Category
Theoretical Proposal
Description
Nitrosobenzenes (NBs) are benzene structures containing a nitroso functional group and are observed to be both monomer and E/Z dimer. NB is capable of dimerizing into azodioxides, but dimerization is generally limited to NBs with electron withdrawing groups (EWG). The EWG pulls electrons towards itself, reducing NBs electron density. This reduces resonance through the NB, disfavoring the formation of a quinoidal structure, which inhibits dimerization. This reduced electron density increases the potential for dynamic covalent bonding (DCB), leading to dimerization. However, NBs with electron donating groups (EDG) do form quinoidal structures (through resonance). This quinoidal form prevents DCB, which ultimately inhibits dimerization. Our research question is, “Can we create a system in which we can have total control over monomerization and dimerization, by addition or removal of an electron? Phase one of our work has been the attempted synthesis of our target compound (redox auxiliary appended nitrosobenzene), using two reagents: 4-chloronitrosobenzene, and our redox auxiliary group (RAG), dianisylamine. To synthesize our target compound, we have utilized a technique known as nucleophilic aromatic substitution (SNAr), using an instrument known as a microwave reactor. We also plan to also utilize another synthetic pathway known as the Buchwald Hartwig reaction, if SNAr is unsuccessful. Upon successful synthesis and analysis our target compound, (via NMR and IR spectroscopy, Mass spectrometry, and Thin Layer Chromatography), we plan to electronically induce dimerization. However, dimerization will initially not be favored, since the RAG will contain an EDG (methoxy). We hypothesize that reducing the electron density of our target compound could promote dimerization. By creating a radical cation on the central dianisylamine (An2N) nitrogen, electron density decreases, promoting dimerization even with an EDG. Phase two of our work will be to synthesize our oxidizing agent, CRET. We will use CRET as our tool to create this radical cation. If successful, we would exhibit the ability to toggle between monomer and dimer, simply by changing the electron density of the system. Since NBs are used as starting materials in many synthetic pathways, control over dimerization could prove useful.
Preparation a Redox Auxiliary Appended Nitrosobenzene
Theoretical Proposal
Nitrosobenzenes (NBs) are benzene structures containing a nitroso functional group and are observed to be both monomer and E/Z dimer. NB is capable of dimerizing into azodioxides, but dimerization is generally limited to NBs with electron withdrawing groups (EWG). The EWG pulls electrons towards itself, reducing NBs electron density. This reduces resonance through the NB, disfavoring the formation of a quinoidal structure, which inhibits dimerization. This reduced electron density increases the potential for dynamic covalent bonding (DCB), leading to dimerization. However, NBs with electron donating groups (EDG) do form quinoidal structures (through resonance). This quinoidal form prevents DCB, which ultimately inhibits dimerization. Our research question is, “Can we create a system in which we can have total control over monomerization and dimerization, by addition or removal of an electron? Phase one of our work has been the attempted synthesis of our target compound (redox auxiliary appended nitrosobenzene), using two reagents: 4-chloronitrosobenzene, and our redox auxiliary group (RAG), dianisylamine. To synthesize our target compound, we have utilized a technique known as nucleophilic aromatic substitution (SNAr), using an instrument known as a microwave reactor. We also plan to also utilize another synthetic pathway known as the Buchwald Hartwig reaction, if SNAr is unsuccessful. Upon successful synthesis and analysis our target compound, (via NMR and IR spectroscopy, Mass spectrometry, and Thin Layer Chromatography), we plan to electronically induce dimerization. However, dimerization will initially not be favored, since the RAG will contain an EDG (methoxy). We hypothesize that reducing the electron density of our target compound could promote dimerization. By creating a radical cation on the central dianisylamine (An2N) nitrogen, electron density decreases, promoting dimerization even with an EDG. Phase two of our work will be to synthesize our oxidizing agent, CRET. We will use CRET as our tool to create this radical cation. If successful, we would exhibit the ability to toggle between monomer and dimer, simply by changing the electron density of the system. Since NBs are used as starting materials in many synthetic pathways, control over dimerization could prove useful.
