Aromatization-driven Grob-fragmentation approach toward polyazaacenes. Synthesis and amination of multi-functionalized diazapentacenes
作者:Teh-Chang Chou、Ju-Fang Cheng、Atul R. Gholap、Jim Jing-Kai Huang、Jyun-Chang Chen、Jing-Kai Huang、Jui-Chang Tseng
DOI:10.1016/j.tet.2019.130689
日期:2019.11
A general approachtoward the synthesis of multi-functionalized diazapentacene derivatives 1, using 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene (TDCp, 2), a substituted benzene-1,2-diamine (ADA, 6), and a naphthalene-1,4-dione (BQ, 3) as the building units, is described. The synthesis basically entails three operations: (i) oxidation of the dichloroetheno-bridge in the Diels-Alder cycloadduct
The development of an expedient synthesis toward quinoxaline ring-embedded polyacenoquinone esters with the generic structure A is demonstrated by the synthesis of penta- and hexacenoquinone esters. They are potential n-type small molecules, capable of undergoing successive reductions and self-assembling in face-to-face pi-stacks.
A facially dissymmetric 1,3-cyclohexadiene as a dienophile in diels-alder reactions with polyhalocyclopentadienes
作者:Alan P. Marchand、Umesh R. Zope、Andrew Burritt、Simon G. Bott、James M. Coxon
DOI:10.1016/0040-4020(95)00519-e
日期:1995.8
Diels-Alder cycloaddition of 1,2,3,4,5,5-hexachloro- and of 5,5-dimethoxy-1,2,3,4-tetrachlorocyclopentadiene (2a and 2b, respectively) to hexacyclo[10.2.1.0(2,11).0(4,9).0(4,14).0(9,13)]pentadeca-5,7-diene-3,10-dione (1) occurs in each case with highly stereoselective attack of the diene upon that face of the dienophile which is anti to the carbonyl groups. The corresponding endo,anti adduct (i.e., 6 and 8, respectively) is obtained as the exclusive cycloadduct in each case. The structures of 6 and 8 were established unequivocally via X-ray crystallographic methods. The results of AM1 semi-empirical MO calculations for cycloaddition of 1 to 2a are in accord with experiment.