The title (CH) ,* hydrocarbon $ has the potential to undergo a series of.structurally degenerate Cope rearrangements* , one of which is illustrated below. The complete cycle leads to the scrambling pattern shown in E: eight positions (marked l ) form one equivalent set, while the remaining four comprise another. As shown, each Cope rearrangement also interchanges enantiomers. Thus, rapid rearrangement would be evidenced in a temperature dependent nmr spectrum; slower reaction might.be followed by the racemization of (partially) resolved 1. We now report the synthesis of racemic ,J,, and some preliminary thermal studies. 1 2 The synthesis begins with bicyclo[3.3.O]octa-3,7-diene-2,6-dione 2.3 Reduction of ,$ with diisobutylaluminum hydride4 in toluene at -40" gave a mixture of epimeric dienediols (89% yield); low temperature recrystallization from acetone afforded the major isomer, c& mdiol $5 (m.p. 93-93.7'). Orthoester Claisen rearrangement6 of $ required drastic conditions (e.g., several days in boiling triethylorthoacetate with continuous distillation and frequent addition of pivalic acid catalyst), reflecting the congestion beneath the bicyclic nucleus and presumably the enforced boat-like transition state. The oily diester z5 was obtained in 52% yield after distillation, removal of lactone Q5 (m.p. 84.8-85.2") by precipitation with hexane, and chromatography on acidic alumina to remove the mixed ester 1.5