中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | 3-methyl-2,6-di-t-butylpyrimidin-4(3H)-one | 122980-64-7 | C13H22N2O | 222.33 |
2,4,6-三叔丁基嘧啶 | 2,4,6-tri-tert-butylpyrimidine | 67490-21-5 | C16H28N2 | 248.412 |
—— | 2,4-di-tert-butyl-6-chloropyrimidine | 69050-89-1 | C12H19ClN2 | 226.749 |
—— | 4-bromo-2,6-di-tert-butyl-pyrimidine | 69543-99-3 | C12H19BrN2 | 271.2 |
t-Butyllithium and t- butylmagnesium chloride cyanocuprates were used to prepare 4(6)-t- butylpyrimidines from the corresponding 4(6)-halopyrimidines . The highly hindered 2,4,5-tri-t-butyl-6-chloropyrimidine, containing an ortho-di-t-butyl arrangement, was prepared by this method. No alkyl group isomerization was observed but some substrate reduction was detected.
Anions derived from t-butyl-substituted pyrimidin-4-ols were methylated with iodomethane . The site of methylation was determined by proton-coupled 13C n.m.r. and the relative proportions of isomers were determined by 1H n.m.r. A t-butyl substituent ortho to a ring nitrogen markedly reduced the propensity for methylation at that nitrogen to the point where O-methylation, uncommon under these conditions, was observed.