Enynes, easily obtained by the Sonogashira coupling reactions of aromatic iodides. undergo. with good yields, en ne metathesis using the Grubbs catalyst. The resulting dienes are interesting carbo- and heterocycles which can give complex natural frameworks by Diels Alder reactions. Thus. an estradiol type skeleton is obtained in two steps from the corresponding enynes. An example of a metathesis-Diels-Alder cascade one-pot process is reported. (C) 2001 Elsevier Science Ltd. All rights reserved.