Basicity Enhancement by Multiple Intramolecular Hydrogen Bonding in Organic Superbase N , N ′, N ″, N ‴-Tetrakis(3-(dimethylamino)propyl)triaminophosphazene

作者：Sebastian Ullrich, Danijela Barić, Xiulan Xie, Borislav Kovačević, Jörg Sundermeyer · 发表于：Organic Letters · 年份：2019 · DOI：10.1021/acs.orglett.9b03521 · 被引用次数：15 · 研究领域：Chemical Reaction Mechanisms、Organophosphorus compounds synthesis、Structural and Chemical Analysis of Organic and Inorganic Compounds

With the synthesis of N, N ′, N ″, N ‴-tetrakis(3-(dimethylamino)propyl)triaminophosphazene ( TDMPP, 1 ), we present the first phosphazene superbase with enhanced basicity through the effect of multiple intramolecular hydrogen bonding (IHB). Due to intramolecular solvation of four NH protons, the proton affinity is even higher than that of second-order phosphazene (dma)P 2 - t Bu. X-ray structural proof, NMR titration experiments, and computational investigations provide a more detailed quantitative description of the IHB influence on the superbasicity of 1 in solid-state, solution, and the gas-phase.