Mass spectral fragmentation patterns of heterocycles Part 1. 1,4-Benzodioxans

The mass spectral fragmentation pattern of a series of substituted 1,4-benzodioxans is reported. The 2,3-disubstituted compounds show a characteristic fragment peak at mass 121. The 2-monosubstituted compounds do not show this as fragment peak. The mass peak at 121 has been assigned the empirical formula of C₇ H₅ O₂.