At an early stage of our examination2 of the dehydrogenation products of the diterpene cafestol, it was desirable to have available for comparison purposes all of the possible ethylphenanthrenes and the synthesis of the missing isomer-4-ethylphenanthrene-was consequently undertaken. The most obvious approach involved reaction of 4-keto-l12, 3, 4- tetrahydrophenanthrene (I) with ethylmagnesium iodide followed by dehydration and ...
