氢负理论与氧化还原反应

Hydrogen Negative Theory and Redox Reaction

关键词:  氢负理论  氧化还原反应  极性反应  

Key words:  hydrogen negative theory  oxidation-reduction reaction  polar reaction

摘要:

化学制药工艺的研究中,氧化还原反应尚存在诸多含混不清、似是而非的问题。我们通过对硼氢化钠的来源、还原机制和还原能力等现象进行思考,提出“氢负(H_^- )”的概念,进而推广至其它金属还原剂,比如LiAlH₄,Red-Al,DIBAL-H,Et₃SiH,分析指出其还原性皆是因为B、Al、Si与H的电负性差导致氢负的产生。在传统催化氢化的自由基理论基础上提出了另外一种极性反应假说,并对生物催化氧化还原反应中的羰基还原过程进行了详细解释,进一步证实氢负理论的合理性。同时,在氢负还原剂的基础上推导出氧化剂大多是氢氧正(HO_⁺)或活性氧(₊^O_-),揭示了氧化剂的共性特点。还对生物酶催化氧化反应案例剖析,结果显示氧化反应总是与还原反应形影相伴。在氢负理论的指导下,对多种涉及氧化还原的人名反应进行重新解读,修正或提出了更合理的机理假说,初步探讨了催化剂在氧化还原反应中的作用。最后,对氧化还原反应进行了精准定义,把极性反应划分为取代反应和氧化还原反应,揭示了氧化还原的本质特点在于发生“极性颠倒”。

Abstract:

In the research of chemical pharmaceutical processes, there are still many ambiguous and seemingly ambiguous issues regarding redox reactions. We propose the concept of "hydrogen negative (H -)" by considering the sources, reduction mechanisms, and reducing abilities of sodium borohydride, and then extend it to other metal reducing agents such as LiAlH4, Red-Al，DIBAL-H，Et3SiH， The analysis indicates that their reducibility is due to the difference in electronegativity between B, Al, Si, and H, which leads to the generation of hydrogen negativity. On the basis of the free radical theory of traditional catalytic hydrogenation, another polar reaction hypothesis was proposed, and the carbonyl reduction process in biocatalytic oxidation-reduction reactions was explained in detail, further confirming the rationality of the hydrogen negative theory. Meanwhile, based on the hydrogen negative reducing agent, it is deduced that most oxidants are hydrogen oxygen positive (HO+) or reactive oxygen species (+O-), revealing the common characteristics of oxidants. An analysis of cases of enzymatic oxidation reactions was also conducted, and the results showed that oxidation reactions are always accompanied by reduction reactions. Guided by the theory of hydrogen negativity, various reactions involving oxidation-reduction have been reinterpreted, and more reasonable mechanistic hypotheses have been revised or proposed. The role of catalysts in oxidation-reduction reactions has been preliminarily explored. Finally, a precise definition of oxidation-reduction reactions was provided, dividing polarity reactions into substitution reactions and oxidation-reduction reactions, revealing that the essential characteristic of oxidation-reduction is the occurrence of "polarity reversal"