With the use of four- to eight-fold functionalized dodecahedranes (1-3), opportunities to arrive at highly strained dodecahedranes with two to four pairs of vicinal, eclipsed bromine substituents through front-side substitution and addition reactions have been explored. In standard processes, the interception of beta-OCH(3) radical/cationic intermediates was not problematic (9-12, 37, 50). The interception
The pagodane route to dodecahedranes-functional group manipulations on the dodecahedrane sphere
作者:Klaus Scheumann、Fabian Wahl、Horst Prinzbach
DOI:10.1016/s0040-4039(00)92325-6
日期:1992.1
Reductive and halogenative Barton decar☐ylation methodologies provide an expeditious access to variously 1,6-di- and 1,6,11,16-tetrasubstituted pentagonal dodecahedranes. Vicinal CO2R and Cl substituents cause increasing competition in the radical transfer step.
For two- to six-fold functionalised dodecahedranes (7–10) the chances for selective variation of their substitution have been explored, as part of a program directed at homododecahedranes and at highly unsaturateddodecahedranes, ultimately C20fullerene. With 1,6-dimethyl ester 7 several side chain transformations next to the very bulky dodecahedral cage were effected (1,6-bismethylene derivatives