1. Ethynylated Acene Synthesis and Photophysics for an Organic Chemistry Laboratory Course
- Author
-
Anthony J. Petty and Susan A. Odom
- Subjects
chemistry.chemical_classification ,010405 organic chemistry ,Silica gel ,05 social sciences ,Diol ,050301 education ,Alkyne ,General Chemistry ,01 natural sciences ,Fluorescence spectroscopy ,0104 chemical sciences ,Education ,Quinone ,chemistry.chemical_compound ,Ultraviolet visible spectroscopy ,chemistry ,Molecule ,Organic chemistry ,0503 education ,Acene - Abstract
An operationally simple, reliable synthesis of ethynylated acenes suitable for an upper-division undergraduate organic chemistry laboratory course has been developed. This experiment requires students to synthesize two acene derivatives and can be completed in 6–8 laboratory sessions (3 h each); a shorter experiment could be realized in the synthesis of only one product. Synthesis is carried out by first treating a terminal alkyne with n-butyllithium in an oven-dried flask under nitrogen at 0 °C. An acene quinone is added, which produces a doubly ethynylated diol. Dehydration with SnCl2/HCl yields a bis(ethynylated) acene, which is purified via a short pad or column of silica gel. The intense colors of the products allow for great ease in determining reaction completion and following the products in chromatography. UV–vis and fluorescence spectroscopy may be used to better understand the effect of molecular structure on electronic properties.
- Published
- 2021