Sulfonation and sulfation of 1,3-dihydroxybenzene and its methyl ethers in concentrated sulfuric acid
作者:Hans Cerfontain、Ankie Koeberg-Telder
DOI:10.1002/recl.19881070905
日期:——
homogeneous sulfonations of 1,3-dihydroxybenzene (1), its monomethyl (2) and dimethyl ether (3) in concentrated aqueous sulfuric acid at 25°C have been studied and isomer distributions and rate coefficients for the sulfonation of 1–3 and their monosulfonic acids are reported. The initial process, upon dissolution of the reactants, is protonation at C(4) and C(6). The subsequent sulfonation of the symmetrical
研究了1,3-二羟基苯(1),其单甲基(2)和二甲醚(3)在25°C浓硫酸中的均相磺化反应,以及异构体分布和磺化1〜3和2的速率系数。报道了它们的单磺酸。反应物溶解后的初始过程是在C(4)和C(6)质子化。随后对称反应物1和3的磺化反应生成4-磺酸,而2和2的4-和6磺酸在73.5%H 2 SO 4下的比率为0.8 + 0.1 。1的4-磺酸的磺化(1 -4-S)产生2,4-和4,6-二磺酸的混合物,2 -4-S和3 -4-S产生4,6-S 2和2-6 -S给出2,6-和4,6-S 2的混合物。二磺酸1 -2,4-S 2和2 -2,6-S 2均缓慢异构化,得到4,6-二磺酸异构体。在酸浓度≥82.8%H 2 SO 4时,1的二磺酸缓慢生成1 -2,4,6-S 3,而2和3的二磺酸则缓慢生成1 -2,4,6-S 3。不进一步磺化。不存在的2 -2,4-S 2从2 -4-S和2 -2,4,6--S