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The mass spectra of a number O-alkylthionocarbamates with two, one or no alkyl substituents on the nitrogen atom are presented and discussed. The main primary fragmentation pathways are McLafferty rearrangements, including the double so-called protonated McLafferty rearrangement. Generally, rearrangement products give charge delocalized ions, which release hydroxyl or sulphydryl radicals and water or hydrogen sulphide, to produce stable fragments. It has been found that the position of alkyl moieties may be deduced on the basis of mass spectral fragmentation patterns. [ABSTRACT FROM AUTHOR]

The quantitative isomerization of (Z)- to (LD-alkene in protic, imidazolium ionic liquids is demonstrated. The isomerization parameters were determined. The mechanism on the addition of the protic imidazolium species to carbon-carbon double bond is presented. [ABSTRACT FROM AUTHOR]

The electron impact mass spectra of 5,8-diethyl-7-hydroxydodecan-6-one ( Z)-oxime and ( E)-oxime provide a basis for distinguishing these stereoisomers. [ABSTRACT FROM AUTHOR]

Abstract: Protic imidazolium ionic liquids have been tested as reaction media in the Diels–Alder reaction between cyclopentadiene and two dienophiles (dimethyl maleate and methyl acrylate). Good conversions and endo/exo selectivities were achieved. The activation of the dienophile by hydrogen bonding with protic imidazolium ILs was demonstrated. [Copyright &y& Elsevier]