A novel method for the formation of 2-azocanones by lactone-to-lactam ring contraction of 2-oxonanones

Article abstract of DOI:10.1016/S0040-4039(98)02093-0

As part of a project evaluating medium-ring lactams as constrained peptidomimetics, a novel method for the formation of multisubstituted eight- membered lactams has been developed. N-Protected 7-amino-8-hydroxy-octenoic acids were cyclised to give 8-amino-5,6-dehydro-2-oxocanones which underwent clean intramolecular O-to-N-acyl (lactone-to-lactam) ring contraction to yield 8-hydroxymethyl-6,7-dehydro-2-azocanones, suitable for elaboration to eight-membered lactam dipeptides.