SOAR Research Proposal -- Fall 2005

Synthesis and Reactions of 1-Aminoazulene: A Possible Visual Metal-ion Indicator.

Faculty: Carl Salter Associate Professor of Chemistry

Student: Caitlin Benfield Junior Chemistry major 3.45 GPA overall, 3.33 GPA in major stcnb01@moravian.edu.

Description:

Synthesis and Reactions of 1-Aminoazulene: A Route to Possible Visual Metal-ion Indicators. One area of interest in modern chemistry is the synthesis and characterization of molecules that can act as sensors or “molecular reporters” for the presence of other chemical species. Such molecules have important applications in medicine, biology, and environment chemistry. The most useful molecular reporters are those that change their properties with respect to visual light, because it is easy to develop probes and instruments involving light.

One molecule that has a significant interaction with light is azulene. Azulene, a remarkably simple hydrocarbon, is intensely blue; a derivative of azulene is used in bath soaps to color the bubbles blue. Because very small concentrations of azulene can be detected with visual light, azulene could be the basis for a molecular reporter. The reason why it has not been exploited for this purpose is because the reaction chemistry of azulene is unusual, and azulene is rather expensive: $100/gram. However, recently there has been renewed interest in the chemistry of azulene, even in the teaching literature of chemistry, and new ways of working with azulene may make it possible to use it as the basis of a molecular reporter.

The key to making derivatives of many compounds is to add an –NH₂ group, called an amino group, to the molecule, because many reactions become possible once an amino group is in place. The scheme shown on the next page indicates a route to 1-aminoazulene and one derivative that could potentially bind to metal ions.

Roles:

Caitlin Benfield should be able to work on the project on Thursday and Friday each week for a total of eight hours per week. I am free on Thursday afternoons so that I can work with her on the project. Caitlin’s role will be to run a reaction and perform tests on the result to determine whether the desired product was obtained. My role will be to help her interpret the results of the tests, and to suggest alternative ways to achieve the desired reaction. The first step, nitration (-NO₂), has been done before, so by the third week Caitlin should have plenty of nitroazulene on hand. Then she can start attempting the conversion of the nitro group to the amino group using via finely divided metal, either zinc or tin, as a reducing agent. Start date: Sept 5. Stop date Dec 2.

Benefits:

Caitlin will gain experience doing synthetic chemistry and running tests on organic compounds. In particular, she will have an opportunity to run the NMR instrument, which she enjoyed during her organic class this year. I will benefit from having a student who has the time to try out these ideas on the color chemistry of azulene. The molecular reporter aspect of the project means that, if we can get to the key intermediate aminoazulene, funding for the remainder of the project could be obtained from external grant organizations such as PRF or Research Corporation. Such external funding will allow the College to expand student participation in its summer research program without using College funds.

Budget:

The only budget request is the $850 for Caitlin’s stipend. Azulene and other materials will be supplied by the chemistry department.

Synthetic scheme

Possible derivative that could bind a metal ion:

Aminoazulene diacetic acid