39175-16-1Relevant academic research and scientific papers
Ortho-lithiations reassessed: The advantages of deficiency catalysis in hydrocarbon media
Slocum,Reinscheld, Thomas K.,White, Christopher B.,Timmons, Michael D.,Shelton, Philip A.,Slocum, Matthew G.,Sandlin, Rebecca D.,Holland, Erica G.,Kusmic, Damir,Jennings, John A.,Tekin, Kristen C.,Nguyen, Quang,Bush, Steven J.,Keller, Julia M.,Whitley, Paul E.
, p. 1674 - 1686 (2013/05/08)
Hydrocarbon media based metalation procedures involving "deficiency catalysis" are described for the ortho-lithiation of anisole (A), p-chloroanisole (p-ClA), o-, m-, p-methylanisoles (o-, m-, p-MA), the three dimethoxybenzenes (DMB's), dimethylaniline (DMA), dimethybenzylamine (DMBA), m-methoxydimethylaniline (m-MeODMA), and tetramethyl-p-phenylenediamine (p-TMPDA). These procedures involve certain mechanistic considerations, which must be fine-tuned to maximize the extent of metalation (EoM). Our working hypothesis is that a controlled deoligomerization of the n-BuLi hexamer found in hydrocarbon media will afford a "sweet spot" of deoligomerization such that a maximally efficient metalation medium can be formed. In many cases, a substoichiometric ratio of equivalent TMEDA to n-BuLi is 0.1-0.2:1.0, but certain substrates suffer multiple sites of metalation under these conditions, so different promoted hydrocarbon media systems incorporating measured equivalents of an ether have been formulated. This paper represents the summary of our successful efforts to render ortho-lithiations safer, greener, and more atom-economical by use of hydrocarbon solvent media. EoM's of 11 of the 12 substrates under these atom-economical conditions range from 87 to 97%.
Emissive multichromophoric systems
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, (2008/06/13)
Synthetic multichromophoric systems exhibiting low energy fluorescent excited states in which the transition dipoles of the pigment building blocks are correlated in defined phase relationships are provided. The polarized nature of these singlet excited s
Ring-metalated porphyrins
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, (2008/06/13)
Reaction products comprising ring-metalated porphyrins are provided that are useful in the synthesis of porphyrin polymers and porphyrins substituted with, for example, vinyl and acetylene groups.
Substituted porphyrins, porphyrin-containing polymers, and synthetic methods therefor
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, (2008/06/13)
Porphyrins substituted with, for example, vinyl and acetylene groups are provided, along with polymers containing the same. In preferred embodiments, the substituted porphyrins are prepared by coupling halogenated porphyrins with carbon-centered anionic g
