13025-73-5Relevant academic research and scientific papers
Isomeric +. Ions: Their Identification and Generation in Dissociative Ionizations
Mommers, A. A.,Burgers, P. C.,Holmes, J. L.,Terlouw, J. K.
, p. 7 - 9 (1984)
The collisional activation (CA) and charge stripping (CS) mass spectra of the three +. isomers, allene, propyne and cyclopropene, are reported.The extent of isomerization among these ions prior to collisional excitation depends on their internal energy content, but is small.Each +. ion structure also can uniquely be generated via appropriate dissociative ionizations.Analysis of mixtures of +. (daughter) ion structures is, in general, not possible from CA and CS mass spectra alone but may be aided by appearance energy measurements.
Synthesis of [3-D3]-, [3-13C]-, and [1,2-13C2]propynes and their use for the synthesis of [5-D3-methyl]-, [5-13C-methyl]-, and [5,6- 13,C2-2,5-cyclohexadienyl]ubiquinones 3
Boullais, Claude,Rannou, Christelle,Reveillere, Emmanuel,Mioskowski, Charles
, p. 723 - 727 (2007/10/03)
Three selectively labeled propynes were prepared either with deuterium or carbon-13 at position 3 and doubly labeled with carbon-13 at positions 1 and 2 by an alkylation reaction from the corresponding labeled or unlabeled monolithio acetylides and dimethylsulfates. Their lithiation with nBuLi gave the corresponding propynyllithium derivatives which reacted with dimethyl squarate to afford the corresponding propargylic alcohols. These were thermolysed in p-xylene to furnish [5-D3-methyl]-, [5-13C-methyl]-, and [5,6-13C2-2,5-cyclohexadienyl]ubiquinone. The farnesyl side chain was introduced onto the labeled quinones with farnesyl trimethyltin under BF3 catalysis to provide [5-D3-methyl]-, [5-13C-methyl]-, and [5,6-13C2- 2,5-cyclohexadienyl]ubiquinone 3 (6c, 6b, 6a, respectively).
