Regioselective Direct C-H Arylations of Protected Uracils. Synthesis of 5- and 6-Aryluracil Bases

0361006 - ÚOCHB 2012 RIV US eng J - Článek v odborném periodiku
Čerňová, Miroslava - Čerňa, Igor - Pohl, Radek - Hocek, Michal
Regioselective Direct C-H Arylations of Protected Uracils. Synthesis of 5- and 6-Aryluracil Bases.
Journal of Organic Chemistry. Roč. 76, č. 13 (2011), s. 5309-5319. ISSN 0022-3263. E-ISSN 1520-6904
Grant CEP: GA MŠMT(CZ) LC06077
Výzkumný záměr: CEZ:AV0Z40550506
Klíčová slova: pyrimidines * uracil * direct C-H arylations * palladium
Kód oboru RIV: CC - Organická chemie
Impakt faktor: 4.450, rok: 2011

A new regioselective synthesis of 5- and 6-aryluracil bases has been developed based on direct C-H arylations of diverse 1,3-protected uracils. Benzyl-protected uracils were selected as the most practical in terms of stability during the arylation and facile cleavage of the benzyl groups. Pd-catalyzed C-H arylations in absence of CuI gave preferentially 5-aryl-, whereas the reactions in presence of CuI gave 6-aryl-1,3-dibenzyluracils. Final deprotection either by transfer hydrogenolysis over Pd/C or by treatment with BBr3 gave the desired free arylated uracil bases in good yields.
Trvalý link: http://hdl.handle.net/11104/0198426