Synthesis of Quinazolinediones
A tandem palladium-catalyzed arylation-ester amidation sequence allows the synthesis of various quinazolinedione products by reaction of o-halo benzoates with monoalkyl ureas. The reactions are regioselective for the formation of 3-N-alkyl isomers.
M. C. Willis, R. H. Snell, A. J. Fletcher, R. L. Woodward, Org. Lett., 2006, 8, 5089-5091.
An efficient method for the synthesis of disubstituted quinazoline diones with differential N-substitution proceeds in high yields under mild conditions. The reaction tolerates a wide range of substitutions on the aromatic and dione rings.
E. Durham, D. Perkins, J. S. Scott, J. Wang, S. Watson, Synlett, 2016, 27, 965-968.
A Pd-catalyzed insertion and cycloaddition of CO2 and isocyanide to 2-iodoanilines provides quinazoline-2,4(1H,3H)-diones under mild conditions through the formation of C-C, C-O, and C-N bonds.
P. Xu, F. Wang, T.-Q. Wei, L. Yin, S.-Y. Wang, S.-J. Ji, Org. Lett., 2017, 19, 4484-4487.
XANTPHOS has been identified as the optimal ligand for a nickel(0)-catalyzed synthesis of quinazolinediones from isatoic anhydrides and isocyanates. Preliminary results on an asymmetric synthesis of atropisomeric quinazolinediones are reported too.
G. L. Beutner, Y. Hsiao, T. Razler, E. M. Simmons, W. Wertjes, Org. Lett., 2017, 19, 1052-1055.