硝基苯基四氢吡喃基乙缩醛(3e; Y = H)的水解,其基团通过反式环连接固定在赤道上,比相应的构象柔性乙缩醛的水解要慢得多。它也比轴向异构体的水解慢,在酸中的水解速度是原来的60倍,但对于自发反应只有2倍。建议(3e)的两个反应都是缓慢的,因为存在赤道离去基团离开的立体电子屏障,在乙缩醛中心的构象被反式固定的系统中不容易克服。-环结。(3a)的自发水解似乎很慢,其原因是不同的:从最初的C–O裂解产物内部快速返回,迫使速率决定步骤改变为氧代碳鎓离子水合,如溶剂氘所示。反应的同位素效应。
Nachbargruppeneffekte bei der aminolyse von estern—I
作者:Volker Böhmer、Klasu Wörsdörfer、Ulrike Becher
DOI:10.1016/0040-4020(78)88412-9
日期:1978.1
The kinetics of the aminolysis of different nitrophenylacetates were investigated with n-butylamine in dioxane at 20°C. The reaction rate can be described up to high concentrations of amine (~1 mole dm−3) by the equation v=k2[ester][amine]+k3[ester][amine]2. The ratio is larger for p-nitrophenylacetates than for o-nitrophenylacetates, while for 2,4-dinitrophenylacetates a third order term is not observed
用正丁胺在20℃的二恶烷中研究了不同硝基苯乙酸酯的氨解动力学。可以通过等式v = k 2 [酯] [胺] + k 3 [酯] [胺] 2来描述反应速率,直至高达高浓度的胺(〜1摩尔dm -3)。对-硝基苯基乙酸酯的比率大于邻-硝基硝基乙酸酯的比率,而对于2,4-二硝基苯基乙酸酯,没有观察到三阶项。
Kinetics of the reaction of chloromethylated phenols with aniline and substituted anilines
作者:Günter Stein、Hermann Kämmerer、Volker Böhmer
DOI:10.1039/p29840001285
日期:——
The kinetics of the reaction of several chloromethylated phenols with substitutedanilines, mainly p-nitroaniline, were studied for dimethyl sulphoxide solution by conductivity measurements. Substitution of the chlorine atoms proceeds in two steps. In a reversible step hydrogen chloride is eliminated by a suitable base to form a quinone methide. The aniline is added to this intermediate in the second
作者:Stein, Guenter、Boehmer, Volker、Lotz, Werner、Kaemmerer, Hermann
DOI:——
日期:——
Stereoelectronic control of the hydrolysis of a conformationally locked acetal
作者:Anthony J. Kirby、Robert J. Martin
DOI:10.1039/p29830001627
日期:——
The hydrolysis of the nitrophenyltetrahydropyranyl acetal (3e; Y = H), with leaving group fixed equatorial by the trans-ring junction, is substantially slower than expected for a comparable conformationally flexible acetal. It is also slower than the hydrolysis of the axial isomer, by a factor of 60 in acid, but only 2 for the spontaneous reaction. It is suggested that both reactions of (3e) are slow
硝基苯基四氢吡喃基乙缩醛(3e; Y = H)的水解,其基团通过反式环连接固定在赤道上,比相应的构象柔性乙缩醛的水解要慢得多。它也比轴向异构体的水解慢,在酸中的水解速度是原来的60倍,但对于自发反应只有2倍。建议(3e)的两个反应都是缓慢的,因为存在赤道离去基团离开的立体电子屏障,在乙缩醛中心的构象被反式固定的系统中不容易克服。-环结。(3a)的自发水解似乎很慢,其原因是不同的:从最初的C–O裂解产物内部快速返回,迫使速率决定步骤改变为氧代碳鎓离子水合,如溶剂氘所示。反应的同位素效应。