Controlled Release of Perfumery Alcohols by Neighboring-Group Participation. Comparison of the Rate Constants for the Alkaline Hydrolysis of 2-Acyl-, 2-(Hydroxymethyl)-, and 2-Carbamoylbenzoates
作者:Jean-Yves de Saint Laumer、Eric Frérot、Andreas Herrmann
DOI:10.1002/hlca.200390236
日期:2003.8
2-[(ethylamino)carbonyl]benzoates were found to have the highest rate constants for the alkaline ester hydrolysis, followed by unsubstituted 2-(aminocarbonyl)benzoates, or the corresponding isopropyl derivatives. To rationalize the influence of the different structural changes on the hydrolysis kinetics, the experimental data obtained for the 2-[(alkylamino)carbonyl]benzoates were compared with the
一系列的2- acylbenzoates 1和2,2-(羟甲基)苯甲酸酯3,2-carbamoylbenzoates 4 - 6,以及氨基甲酰酯7或8分别的马来酸盐或琥珀酸盐,(参见图2),在制备几个反应步骤,并研究了这些化合物作为伯,仲和叔香料醇的受控释放的化学传递系统的潜在用途。通过肛门确定邻基团辅助的碱性酯水解的速率常数。在不同pH的H 2 O / MeCN缓冲溶液中进行HPLC (表1)。发现水解速率取决于醇的结构,前体骨架以及攻击酯功能的相邻亲核试剂的结构。伯醇的释放速度比仲醇和叔醇要快,而烯丙基伯醇(例如香叶醇)的苯甲酸酯的水解速度比同源饱和醇(如香茅醇)快2-4倍。对于相同的离去醇,环2-[((乙基氨基)羰基]苯甲酸酯的环化速度比相应的2-(羟甲基)苯甲酸酯快,并且环化的速度比其2-甲酰基和2-乙酰基类似物快(例如,参见图4。)。在氨基甲酸酯系列中,发现2-[((乙基氨基)羰