One-Pot Synthesis of 5-Methyl-3H-pyrrolo[2,3-d]pyrimidin-4(7H)-one

An efficient and environmentally benign synthesis of 5-methyl-3H-pyrrolo[2,3- d ]pyrimidin-4(7H)-one is described. An acyl-protected aminoacetone is reacted with cyanoacetamide to give 2-amino-4-methyl-1H-pyrrole-3-carboxamide, which is converted in one-pot to 5-methyl-3H-pyrrolo[2,3- d ]pyrimidin-4(7H)-one in 60% overall yield. This process avoids the use of large excess Raney nickel which is required when known methods are practiced.