THE SYNTHESIS AND REACTIONS OF TRICYCLO(4.2.0.0(1,4))OCTANE; ALIAS SEMI-WINDOWPANE.

摘要

The synthesis of tricyclo{4.2.0.0('1,4)}octane was accomplished. The reaction sequence contained sixteen steps. The most important reactions included a Dieckmann condensation which formed the third ring and two separate ring contractions involving the Wolf rearrangement of diazoketones. An X-ray crystal structure determination was carried out on the p-bromoanilide of tricyclo{4.2.0.0('1,4)}octane-3-carboxylate. The geometry about the central carbon is best described as distorted tetrahedral.;The reactions of the hydrocarbon and some of its derivatives were examined. The parent hydrocarbon was thermolyzed and an activation energy of 36.3 kcal/mol was measured, which may be compared with E(,a) = 36.0 kcal/mol for bicyclo{2.2.0}hexane. The solvolysis of tricyclo{4.2.0.0('1,4)}oct-3-yl 3,5-dinitrobenzoate indicated that the endo isomer reacted much faster than the exo isomer. The rate constant for the endo isomer at 70(DEGREES)C in 80% acetone/water was, k = 4.7 x 10('-5) sec('-1). The catalyst, di-(mu)-chloro-bis(bicyclo{2.2.1}hepta-2,5-diene) dirhodium (I), failed to react with the parent hydrocarbon.