trans-Cycloalkenes. Part V. 1-Methyl-trans-cyclo-octene

Abstract

The reactions of 1-methyl-trans-cyclo-octene (I) with a number of reagents have been investigated for comparison with the reactions of bicyclo[3.3.1]non-1-ene (II) and trans-cyclo-octene. Towards cycloadditions and addition of alkyl-lithium, 1-methyl-trans-cyclo-octene (I) is no more reactive than trans-cyclo-octene, indicating similar strain energies, but appreciably less reactive than the bicyclononene (II), which is considerably more strained. In electrophilic additions however, the methyl derivative (I) reacts more rapidly than trans-cyclo-octene owing to the presence of the electron-releasing methyl group. Treatment of compound (I) with 4-phenyl-1,2,4-triazoline-3,5-dione gave rapidly the product (X) of an ‘ene’ reaction.