Synthesis of N-alkenylpurines by rearrangements of the corresponding N-allyl isomers: Scopes and limitations

Abstract

N-9- and N-7-alkenylpurines have been synthesized by rearrangement of the corresponding N-allyl derivatives, often in good yields and with high stereoselectivity. Base promoted and transition metal mediated rearrangements have been studied. Simple allylpurines were easily rearranged with catalytic amounts of RuClH(CO)(PPh3)3. The efficiency of base promoted rearrangement was highly dependent on the detailed structure of the starting material, but this reaction often occurred with surprisingly high Z-selectivity. N-Alkenylpurines have been synthesized, often in good yields, from the corresponding more readily available N-allyl isomers by a double bond migration. The scope and limitation of the rearrangement in the presence of various bases or transition metal complexes have been studied. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.