Synthesis of Tetraoxygenated Terephthalates via a Dichloroquinone Route: Characterization of Cross-Conjugated<i>Liebermann</i>Betaine Intermediates
作者:Lukas Hintermann、Philipp J. Altmann、Panče Naumov、Keisuke Suzuki
DOI:10.1002/hlca.201600392
日期:2017.4
Cross‐conjugated quinoid betaines 4 (2,5‐bis(alkoxycarbonyl)‐3,6‐dioxo‐4‐(1‐pyridinium‐1‐yl)cyclohexa‐1,4‐dien‐1‐olates; Liebermann betaines) were synthesized from 2,5‐dichloro‐3,6‐dioxocyclohexa‐1,4‐diene‐1,4‐dicarboxylates (2) and pyridines in acetone containing H2O. Their structure was secured by NMR spectroscopy and by X‐ray diffraction analysis of 4f (alkoxy = EtO, pyridine = 4‐Me2N–C5H4N). Betaines 4 show comparatively
合成了交叉共轭醌类甜菜碱4(2,5-双(烷氧基羰基)-3,6-二氧代-4-(1-吡啶鎓-1-基)环己基1,4-二烯-1-油酸酯;利伯曼甜菜碱)由含H 2 O的丙酮中的2,5-二氯-3,6-二氧代环己-1,4-二烯-1,4-二羧酸盐(2)和吡啶组成。其结构通过NMR光谱法和X射线衍射分析确定的4F(烷氧基=环氧乙烷,吡啶= 4-ME 2 N-C 5 H ^ 4 N)。甜菜碱4由于具有交叉共轭特性,因此对亲核试剂具有较高的反应性。甜菜碱4a和羟基-3,4-亚甲二氧基苯(芝麻酚)缩合生成吡啶鎓盐喹啉14,其具有从一个吡啶鎓N A分叉氢键+ -H施主到两个羰基(C = O)和酚盐(C-O - )固态的受体。甜菜碱4b在水溶液中水解得到吡啶鎓盐或吡啶鎓盐的聚合锌(II)络合物的二乙基2,5-二羟基-3,6-二氧代环己-1,4-二烯-1,4-二羧酸盐(11)ZnCl 2存在下的11阴离子。通过分析将二羟基醌11与独立制备的对苯二酚2