Research On Synthesis And Properties Of 2-Amine Aromatic Ketone Photoinitiators

There has been a history of seventy years of UV curing technology, which applied for a patent application for the first time since the 1940 s to the present applications in coatings, inks, adhesives and electronic circuit boards and other fields. As the core technology, the photoinitiator of the research and development has a rapid development. Based on aminoketones photoinitiator 907 as the research object, this paper firstly did a simple overview of the development of UV curing technology at home and abroad. For the defects of other synthetic routes, this paper proposed a new synthesis of the process of photoinitiator 907, and did a lot of work of the optimization of the process route. Thereafter, on the basis of the process routes, we changed the substrate of the initial reaction and used benzene, toluene and chlorobenzene as substrate to synthesis of novel photoinitiators. In exploratory experiments, we still used benzene, toluene and chlorobenzene as a substrate, at the same time changed the raw material of the amine substitution reaction instead of diethylamine and piperidine to synthesize of six kinds of novel photoinitiators with the use of the process route and did simple optimization work of these experiments. Finally, this paper made a photoinitiator performance testing.(1)Synthesis of 1-(4-methyl sulfonium phenyl)-2-2-methyl bromide-acetone to optimize conditions for:n (methyl phenyl sulfide):n(aluminum chloride)=1:1.3, the reaction temperature was 20℃, the reaction time was 3 hours.In the optimized conditions, we could make the reaction yield reach 92%. Synthesis of 2-methyl-1-[4-(methyl thio) phenyl]-2-(4-morpholine)-1-acetone to optimize conditions for:n (1-(4-methyl sulfonium phenyl)-2-2-methyl bromide-acetone:n(morpholine)=1:3, n(1-(4-methyl sulfonium phenyl)-2-2-methyl bromide-acetone):n(aluminum chloride)=1:0.1, reaction using petroleum ether as solvent.On the optimal conditions, the yield can reach 92%.(2)The friedel-crafts reaction of optimum process optimization condition for: n(benzene and monosubstituted BTEX)):n(chloride)=1:1.3, benzene and toluene as the substrate of the friedel-crafts reaction of the best reaction time was 3h, with chlorobenzene as substrate the friedel-crafts optimal reaction time was 4h, the three optimal reaction temperature was 20℃, and the stability experiment, the average yield of the three could separately reach 91.2%,90.8%,90.0%. Amino substitution reaction of best optimizing process conditions as follows:the optimum reaction time for 5h, n(bromine intermediates):n (morpholine)=1:3, under the condition of the reaction yield can reach 89%.(3) The zetetic experiment:2-bromide intermediates reaction with diethylamine, the optimization conditions of the three reactions was in the feed ratio of 1:3, the reaction time was 16h, three reactions yield were separately 80.5%,79.7% and 80.1%, respectively.2-bromide intermediates reaction with piperidine, the optimal conditions for the three reactions were that the optimal reaction temperature was 40 ℃, the best reaction feeding ratio of n(2-bromide):n(piperidine)=1:1.5. Under the optimal process conditions, the three reaction yield was 73.1%,75.1% and 71.9%, respectively. The structure of substances which were obtained by the route of synthesis has got structure validation by NMR and MS.(4) Photoinitiated performance test:We tested several samples, but photoinitiator performance of all products was not as good as the performance of the standard. Photoinitiator performance under anaerobic environment was better than under aerobic conditions.The photoinitiator performance of 1-phenyl-2-methyl-2-diethylamino-1-acetone was the worst, photoinitiator performance of other products has basically little difference.