- Synthesis of sequentially deuterated 1-n-Butyl-3-methylimidazolium ionic liquids
-
Deuterium isotopologues of the ionic liquid (IL) 1-n-butyl-3- methylimidazolium chloride ([C4mim]Cl) sequentially labeled on the C-1″, C-1′, C-2′, C-3′, and C-4′ positions of the N-alkyl groups were prepared following a strategy that minimizes
- Khrizman, Alexander,Cheng, Hiu Yan,Moyna, Guillermo
-
experimental part
p. 401 - 407
(2012/07/13)
-
- Site-selective deuterium labeling of the tetrabutylammonium cation
-
Four separate selectively deuterated samples of tetrabutylammonium iodide have been prepared in which each one of the four nonequivalent alkyl carbons is separately and fully deuterated. These samples were prepared for nuclear magnetic resonance (NMR) studies of the aggregation of ion pairs in low polarity solvents.
- Heinsen, Melissa J.,Pochapsky, Thomas C.
-
p. 473 - 480
(2007/10/03)
-
- Intermediacy of ion neutral complexes in the fragmentation of short-chain dialkyl sulfides
-
The main fragmentation processes after electron ionization of butyl methyl and butyl ethyl sulfides are rationalized by the intermediacy of the ion neutral complex [RSH · methylcyclopropane](+·) as demonstrated by extensive labeling and collision activation studies.
- Filsak,Budzikiewicz
-
p. 601 - 610
(2007/10/03)
-
- A study of the gas-phase reactivity of neutral alkoxy radicals by mass spectrometry: α-Cleavages and Barton-type hydrogen migrations
-
The reactivity of neutral alkoxy radicals in the absence of any interfering intermolecular interactions is investigated by means of the recently introduced method of neutral and ion decomposition difference (NIDD) spectra. These are obtained from quantitative analysis of the corresponding neutralization - reionization (NR) and charge reversal (CR) mass spectra. The following trends emerge: alkoxy radicals with short (C1-C3) or branched alkyl chains give rise to α-cleavage products, whereas longer-chained alkoxy radicals undergo 1,5-hydrogen migrations from carbon to oxygen, that is, Barton-type chemistry. This facile rearrangement has been studied in detail for n-pentoxy radicals by isotopic labeling experiments and computation at the Becke 3LYP/6-31G* level of theory. Further, the NIDD spectra of 3-methylpentoxy radicals permit for the first time the identification of the diastereoselectivity of the gas-phase hydrogen migrations. The results from the NIDD method are compared to those from earlier studies in the condensed phase. This new mass spectrometric approach is suggested as a tool for the examination of intramolecular reactions of free alkoxy radicals which can usefully complement theoretical studies.
- Hornung, Georg,Schalley, Christoph A.,Dieterle, Martin,Schroeder, Detlef,Schwarz, Helmut
-
p. 1866 - 1883
(2007/10/03)
-