Comment on "The chemical reactions in electrosprays of water do not always correspond to those at the pristine air-water interface" by A. Gallo Jr, A. S. F. Farinha, M. Dinis, A.-H. Emwas, A. Santana, R. J. Nielsen, W. A. Goddard III and H. Mishra, Chem. Sci. , 2019, 10 , 2566

Recently, Gallo ( 2019, 10, 2566) investigated whether the previously reported oligomerization of isoprene vapor on the surface of pH < 4 water in an electrospray ionization (ESI) mass spectrometer ( 2012, 116, 6027 and 2018, 20, 15400) would also proceed in liquid isoprene-acidic water emulsions. Gallo hypothesized that emulsified liquid isoprene would oligomerize on the surface of acidic water because, after all, isoprene, liquid or vapor, is always a hydrophobe. In their emulsion experiments, isoprene oligomers were to be detected by proton magnetic resonance ( H-NMR) spectrometry.