DETERMINATION OF DOUBLE BOND POSITION AND GEOMETRY OF OLEFINS BY MASS SPECTROMETRY OF THEIR DIELS-ALDER ADDUCTS.

Article abstract of DOI:10.1021/ac00251a013

The Diels-Alder reaction of olefins with ketals of tetrachlorocyclopentadiene produces adducts, the mass spectra of which clearly identify the position and geometry of the original double bond. The loss of either substituent determines the position of the olefin, and the relative abundances of the resultant ions can be related to the geometry. These ions are at least 5-fold more abundant on the product derived from the Z-olefin. The spectra are simpler than the spectra of other derivatives previously used for this purpose and the sensitivity of the technique is such that it can be applied at the microgram level. The ions indicative of the molecular weight of the adduct are very prominent even though the molecular ion is absent.