The synthesis of halogenated phthalonitriles and their use for the synthesis of mononuclear and binuclear phthalocyanines

Six new halogen substituted phthalonitriles were synthesized and characterized including 4,5-diiodophthalonitrile (117a) and 3,4-diiodophthalonitrile (117b), the first of a 3,4-disubstituted phthalonitrile.; Direct bromination of phthalonitrile (3) using N,N-dibromoisocyanuric acid (120) in sulfuric acid was closely examined using HPLC. The dependence of the yields of the brominated phthalonitriles on reaction time and sulfuric acid concentration was investigated. Five bromosubstituted phthalonitriles, namely, 3-bromophthalonitrile (121), 4-bromophthalonitrile (13), 3,6-, 3,4- and 4,5-dibromophthalonitriles (122, 123, 124) were isolated from the reaction mixture and characterized, including four new compounds 121-124. Pathways of bromination were investigated utilizing HPLC and using bromosubstituted phthalonitriles as starting materials. Alternative methods for the synthesis of phthalonitriles 121 and 124 were developed. Direct bromination of 4-hydroxyphthalonitrile (17b) was investigated under similar conditions.; Six new dialkynylphthalonitriles were synthesized from disubstituted bromo- and iodophthalonitriles including five new 4,5-diallcynylphthalonitriles 132-136 and 3,4-di(3,3-dimethyl-1-butynyl)phthalonitrile (150). Phthalonitriles 132-136 were used for the preparation of 2,3,9,10,16,17,23,24-octaalkynylphthalocyanines 137-141 and their zinc derivatives 144-148. The condensation of 150 led to the formation of the single isomer, 1,2,8,9,15,16,22,23-octa(3,3-dimethyl-1-butynyl)phthalocyanine (153).; {dollar}sp1{dollar}H NMR studies of these Pcs at different concentrations and temperatures clearly demonstrate the importance of quoting concentration and temperature values when reporting {dollar}sp1{dollar}H NMR spectra of phthalocyanines. The aggregational phenomena between phthalocyanines moieties was discussed and believed to be the main cause of the downfield chemical shift of internal and aromatic protons with increasing the temperature or with decreasing the concentration of Pcs in solution.; A new single isomer binuclear 1,3-bis-2{dollar}spprime{dollar}-(9{dollar}spprime,10spprime,16spprime, 17spprime,23spprime,24spprime{dollar}-hexakis(3{dollar}sp{lcub}prime prime{rcub},3sp{lcub}primeprime{rcub}{dollar}-dimethyl-1{dollar}sp{lcub}prime prime{rcub}{dollar}-butynyl)phthalocyaninoxy)-2-ethyl-2-methylpropane (154) was synthesized from 1,3-bis-{dollar}(3spprime4sp prime{dollar}-dicyanophenoxy)-2-ethyl-2-methylpropane (73c) and 136. Unusual dependence of the chemical shifts of the aromatic and internal protons of 154 on changes in temperature was observed. Another binuclear Pc, bis{dollar}(7sp2,8sp2,12sp2,13sp2,17sp2,18 sp2{dollar}-hexakis(3{dollar}spprime,3spprime{dollar}-dimethyl-1{dollar}spprime{dollar}-butynyl)benzo (g,1,q) -5,10,15,20-tetraazaporphyrinyl) (b,f) benzene (155), was synthesized from tetracyanobenzene (50) and 136. UV-vis-IR and {dollar}sp1{dollar}H NMR spectra of 155 were useful in examining its low thermal stability.; Attempt to synthesize a binuclear Pc with an aromatic bridge resolved into the synthesis of 1,8-bis(2,3-dicyanophenyl)naphthalene (157), 1,8-diaminoanthracene (163) and 1,8-diiodoanthracene (164). A {dollar}sp1{dollar}H NMR study of bisphthalonitrile 157 showed that this compound exists as two rotamers with a very high energy of interconversion.