The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Degradation of Cyclohexane to Benzene》. Authors are Willstatter, Richard; Hatt, Daniel.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).Application In Synthesis 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., 6, 748.-The prepare of cyclohexene by heating cyclohexanol with (CO2H)2 (Zelinskii and Zelikov, Ber., 34, 3251) gives poor yields owing to the formation (15 g. from 60 g. of alc.) of dicyclohexyl oxalate, (CO2 C6H11)2, quadratic leaves, m. 42°. Brunel’s method (use of KHSO4, Bull. soc. chim. 33, 270) gives an 80% yield, together with (C6H11)2O, b. 97-8.5°,b737 259-40° (Ipatiev and Philipov, C. A., 3, 1014, give the b. p. as 275-7°). Cyclohexene dibromide, heated 9 hrs. at 110-5° in scaled tubes with 6 mols. NHMe2 in 18% C6H6 solution, gave 75% of δ-dimethylaminocyclohexene, b725 89-91.5°, b725 160.5-2.5°. Chloroplatinate, prisms, m. 185°. Methiodide, needles, m. 173-4° 1,3-Cyclohexadiene prepared by Crossley’s method from cyclohexene dibromide and quinoline (J.Chem.Soc., 85, 1403) contains cyclohexene, bromocyclohexene and C6H6 (20% of the latter in 145 g. of the crude product). Obtained pure by Harries’ method (C. A., 6, 108), It b72, 78.3-8.8°, d420 0.8404, nD20 1.47439,nα20 1.47025,nβ20 1.48516, nγ20 1.49491, MD 26.77, Mα 26.59, Mβ 27.19, Mγ 27.55, Mγ-α 0.97. It quickly absorbs 4 ats.H in the presence of Pt. With NHMe2 in cold concentrateC6H6 solution, the dibromide gives quant. Δ2-tetramethyldiaminocyclohexene, b10 90.5-2.5°, b725 219.5-3-5°, d40 0.920. Chloroplatinate, rhombic tablets, blacken 240°, decompose 259-60°. Methiodide, microscopic quadratic tables, m. 236° (decompose); the quaternary base obtained by the action of Ag2O on the methiodide, decompose, on evaporation of the solution, into C6H6 and NMe2, the temperature of decompose depending on the pressure (98-104° at atm. pressure with an 80-5% yield of C6H4; 40-50° under 20° mm.; -3° to 5° under 0.008-0.02 mm.
Compounds in my other articles are similar to this one(5-(hydroxymethyl)-2,4-dimethylpyridin-3-ol hydrochloride)Application In Synthesis of 5-(hydroxymethyl)-2,4-dimethylpyridin-3-ol hydrochloride, you can compare them to see their pros and cons in some ways,such as convenient, effective and so on.
Reference:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia