Fischer-Dimroth rearrangement

Figure 1.54 Alkylation reactions can occur at the N-l position of adenosine, resulting in a Fischer-Dimroth rearrangement to yield an Ng derivative.

Adenine also may undergo an additional reaction at its C-6 amine group using a Fischer-Dimroth rearrangement mechanism. Alkylation at N-l can result in a rearrangement to give the C-6 alkylated product. The reaction at N-l usually requires... 

Fischer and Misun used the Dimroth rearrangement in their preparative synthesis of CGP-59326, a pyrrolo[2,3- flpyrimidine that has also been investigated as an EGFR inhibitor. Compound 125, prepared in four steps from commercially available alanine, was readily converted to CGP-59326 in 92% yield in the presence of a mixture of refluxing ethylene glycol, ethanol and water. 

---