Synthesis of a peralkynylated pyrazino[2,3-g]quinoxaline.
[structure: see text] The synthesis of a hexaethynyl[2,3-g]pyrazinoquinoxaline and its crystal structure are reported. Starting from tetraaminobenzoquinone, condensation to bis(triisopropylsilyl)hexadiyne-2,3-dione affords 2,3,7,8-tetrakis(triisopropylsilylethynyl)pyrazino[2,3-g]quinoxaline-5,10-dione. Reaction with TIPS-CC-Li followed by reduction with hypophosphite in the presence of KI furnished the title molecule in a yield of 62%. Pd catalysis is not involved in any of these steps.
Miao
Shaobin
S
School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
Smith
Mark D
MD
Bunz
Uwe H F
UH