THREE STUDIES OF 2-PYRIDONE PHOTOADDUCT REACTIVITY

Abstract

2-Pyridones such as iii undergo efficient [4+4] photocycloaddition reactions, yielding strained tricyclic cyclooctadiene structures iv and v, with functionality at every carbon. As part of a program to develop the chemistry of these complex adducts, three studies have been conducted. Halogenation of trans iv give rearranged i. Cope rearrangement of cis v gives vi which can undergo retro-Mannich reaction to yield unsymmtrically coupled piperidines vii. Pyridones can also undergo photo-[4+4] reactions with furans. Cycloaddition of viii yields ix. Transannular closure of ix produces triquinane x, a model system for total synthesis of crinipellin A xi.