中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
2,6-二甲氧基-1,4-苯醌 | 2,6-dimethoxy-p-quinone | 26547-64-8 | C8H8O4 | 168.149 |
The structures of seven di- or tetrasubstituted p-benzoquinone derivatives O=C(XC=CH )2C=O and O=C(XC=CX)2C=O with substituents X = -OCH3, -N(CH2)5, - N(CH2CH2)2O, -Cl, -CN and -⊕N(HC=CH)2C-N(CH3)2 are presented and discussed in comparison with published ones substituted by X = -Si(CH3)3, -C6H5, -N(CH3)2, -⊕N(HC=CH)2CN(CH3)2, -O⊖ , and - NO2. Based on the introduction, in which halfwave-reduction potentials, geometry-optimized quantum-chemical calculations on substituent perturbation and known structural data of p-benzoquinone derivatives are used to characterize their molecular ground states. The structural changes indicate how substituent perturbations might be rationalized. Of the categories defined - imperturbed, donor, donor/acceptor and acceptor perturbed - the donorsubstituted p-benzoquinones do exhibit the largest differences, often called cyanine distorsion. In very satisfactory agreement with extensive semiempirical calculations, all effects determined experimentally are discussed in terms of varying charge distribution. With respect to the biochemical importance of p-benzoquinone derivatives, this first structural summary points out important facets.
本文介绍并讨论了七种二取代或四取代的对苯醌衍生物O=C(XC=CH)2C=O和O=C(XC=CX)2C=O的结构,其中取代基X = -OCH3,-N(CH2)5,-N(CH2CH2)2O,-Cl,-CN和-⊕N(HC=CH)2C-N(CH3)2,并与已发表的取代基为X = -Si(CH3)3,-C6H5,-N(CH3)2,-⊕N(HC=CH)2CN(CH3)2,-O⊖和-NO2的结构进行比较。根据介绍,利用半波还原电位、几何优化的量子化学计算对取代基扰动以及已知的对苯醌衍生物的结构数据来表征它们的分子基态。结构变化表明了取代基扰动可能如何被合理解释。在定义的类别中 - 未受扰动、给体、给体/受体和受体扰动中 - 给体取代的对苯醌通常表现出最大的差异,通常被称为靛蓝畸变。与广泛的半经验计算非常一致,实验确定的所有效应都根据不同的电荷分布进行讨论。关于对生物化学重要性的对苯醌衍生物,这个首次的结构摘要指出了重要的方面。