Studies On The Baylis-Hillman Reaction Of Acrylamide And Synthesis Of Several Chemical Intermediates

Part 1. The Baylis-Hillman Reaction of AcrylamideThe Baylis-Hillman reaction, the coupling of α, β-alkenes with carbon electrophiles under the catalysis of tertiary amines, is emerging as valuable carbon-carbon bond forming reaction.The reaction has drawn increasing attention because it is selective (chemo-, region-, diastereo-, enantio-), atom economical, and produces synthetically useful functionalized molecules under relatively mild conditions.During the α, β-alkenes, acrylamide and its derivates are important acrylamido monomers for producing polymers and the reagents for biological application and drug design. So the synthesis of its derivates through Baylis-Hillman reaction is necessary. It is hard to react with aldehydes under ambient conditions because of it is usually thought to be weak Michael acceptor. Firstly, N-aryl acrylamides were found to be the more activated Michael acceptor than acrylamide for Baylis-Hillman reaction. The desired Baylis-Hillman products, α-Substituted acrylamide derivatives which have important application as novel radical polymerization monomers and biologically important reagents, can be obtained through the reaction of N-arylacrylamides with aromatic aldehydes in the presence of DABCO in this paper. Secondly, we activated aromatic aldehydes to N-tosylated imines, then studied its Bayli-Hillma reaction with acrylamide and N-aryl acrylamides. Through our reseach ,we found this Bayli-Hillma reaction could undergo easily in the presence of DABCO and phenol. In addition, their yieds are very high and reaction times are short Compared with the common Bayli-Hillma reaction.Part 2. The Preparations of several organic intermediates(1) Adding unnatural amino acids to the structure of peptides and circle peptides in order to gain similar peptides whose structures are modified. They are widely used in super molecular chemistry and medicines. So the prepare of these unnatural amino acids compared with common aminoacids is very important. Wu used Phenethylamine as the raw material synthesized two unnatural amino acids: p-(aminoethyl)-benzoic acid and p-(aminoethyl)-phenylacetic acid. It Based for the synthesis of new similar peptides.(2) 2-Nitrobenzaldehyde and its derivatives are important fine chemical intermediates. They are applied to medicines and dyes widely. Otherwise, if the fluorin is added to benzene ring, it can promote the polish and beautiful color of dyes,also can increase lightfast and waterfast. It can promotes biologic activity and medical efficiency if it is added to medicines and pesticides. So we prepared the chemical intermediate of 4-fluoro-2-nitrobenzaldehyde.(3) Alkyl pyridine is also important intermediate, it is also applided to medicines, pesticides, dyes, flavors and other additives widely. So we synthesized the pruduct of 4-fluoro-2-methylpyridine easily from 2-methylpyridine-N-oxide.(4) Diquat is the largest Herbicide except for glyphosate and paraquat. There are so many methods for preparation of it. In this paper we synthesized diquat without solvents and catalysts from 2, 2'-dipyridine and 1,2-dibromoethane. Furthermore, its quotiety is considerable. Thus we can save many solvents and lots of money. So this method provides basis for craftworks optimization.(5) Substituted Phenethylamines are important intermediates in organic synthesis. They are absent because of their low quotieties. So the synthesis of Substituted Phenethylamines are considered very important. In this paper we synthesized several derivatives, provided several means for the synthesis of them.(6) Pyridine and its derives are very critical intermediates. An easy method is provided for synthesis of 3-methoxypyridine in this paper. Moreover, its quotiety and purity are optically high.