g What two carbonyl compounds are needed to synthesize each of the following compounds, using a Robinson annulation? Part A A line-angle formula shows a ring with six vertices and a double bond between the second (clockwise) and the third vertices. An oxygen atom is double-bonded to the first vertex. A COCH3 group, whose first (from left to right) carbon is double-bonded to an oxygen atom, is attached to the fourth vertex.