Beginning Question: How effectively and efficiently can biphenyl be synthesized by a Suzuki coupling reaction?
Claims: Biphenyl synthesized by a Suzuki coupling reaction was effectively isolated and then characterized using TLC, melting point, IR and 1H NMR tests. However, this process was not efficient because it had a poor pure yield of 22%. Evidence: The goal of the experiment was to synthesize biphenyl product by a Microwave-assisted Suzuki reaction and this was carried out using 1 equivalent bromobenzene, 1 equivalent phenylboronic acid, 1.3 x 10-2 equivalent Pd(OAc)2, 3.0 equivalents Na2CO3, and 0.25 equivalent TBAB (Figure 1). All starting reagents were combined in a microwave tube and the water solvent was added just before the reaction vessel was sealed to be superheated in the microwave. The microwave was used as a fast heat source and at high pressures, the reaction can be superheated to temperatures beyond the normal boiling point of the solvent. This heat was responsible for converting the Pd(OAc)2 pre-catalyst into active Pd(0) catalyst, which was then able insert between the benzene-bromide bond of bromobenzene in the oxidative addition step of the Suzuki reaction. For the following transmetallation, the Na2CO3 base first …show more content…
National Library of Medicine). However, since the melting point range did not completely align, it could be helpful to also look at the melting point of benzene, which was another potential byproduct. Benzene byproduct would have been formed by the protonolysis of the bromobenzene after oxidative addition or by the protodeboronation of the phenylboronic acid. The established melting point of benzene is 80°C, which deviated even more from the observed melting point (U.S. National Library of Medicine). From this test, it was also safe to assume that biphenyl is most likely the product we
Claims: Biphenyl synthesized by a Suzuki coupling reaction was effectively isolated and then characterized using TLC, melting point, IR and 1H NMR tests. However, this process was not efficient because it had a poor pure yield of 22%. Evidence: The goal of the experiment was to synthesize biphenyl product by a Microwave-assisted Suzuki reaction and this was carried out using 1 equivalent bromobenzene, 1 equivalent phenylboronic acid, 1.3 x 10-2 equivalent Pd(OAc)2, 3.0 equivalents Na2CO3, and 0.25 equivalent TBAB (Figure 1). All starting reagents were combined in a microwave tube and the water solvent was added just before the reaction vessel was sealed to be superheated in the microwave. The microwave was used as a fast heat source and at high pressures, the reaction can be superheated to temperatures beyond the normal boiling point of the solvent. This heat was responsible for converting the Pd(OAc)2 pre-catalyst into active Pd(0) catalyst, which was then able insert between the benzene-bromide bond of bromobenzene in the oxidative addition step of the Suzuki reaction. For the following transmetallation, the Na2CO3 base first …show more content…
National Library of Medicine). However, since the melting point range did not completely align, it could be helpful to also look at the melting point of benzene, which was another potential byproduct. Benzene byproduct would have been formed by the protonolysis of the bromobenzene after oxidative addition or by the protodeboronation of the phenylboronic acid. The established melting point of benzene is 80°C, which deviated even more from the observed melting point (U.S. National Library of Medicine). From this test, it was also safe to assume that biphenyl is most likely the product we