On the base of benzimidazole and benzofuran containing heterocyclic system, several derivatives with expected biological activity were synthesized. 2,3-diaminodibenzofuran was the primary substance. Adding various cyc...On the base of benzimidazole and benzofuran containing heterocyclic system, several derivatives with expected biological activity were synthesized. 2,3-diaminodibenzofuran was the primary substance. Adding various cyclic agents, 2-phenil was got, 2-（o-chlorophenil）, 2-（o-oxyphenil）, 2-chlorometyl- and 2-hydroximethyl-3H-benzo[b[furo（3,2-f] benzimidazoles. The aforementioned substances were characterized by IR and NMR spectroscopy.展开更多
Pyrrolo[3,2-b]pyrrole is a good building block for radical photoini-tiators.In this study,free-radical photoinitiator 1,4-bis(4-bro-mophenyl)-2,5-bis(4-(trifluo-romethyl)phenyl)-1,4-dihydropy-rrolo[3,2-b]pyrrole(PyBF)...Pyrrolo[3,2-b]pyrrole is a good building block for radical photoini-tiators.In this study,free-radical photoinitiator 1,4-bis(4-bro-mophenyl)-2,5-bis(4-(trifluo-romethyl)phenyl)-1,4-dihydropy-rrolo[3,2-b]pyrrole(PyBF),con-taining a symmetric trifluo-romethyl(-CF3)end group,is syn-thesized via a one-step aldehyde-ketone condensation re-action for light-emitting diode(LED)photopolymerization.The-CF3 groups are incorporated into the 2,5-phenyl on the pyrrolo[3,2-b]pyrrole core.PyBF rapidly initiates the photopolymerization of acrylate pre-polymers and monomers under LED illumination at 365 and 405 nm.A possible photolysis mechanism is provided.In the presence of amines,PyBF increases the gel fraction rate of polyethylene glycol diacrylate(PEGDA)from 63.4%to 80.0%,indicating good potential as a two-component photoinitiator.PyBF exhibits a thermal decomposition temperature in an ex-cess of 300℃,comparable to that of a commercial photoinitiator(diphenyl(2,4,6-trimethyl-benzoyl)phosphine oxide,TPO),indicating its thermal stability.PyBF shows low migration in light-curing materials.Scanning electron microscopy images indicate that the materials of the PyBF/TPO/PEGDA mixture cured using the PyBF/TPO two-component photoinitia-tor system exhibit a smooth surface,in contrast to those cured with PyBF/PEGDA and TPO/PEGDA systems.The cured materials also display low curing shrinkage.Therefore,the pyrrolo[3,2-b]pyrrole radical photoinitiator exhibits high photoactivity in visible-light pho-topolymerization reactions.展开更多
文摘On the base of benzimidazole and benzofuran containing heterocyclic system, several derivatives with expected biological activity were synthesized. 2,3-diaminodibenzofuran was the primary substance. Adding various cyclic agents, 2-phenil was got, 2-（o-chlorophenil）, 2-（o-oxyphenil）, 2-chlorometyl- and 2-hydroximethyl-3H-benzo[b[furo（3,2-f] benzimidazoles. The aforementioned substances were characterized by IR and NMR spectroscopy.
基金the financial support of the Tianjin Technical Expert Project(22YDTPJC00620)。
文摘Pyrrolo[3,2-b]pyrrole is a good building block for radical photoini-tiators.In this study,free-radical photoinitiator 1,4-bis(4-bro-mophenyl)-2,5-bis(4-(trifluo-romethyl)phenyl)-1,4-dihydropy-rrolo[3,2-b]pyrrole(PyBF),con-taining a symmetric trifluo-romethyl(-CF3)end group,is syn-thesized via a one-step aldehyde-ketone condensation re-action for light-emitting diode(LED)photopolymerization.The-CF3 groups are incorporated into the 2,5-phenyl on the pyrrolo[3,2-b]pyrrole core.PyBF rapidly initiates the photopolymerization of acrylate pre-polymers and monomers under LED illumination at 365 and 405 nm.A possible photolysis mechanism is provided.In the presence of amines,PyBF increases the gel fraction rate of polyethylene glycol diacrylate(PEGDA)from 63.4%to 80.0%,indicating good potential as a two-component photoinitiator.PyBF exhibits a thermal decomposition temperature in an ex-cess of 300℃,comparable to that of a commercial photoinitiator(diphenyl(2,4,6-trimethyl-benzoyl)phosphine oxide,TPO),indicating its thermal stability.PyBF shows low migration in light-curing materials.Scanning electron microscopy images indicate that the materials of the PyBF/TPO/PEGDA mixture cured using the PyBF/TPO two-component photoinitia-tor system exhibit a smooth surface,in contrast to those cured with PyBF/PEGDA and TPO/PEGDA systems.The cured materials also display low curing shrinkage.Therefore,the pyrrolo[3,2-b]pyrrole radical photoinitiator exhibits high photoactivity in visible-light pho-topolymerization reactions.
