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Abstract Palladium‐catalyzed aryl amination and Heck arylation reactions are complementary transformations, generally requiring a suitable catalyst combination and a base. With substrates containing both an amino group and a vinyl moiety, control of C─N versus C─C reactivity can lead to regiodivergent functionalizations. With this focus, reactions of silyl‐protected 8‐vinyl 2'‐deoxyadenosine and adenosine with aryl bromides and iodides have been studied. Pd(OAc)₂, Pd₂(dba)₃, and preformed dichloro[1,1′‐bis(di‐t‐butylphosphino)ferrocene]palladium (II) (Pd‐118) were evaluated as metal sources. Ligands tested were Xantphos, DPEphos, BIPHEP, and DPPF, with Cs₂CO₃and K₃PO₄as bases. In toluene as solvent, the Pd(OAc)₂/Xantphos/Cs₂CO₃combination was uniquely capable of predominantN⁶arylation. Aryl bromides and iodides gave comparable product yields. Replacement of Cs₂CO₃with K₃PO₄redirected arylation from the nitrogen atom to the vinyl carbon atom, and all other catalyst, ligand, and base combinations gave C^vinylarylation as well. Simply switching from Pd(OAc)₂to Pd₂(dba)₃resulted in loss of theN⁶‐selectivity and C^vinylarylation was favored. Based upon these results, using two structurally similar catalytic systems sequential C^vinylandN⁶arylations of the nucleosides were accomplished. Some of the products were converted to other novel nucleoside analogues. Because some compounds were fluorescent, their photophysical properties were assessed experimentally and computationally.