A practical synthesis of 5-functionalized thieno[2,3-d]pyrimidines
摘要:
The synthesis of 5-hydroxymethyl-, 5-acetoxymethyl-, 5-formyl- and 5-cyanothieno[2,3-d]pyrimidines, the (methyl)-5-carboxylate, and the respective amide functionality was accomplished by building up the functionalized molecule starting from appropriately substituted thiophene precursors. A similar strategy starting from the pyrimidine precursor and subsequent direct functionalization (formylation and cyanation) of the thieno[2,3-d]pyrimidine parent compound in position 5 was found to be less feasible. (C) 2015 Elsevier Ltd. All rights reserved.
Regioselective Metalations of Pyrimidines and Pyrazines by Using Frustrated Lewis Pairs of BF<sub>3</sub>⋅OEt<sub>2</sub>and Hindered Magnesium- and Zinc-Amide Bases
作者:Klaus Groll、Sophia M. Manolikakes、Xavier Mollat du Jourdin、Milica Jaric、Aleksei Bredihhin、Konstantin Karaghiosoff、Thomas Carell、Paul Knochel
DOI:10.1002/anie.201301694
日期:2013.6.24
Born of frustration: Using the frustratedLewispairs TMP–metal and BF3⋅OEt2 allows the regioselectivemetalation of pharmaceutically relevant diazines, such as pyrimidines, purines, and pyrazines. These metalations are often complementary to prior deprotonations performed without BF3⋅OEt2. Especially attractive is a new sequential regioselective full functionalization of the pyrazine scaffold with a bulky