4-Ferrocenyl-1,3-Pentadiene

Abstract

The polymerization characteristics of numerous vinyl-type ferrocene monomers have been studied in recent years,¹but similar information on conjugated diene monomers has been less extensive. As part of our systematic investigations now underway in this general area, we had need for an appreciable quantity of 4-ferrocany1-1,3-pentadiene. Of the several methods previously described²for the generation of olefinic side chains on ferrocene nuclei, none turned out to be entirely satisfactory for intermediate or large scale synthesis, due in large part to the propensity of these olefinic side chains, once generated, to undergo rapid polymerization reactions under the experimental conditions usually chosen. We now report a convenient synthetic route to 4-ferroceny1-1,3-pentadiene which makes use of the well known wittig reaction as shown in the following equation