105930-63-0Relevant academic research and scientific papers
Sequential Hydrogen Tunneling in o-Tolylmethylene
Lohmiller, Thomas,Sarkar, Sujan K.,Tatchen, J?rg,Henkel, Stefan,Schleif, Tim,Savitsky, Anton,Sanchez-Garcia, Elsa,Sander, Wolfram
, p. 17873 - 17879 (2021)
o-Tolylmethylene 1 is a metastable triplet carbene that rearranges to o-xylylene 2 even at temperatures as low as 2.7 K via [1,4] H atom tunneling. Electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) spectroscopical techniq
Direct Spectroscopic Observation of Intramolecular Hydrogen Shifts in Carbenes
McMahon, Robert J.,Chapman, Orville L.
, p. 683 - 692 (2007/10/02)
Triplet o-tolylmethylene (13a) decays thermally to singlet o-xylylene (14a) in an argon matrix at temperatures as low as 4.6 K.The thermal, intramolecular -hydrogen shift has been observed directly by IR and UV spectroscopy.The carbene disappearance kinetics follow the standard (time)1/2 dependence, due to multiple reaction sites in the matrix.The small temperature dependence and non-Arrhenius behavior of the rate implicate a tunneling mechanism.In contrast, triplet 1-phenylethylidene (17a) is thermally stable in argon or xenon matrices at 10 K.Warming 17a to 65 K in a xenon matrix produces styrene (18a).The intramolecular -hydrogen shift has been observed directly by IR spectroscopy.The carbene disappearance kinetics show apparent first-order behavior.We estimate an upper limit of ca. 4.7 kcal/mol for the singlet-triplet energy gap in 17a.
