Unexpected Formation and X-ray Structure of Tetramethyl 4,5-bis(dimethylamino)-2,3,6,7-tetra-azaocta-1,3,5,7-tetraene-1,1,8,8-tetracarboxylate [c16h24n6o8] From Bis(dimethylamino)acetylene and Dimethyl Diazomalonate

Tinant, B., Declercq, J.-P., Van Meerssche, M., Bouvy, A., Janousek, Z., & Viehe, HG. (1985). Unexpected Formation and X-ray Structure of Tetramethyl 4,5-bis(dimethylamino)-2,3,6,7-tetra-azaocta-1,3,5,7-tetraene-1,1,8,8-tetracarboxylate [c16h24n6o8] From Bis(dimethylamino)acetylene and Dimethyl Diazomalonate. Royal Society of Chemistry. Journal: Perkin Transactions 2, 9, 1419-1421. https://doi.org/10.1039/p29850001419 (Original work published 1985)