ABSTRACT
We have the accurate mass from the high resolution mass spectrum in this case. There are calculators that provide the most probable molecular formulas from the monoisotopic mass (www.chemcalc.org, Patiny and Borel 2013). From given accurate molecular mass, the formula whose mass is closest to the experimental value is C4H8O. Therefore, the compound is a little oxygen molecule with a hydrogen deficiency index of 1. In the LRMS, the fragment formed by loss of 17 mass units (m/z = 55, 10%) and the ion whose m/z value is 45 (30%) suggest that the molecule is an aliphatic alcohol. The relative abundance of the molecular ion in the LRMS is quite low, which is something usual in alcohols since loss of hydroxyl group or dehydration take place quite easily. In addition, M-15 (M-CH3) is the base peak (m/z 57), thus suggesting that both hydroxy and methyl groups are bound to the same carbon (α-cleavage).
