Preparation of Polyfunctionalized 2,6-Dimethoxypyrimidine Derivatives via Chemo- and Regioselective Direct Zinc Insertion

Abstract

The functionalization at the C4 and/or C5 positions of 2,6-dimethoxypyrimidine derivatives via direct chemo- and regioselective zinc insertions is described. The insertion of commercially available zinc dust into C-I and C-Br bonds, in the presence of LiCl, proceeded under mild reaction conditions. The reactions of the resulting organozinc reagents with electrophiles gave the expected products in good yields. This procedure represents a new method for the polyfunctionalization of uracil derivatives.

Key words

insertion - organozinc compounds - zinc - pyrimidine - uracil

References

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12

Conversion >98%; the reaction conversion was monitored by GC-analysis of hydrolyzed reaction aliquots quenched with aq NH₄Cl.

14

Boudet, N. The preparation of this starting material will be published soon elsewhere.