2-iodo-4-phenyl pyrimidine

The halogen metal exchange reaction between 7-bromo or 7-iodo-3-phenyltriazolopyrimidine 165 and butyllithium in iV,N,N, N -tetra-methylethylenediamine afforded the 7-lithio compound 166, whereas a similar reaction with the 7-chloro derivative 165 (R = H) gave the ring-fission product, 5-amino-l-phenyl-l//-l,2,3-triazole-4-carbonitrile 169 (91 CPB2793). Reaction of 166 with electrophiles such as benzaldehyde and ketones gave 170 and 167 respectively, together with 7,7 -bis[3-phenyl-3//-1,2,3-triazolo[4,5-d]pyrimidine] 168 (Scheme 34). 

Zinc derivatives are available by transmetallation reactions as discussed in Section 6.02.5.6.4. Most work has been done with pyridines, but coupling reactions seem equally feasible with pyrimidines. An example is provided by 2-iodo-4,6-dimethylpyrimidine which is zincated in the 2-position and Pd-coupled with iodobenzene to furnish the 2-phenyl derivative in 26% yield <93T9713). 

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