis

A newly developed ultraviolet photoelectron spectrometer – CO2 laser instrument that utilizes a 50-W CW laser as a directed heat source was used to study the vacuum pyrolysis of 4-diazo-3-isochromanone (1). Analysis of the pyrolysate with ultraviolet photoelectron spectroscopy and photoionization mass spectrometry established that 1 undergoes a facile, unexpected pyrolysis at a laser power level of 26 W yielding N2, CO, and benzocyclobutenone (6). A multistep mechanism beginning with the formation of 4-carbena-3-isochromanone (2), which rearranges to oxaketene 3, can be written for the reaction. If 3 is an intermediate, it must be unusually thermally labile for it readily decarbonylates to 2-carbena-3,4-benzotetrahydrofuran (4). The ring opening of 4 into the ortho-quininoid ketene 5 and the cyclization of 5 into 6 are possible final steps in the conversion of 1 into 6. Keywords: vacuum pyrolysis, 4-diazo-3-isochromanone, HeI ultraviolet photoelectron spectroscopy.

Surface potential of liquid microjet investigated using extreme ultraviolet photoelectron spectroscopy

2020 ◽  
Vol 152 (14) ◽  
pp. 144503
Author(s):  
Junichi Nishitani ◽  
Shutaro Karashima ◽  
Christopher W. West ◽  
Toshinori Suzuki
Keyword(s):  
Surface Potential ◽  
Photoelectron Spectroscopy ◽  
Extreme Ultraviolet ◽  
Ultraviolet Photoelectron Spectroscopy

Vacuum ultraviolet photoelectron spectroscopy of transient species

1981 ◽  
Vol 44 (5) ◽  
pp. 1059-1066 ◽  
Author(s):  
J.M. Dyke ◽  
N.B.H. Jonathan ◽  
A. Morris ◽  
M.J. Winter
Keyword(s):  
Photoelectron Spectroscopy ◽  
Vacuum Ultraviolet ◽  
Ultraviolet Photoelectron Spectroscopy ◽  
Transient Species

Ultraviolet Photoelectron Spectroscopy of Polymers

2006 ◽  
Vol 455 (1) ◽  
pp. 193-203 ◽  
Author(s):  
M. P. de Jong ◽  
R. Friedlein ◽  
W. Osikowicz ◽  
W. R. Salaneck ◽  
M. Fahlman
Keyword(s):  
Photoelectron Spectroscopy ◽  
Ultraviolet Photoelectron Spectroscopy
Sign in / Sign up

Export Citation Format

Share Document