The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Derivatives of pyridine and quinoline. LII. Synthesis of 2,4-dimethyl-3-hydroxy-5-(hydroxymethyl)pyridine (4-desoxyadermine)》. Authors are van Wagtendonk, H. M.; Wibaut, J. P..The article about the compound:5-(hydroxymethyl)-2,4-dimethylpyridin-3-ol hydrochloridecas:148-51-6,SMILESS:OC1=C(C)C(CO)=CN=C1C.[H]Cl).Reference of 5-(hydroxymethyl)-2,4-dimethylpyridin-3-ol hydrochloride. Through the article, more information about this compound (cas:148-51-6) is conveyed.
cf. C. A. 35, 5112.3. NCCH2CONH2 and CH2Ac2 with piperidine in EtOH at 80° give 87% of 4,6-dimethyl-3-cyano-2-pyridone (I), m. 293° (corrected); with HNO3 (d. 1.52) in Ac2O at 5°, I gives a crude yield of 40-6% of the 5-NO2 derivative which with PCl5 in PhCl gives 24-8% of 2,4-dimethyl-3-nitro-5-cyano-6-chloropyridine (II), yellow, m. 114-15°. Catalytic reduction of II with Pd-C in 96% EtOH gives 81.4% of 2,4-dimethyl-3-amino-5-cyano-6-chloropyridine, m. 149-9.2° (corrected); further reduction with Pd-C catalyst in AcOH-AcONa at room temperature gives 2,4-dimethyl-3-amino-5-(aminomethyl)pyridine, characterized as the dipicrate, m. 244° (decomposition), and the di-HCl salt (III), with 1 mol. H2O, does not m. 300°. Reaction of III in 2 N H2SO4 with NaNO2 at 80° gives 2,4-dimethyl-3-hydroxy-5-(hydroxymethyl)pyridine (4-desoxyadermine), isolated as the HCl salt, m. 257°.
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Reference:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia