Synthesis of d- and p-Block Element Molecules, Reagents, and Precursors

With support from the Chemical Synthesis Program of the Chemistry Division, Professor Christoper Cummins of the Chemistry Department at the Massachusetts Institute of Technology (MIT), is synthesizing phosphorus-containing small molecules that may have relevance to the identification of interstellar molecules. The project resides at the intersection of synthetic chemistry and astrochemistry. Chemical synthesis will be used to prepare small molecules that may exist in interstellar space. Their characterization in the laboratory will pave the way for astrophysicists to search for them in space. In reciprocal fashion, known interstellar molecules serve as inspiration for the development of new, highly reactive species that can be developed as new reagents in synthetic chemistry. The project also is expected to have impacts on materials science in that some of the new small molecules and their molecular precursors may provide low-temperature access to inorganic materials of interest for their electronic properties. Reagents developed in the course of the project may find application in organic synthesis and catalysis. Additionally, the project will educate and train a diverse group of undergraduate and graduate students, and postdoctoral scholars. Broader impacts also include outreach through the MIT Access program aimed at bringing members of underrepresented groups into graduate study in chemistry, and the planned production of YouTube “Inorganic Synthesis Videos.” The project has a theme of design and synthesis of anthracene-based reagents for generating novel reactive intermediates for group transfer reactions in solution, or for evolution of small molecules into the gas phase for study by molecular beam mass spectrometry and microwave spectroscopy. The latter form of spectroscopy is used to collect the data required by the radio astronomers to make a positive identification of the molecules in interstellar space. Specific systems to be investigated include triphosphatetrahedrane, phosphorus mononitride (PN) and non-explosive synthons to it, molecular precursors to PNSO, synthesis and chemistry of phosphiranes (derivatives of C2H4PH), and RBA and REA Compounds (R = alkyl; E = N or P; A = anthracene). The project also will involve the development of transition-metal catalyzed reactions for group transfer to organic substrates, such as olefins. One line of inquiry will explore the ramifications of strain energy release-driven catalysis involving strained molecules known as phosphatetrahedranes. The project involves a number of collaborations, perhaps most notably with astrophysicists interested in investigating interstellar molecules. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.