Abstract
Background
.
Conclusions / Future Directions
References
Macrocycles are among the cyclic, conjugated materials that can be synthesized through various steps and procedures in order to attain its complete and stable composition. The macrocycle that we are investigating contains benzene rings alternating with boron atoms surrounded by trifluoromethyl-phenyl groups. The macrocycle B6 is the targeted product of this experiment. There are several sets of procedures and intermediates to be synthesized in order to obtain this product.
My project is to synthesize a new macrocycle compound (MC) for: electronic applications such as organic light-emitting diode (OLED) light bulbs, potential use as a catalyst, transporting formula for drug delivery, sensory materials and host guest reactions. We hypothesize that the final product, macrocycle B6, will be a special type of macrocycle. That is because boron has an empty p orbital that can accept electrons. This property is very important because it can attract electrons and can be used to improve the performance of sensory and device materials. The trifluoromethyl-phenyl groups that surround the macrocycle have electron withdrawing properties. MC B6 as a result is an electron-deficient compound which has the potential for a wide range of applications due to its ability to attract electrons.
Conjugated materials are a class of organic compounds that can be used in applications ranging from sensors to organic solar cells. There are three main types of conjugated materials: aromatic, nonaromatic and anti-aromatic compounds. An example of an aromatic compound is benzene.
Synthesis of Conjugated Oligomers: Towards Electron- Deficient Organborane Macrocycles
Cindy Gnawa, Frieder Jaekle, Ph.D, Nurcan Baser
Rutgers University-Newark
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Nine hydrogens from the trimethyl silyl group (0.30 ppm).
Two sets of hydrogen doublets (7.5 ppm and 7.3 ppm)
Column Chromatography
Common method used to purify and isolate a desired compound. It usually involves a solvent and a solid adsorbent. For our purposes, The unpurified product was purified using silica gel as the adsorbent, hexane as the solvent (eluent) and a small amount of dichloromethane to initially dissolve the product.
1H NMR (600 MHz, CDCl3) δ (ppm) 8.27 (d, J= 8 Hz, 4H), 8.16 (s, 2H), 7.65 (d, J= 8 Hz, 4H). 11B NMR (160.3 MHz, CDCl3) δ (ppm) 57.7, 66.5. 19F NMR (470.4 MHz, CDCl3) δ (ppm) -55.9 (s), -63.2 (s)
Huckel’s rule is a rule that applies to conjugated planar and cyclic molecules. The rule states that the compound needs to have 4n+2 pi electrons in the p orbitals, a loop of pi electrons, and a stable and planar structure. Aromatic compounds follow Huckel’s rule. n is usually an integer above 0 and 4n+2 pi electrons are present in the p orbitals. Anti-aromatic compounds typically have a less stable structure and they have 4n pi electrons in the p orbitals. Nonaromatic compound in some cases follow Huckel’s rule. They have a loop of pi electrons but they do not have a planar structure.
The targeted product is the macrocycle (MC - B6).There are two more sub products that need to be synthesized in order to obtain the final product. Once the macrocycle is synthesized, its electronic structure and the effect of the trifluoromethyl-phenyl groups surrounding the structure can be analyzed. It can also be tested in the future for potential applications in organic electronics and host guest chemistry.
1H NMR (600 MHz, CDCl3) δ (ppm) 8.11(s, 2H), 7.55 (q, J= 8 Hz, 8H) 0.27 (s,18H).11B NMR (160.3 MHz, CDCl3) δ (ppm) 57.0. 19F NMR (470.4 MHz, CDCl3) δ (ppm) -57.0 (s), -63.0 (s)
Figure 1: Planar cyclic benzene ring
Figure 2: Sn – Si compound reaction Procedure
Figure 3: Product
Figure 4: Proton NMR Data of the Sn – Si compound
Figure 5: BCF3 compound reaction procedure
Figure 6: Chromatography setup
Figure 7: Collected Samples
Figure 8: Silica plate under UV Lamp
Figure 9: Unpurified Product Solid
Figure 10:Purified product in crystal form
Figure 11: F-Mes BBr2
compound reaction procedure
Figure 12: NMR Data of the BBr2 compound
Figure 13:NMR Data of the F-MesB3-Br
compound
Figure 14: F-MesB3-Br
compound reaction procedure
Figure 15: Unpurified liquid
Figure 17: Purified product
Figure 18: Macrocycle B6
Methods
Methods Cont…
Figure 16: Reaction procedure