Formation and rearrangement of tricyclo[7.1.1.04,10undeca-2,4,6,8-tetraen-10-ol, novel pathway from bicyclo[4.4.1]undeca-1(10),2,4,8-tetraen-11-one to 4-methylazulene
By the action of LDA bicyclo[4.4.]udeca-1(10),2,4,8-tetraen-11-one was found to undergo transannularcyclization to form a unique tricyclic hydroxydihydroazulene which cleaves a CC bond by [π8s+σ2s] electrocyclic process and eventually give 4-methylazulene.