Superoxide chemistry revisited: synthesis of tetrachloro-substituted methylenenortricyclenes

• Basavaraj M. Budanur and
• Faiz Ahmed Khan

Beilstein J. Org. Chem. 2014, 10, 2531–2538, doi:10.3762/bjoc.10.264

• . Keywords: BHT; dehydrohalogenation/rearrangement; Friedel–Crafts acylation; methylenenortricyclene; superoxide ion; Introduction The chemistry of the superoxide ion (O2−·) has been a subject of growing interest because of its presence in all aerobic organisms as a respiratory intermediate [1][2][3][4][5

• olefinic peaks in the 13C NMR are not in accordance with our expectations. The single crystal X-ray analysis of the product (Figure 1) sorted out all the ambiguity associated with structure. To our pleasant surprise the structure of the product was methylenenortricyclene 5a which seems to have been formed

• , substituted styrene adducts were subjected to the reaction with KO2 (3 equiv) in DMSO and the results are summarized in Scheme 2. The substrates endowed with electron donating groups, for example anti-adduct 3b gave methylenenortricyclene 5b, whereas its syn-isomer 4b, after consumption of all the starting