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Updated: Apr 20, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Recyclization reactions of 1-alkylpyrimidinium salts
Ruben S Vardanyan1, Gevork G Danagulyan2, Armen D Mkrtchyan2
1Departments of Chemistry and Biochemistry, 1306 University Boulevard, University of Arizona, Tucson, AZ 85721, USA.
Abstract:
The reaction of 4-amino-2-benzyl-1-methyl-5-ethoxycarbonylpyrimidinium iodide (3) with alcoholic methylamine resulted in the formation of the methylimine of 2-amino-4-hydroxy-6-methylamino-5-phenylpyridine-3-carbaldehyde (5). Heating of the same pyrimidinium salt in benzylamine gave a mixture of products of two C-C recyclizations: 2-benzyl-4-benzylamino-5-carbamoylpyrimidine (7) and the benzylimine of 4-amino-2-benzyl-6-benzylaminopyrimidine-5-carbaldehyde (8). The reaction of 2-amino-1,4-dimethyl-5-ethoxycarbonylpyrimidinium iodide (10) with KOH ethanolic solution gave a single product of C-C-recyclization: 2-amino-5-acetyl-4-hydroxypyrimidine (11).
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