New aldehydes by catalytic diene cycloisomerisations

Abstract

The Rh-catalysed hydroformylation of isopropylidenecyclohexane derivatives obtained by intramolecular diene cyclisations affords the corresponding aldehydes in good yields and in a completely chemo- and regioselective manner. Diastereoselectivities of ca. 90%were achieved for all substrates when a bulky phosphite was used as the Rh ligand. The stereochemical outcomes of the hydroformylation reactions were established by detailed NMR studies. The olfactory evaluation of the different aldehydes is also presented.