5-Substituted 4,5-Dihydro-1,2,4-triazin-3(2H)-ones from the Unprecedented Reaction between α-N-Protected Amino Acid Hydrazides and NaBH4
作者:Giancarlo Verardo、Paola Geatti、Marcello Merli、Paolo Strazzolini
DOI:10.1002/ejoc.200500989
日期:2006.6
α-N-Protected amino acid hydrazides (1) readily reacted with NaBH4 to afford 5-substituted 4,5-dihydro-1,2,4-triazin-3(2H)-one derivatives 2 in good yields. Unfortunately, the reaction caused partial racemization at the α-amino acidic carbon atom of the starting hydrazide. A mechanism, supported by experimental evidence, has been proposed in an attempt to explain this to date unprecedented reaction. The structure
α-N-保护的氨基酸酰肼 (1) 很容易与 NaBH4 反应,以良好的产率得到 5-取代的 4,5-二氢-1,2,4-triazin-3(2H)-one 衍生物 2。不幸的是,该反应导致起始酰肼的 α-氨基酸碳原子部分外消旋化。已经提出了一种由实验证据支持的机制,试图解释这种迄今为止前所未有的反应。化合物2的结构经X射线结构分析证实。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)