Cycloreversion and other gas-phase reactions of neutral and cationic pyrrolidine-fused chlorins and isobacteriochlorins under ion bombardment and electrospray

Neutral and cationic pyrrolidine‐fused chlorins and isobacteriochlorins derived from meso‐tetrakis(pentafluorophenyl)porphyrin undergo cycloreversion reactions in the gas phase, either when desorbed from a liquid matrix by ion bombardment or when electrosprayed. Cycloreversion occurs through loss of either neutral or charged moieties, with and without hydrogen and methyl radical migration, and both as high‐ and low‐energy collision processes. For the doubly charged isobacteriochlorin, one‐electron reduction with methyl loss occurs under ion bombardment and electrospray, through hypervalent pyrrolidinium radical formation. Copyright © 2004 John Wiley & Sons, Ltd.