Keele Research Repository

Our aim was to identify the possible factors which controlled the photochemical reactions of benztropones or more widely , annulated tropones,by synthesising benztropones with electron-donating and electron-withdrawing substituents on the benzene ring.These substituents are far enough away to have no steric effects ;thus , steric effects which might be important if there are substituent groups on the seven membered ring are eliminated and only electronic effects which can be transmitted from the benzene ring are left .
The first chapter of this work reports a review of previous syntheses of annulated tropones,unsubstituted on the tropone ring .
The second chapter deals with the synthesis of the methoxybenztropones(38),(247)f(234) and (268), and 5H-benzo- cyclohepten-S-oned) and its substituted derivatives,such as
3-amino-,3-nitro-,3-acetamido-,3-amino-2,4-dibromo- and
6,8-dinitro-5H-benzocyclohepten-5-one (270),(20) ,(21),(272) , and (269) . The syntheses of 1-methyl-3-phenylcyclohepta(b)pyrrol-
-8-one(281).cyclohept(b)indol-10(5H)-one(8) and its methyl and ethyl derivatives (289),(285), as well as 4H-cyclohepta(b)furan-4-one(9) were also reported .
The third chapter is a review of photochemistry of tropones and annulated tropones .
Finally the fourth chapter reports the photochemistry of the benztropone and its substituted derivatives as well as tropones with fused hetero rings.