Facile One-Pot Synthesis and Crystal Structure of 2:1 Adducts of Myrcene (or Ocimene) with Benzoquinones

One-pot tandem oxidation and double Diels-Alder reaction of myrcene or ocimene with in situ generated 1,4-benzoquinone or 1,2-benzoquinone at 0°C for 1.5 h yielded polyalkylated 1,4,4a,5,8,8a,9a,10a-octahydro-9,10-anthracenediones and bis(alkylated) 9,10-phenanthrenedione respectively. The structure of novel bis-adduct from ocimene, (1R,4aR,5S,8aS,9aS,10aR)-rel- 1,4,4a,5,8,8a,9a,10a-octahydro-2,6-dimethyl-1,5-bis(3-methyl-2-buten-1-yl)-9,10-anthracenedione, was elucidated through single crystal X-ray analysis.