Protons and Porphyrins

描述（由申请人提供）：本提案的主要重点是质子（H+）在酸和氢键中的化学作用。金属卟啉是一个额外的兴趣。广泛的目标是揭示基本的新化学，为化学和生物系统中的质子和血红蛋白的分子水平理解提供基础。基础化学的知识基础对现代医学的分子基础是重要的。具体目标包括(i)表征质子的连续水合物（H5O2+, H7O3+， H9O4+等，直到Haq+），并了解它们独特和独特的红外光谱特性（ii）测量目前可达到的范围之外的酸强度，以便新认识的碱度抑制现象可以量化，（iii）红外？碱度标度为？碱（芳烃，烯烃，炔烃），（iv）探索新的分叉氢键，(v)碳硼烷酸活化烷烃，（vi）开发强碳硼烷基亲电试剂以分离新指示物。在卟啉研究中，具体目标包括：(i)质疑铁（III）卟啉中量子力学混合S = 3/2,5/2自旋态的长期接受概念；（ii）研究磁化学系列中的场强与铁（III）卟啉中轴向配体的结合强度之间是否存在关系。本研究计划利用碳硼烷阴离子作为弱配位阴离子和作为碳硼烷酸的超弱共轭碱的特殊性质。这些研究的重点是通过x射线晶体学和各种光谱方法，特别是核磁共振和红外光谱，对纯材料进行明确的表征。公共卫生相关性：质子的研究是基础化学的核心，而基础化学又是现代生物医学科学的隐藏引擎。基础化学为了解疾病控制的分子水平提供了基础，因此对公共卫生至关重要。除了扩大知识基础，美国国立卫生研究院资助的基础化学是培养下一代科学家解决化学基础科学问题的极其重要和特别肥沃的土壤，鼓励他们中最优秀的人从事化学和生物医学科学的职业。

DESCRIPTION (provided by applicant): The main focus of this proposal is the chemistry of the proton (H+), in acids and hydrogen bonding. Metalloporphyrins are an additional interest. The broad objective is to uncover fundamental new chemistry that provides a basis for the molecular level understanding of protons and hemoproteins in chemical and biological systems. A knowledge base of fundamental chemistry is important to the molecular underpinnings of the modern medicine. Specific aims include (i) the characterization of successive hydrates of the proton (H5O2+, H7O3+, H9O4+ etc. up to Haq+) and understanding their distinctive and peculiar IR spectral properties (ii) the measurement of acid strength outside presently accessible ranges so that the newly recognized phenomenon of basicity suppression can be quantified, (iii) the development of an infrared ?NH basicity scale for ? bases (arenes, alkenes, alkynes), (iv) the exploration of new bifurcated H-bonds, (v) the activation of alkanes with carborane acids, and (vi) the exploitation of strong, carborane-based electrophiles to isolate novel dications. In porphyrin research, specific aims include (i) questioning the long-accepted concept of quantum mechanically admixed S = 3/2,5/2 spin states in iron(III) porphyrins and (ii) investigating whether there is a relationship between field strength in the Magnetochemical Series and the binding strength of axial ligands in iron(III) porphyrins. The research plan exploits the special properties of carborane anions as weakly coordinating anions and as superweak conjugate bases of carborane acids. Emphasis in these studies is placed on the definitive characterization of pure materials by X-ray crystallography and a variety of spectroscopic methods, particularly NMR and IR spectroscopies. PUBLIC HEALTH RELEVANCE: The study of the proton is central to fundamental chemistry which, in turn, is the hidden engine of modern biomedical science. Fundamental chemistry gives foundation to the molecular level understanding of disease control and thus, is critical to public health. As well as expanding the knowledge base, NIH-funded fundamental chemistry is a critically important and exceptionally fertile ground for training the next generation of scientists in problem solving in the chemically-based sciences, encouraging the best of them to pursue careers in chemistry and biomedical science.