MASS SPECTROMETRY OF ARALKYL COMPOUNDS WITH A FUNCTIONAL GROUP .7. ON STRUCTURE OF IONS C8H9+ FROM C6H5C2H4X- AND C9H11+ FROM C6H5C3H6X-COMPOUNDS

The C8H9+‐ion, formed from the molecular ions of 2‐phenyl‐1‐bromoethane, 1‐phenyl‐1‐bromoethane and of 1‐phenyl‐1‐nitroethane by loss of the bromine atom and of the nitro group, splits off a molecule of acetylene after an almost complete randomization of hydrogens, as proved by deuteration. An eight‐membered ring structure for the C8H9+‐ion is proposed to explain these results. By loss of the nitro group from the molecular ions of 1‐phenyl‐1‐nitropropane and of 1‐phenyl‐2‐nitropropane the well‐known phenylated cyclopropane ion3 (C9H11)+ is generated. Mass spectra of analogues, specifically deuterated in the side‐chain, show that in this ion a randomization of hydrogen atoms in the cyclopropane ring as well as a hydride transfer from the cyclopropane ring to the phenyl cation occur. Copyright © 1969 John Wiley & Sons, Ltd.