Some fulvalenoids containing 1,3-dithiepin counterpart (5a), (5b), and (5c) have been synthesized through the reaction of 2-trimethylsilyl-1,3-dithiepinide ion (6) with di-tert-butyl-cyclopropenone, 2,3;6,7-dibenzotropone, and fluorenone, respectively. Comparison of the 1H-NMR spectra of these fulvalenes indicated the electron accepting ability of the 1,3-dithiepin moiety.
Two series of [8]metacyclophanes with cis or trans configurated double bonds or triple bonds in the bridges were prepared; the first series 6, 8, and 10 contains phenylethynyl, the second series 13, 14, and 15 phenylethenyl substituents so that ππ interactions between the π centres in the bridge and the π centres of the basic chromophores tolan and trans-stilbene, respectively, can be studied.
The cyclophanes 6,8,10 and 13–15 were synthesized by cesium assisted ring closure reactions. The main interest in these systems concerns the interaction of the unsaturated bridge with the tolan and the stilbene chromophores, respectively.
Conformational study of the 4,9-dihetero-(Z,Z)-cyclodeca-1,6-diene ring system; the mono- and di-benzo analogues
作者:E. Kleinpeter、J. Hartmann、W. Schroth
DOI:10.1002/mrc.1260280713
日期:1990.7
The dynamic 1H and 13C NMR spectra of a series of mono‐ and bis‐annelated 4,9‐dihetero‐(Z,Z)‐cyclodeca‐1,6‐dienes were obtained and are discussed with respect to ground‐state conformers and the barriers to ring inversion, and to the restricted rotation about exocyclic partial C,N double bonds. The ten‐membered rings are, with one exception, anancomeric chair conformers and interconvert via a combination