Presidential Young Investigator Award/Development of New Organometallic Reagents (Chemistry)

霍金斯博士是总统年轻的新调查员 有机和高分子研究者奖 化学课程。 在此基础上，我们将研究 使用有机金属试剂的新的有机合成方法。 这将提高我们有效地合成 用于现代医学和农业的复杂分子。 对于第一个项目，金属羰基化合物将被处理， 含有相容的亲核和 亲电位点 将亲核部分加成到 配位的一氧化碳的碳应该产生 金属亲核试剂靠近现在悬垂的亲电试剂 部分。 将得到的复合物进行环化 到金属乳糖，然后可以减少消除 所需的选择性羰基化有机产物。 环氧 醇、环氧胺和锍叶立德将被检查 作为双功能有机基质。 预期 与环氧化物的反应对应于羟醛合成子，其中 起始环氧化物的几何形状控制产物的相对分子质量， 立体化学 环氧胺可相应地给出 具有立体化学控制的β-内酰胺 底物可以提供一种新的途径过渡金属烯酮 配合物 第二个项目将涉及综合， 手性二卤代硼烷的拆分和应用 π碱基 一种同时具有刘易斯碱性和 π-酸性位点如α，β-不饱和酯应 通过同时协同的刘易斯作用与这些催化剂结合 酸-碱和π-酸-碱相互作用。 的约束 这种两点绑定所施加的可能会导致 选择性地封端烯烃。 因此，另一面 会对试剂开放 将对二烯进行检测 在这里;位移的协调π基地由一个传入 二烯可导致不对称Diels桤木反应。 没有 更长时间地包含用于第二结合点的π-酸， 环己烯产物应该通过以下方式从催化剂中置换出来 两点结合起始材料。 催化剂 为了优化这种酶样结构， 场景 用于立体定向邻位的方法 双键的双甲基化将在第三个 项目 烯属底物与 杂环双-μ-亚甲基复合物可导致插入 其中一个金属-碳键， 1，3-二金属环己烷。 这个物种可以还原 除去金属杂环戊烷，其可被质子化， 所需的双甲基化产物。 Mo-Co和Mo-Fe配合物 将在这方面进行研究。

Dr. Hawkins is a new investigator under the Presidential Young Investigator Award from the Organic and Macromolecular Chemistry Program. Under this will be studied the development of new organic synthetic methods using organometallic reagents. These will increase our capacity to synthesize efficiently the complex molecules used in modern medicine and agriculture. For the first project, metal carbonyls will be treated with organic substrates containing compatible nucleophilic and electrophilic sites. Addition of the nucleophilic moiety to the carbon of coordinated carbon monoxide should generate a metal nucleophile in proximity to the now pendant electrophilic moiety. The resulting complex will be set up for cyclization to a metallacycle, which may then reductively eliminate the desired selectively carbonylated organic product. Epoxy alcohols, epoxy amines, and sulphonium ylides will be examined as the bifunctional organic substrates. The anticipated reaction with epoxides corresponds to an aldol synthon where the starting epoxide's geometry controls the product's relative stereochemistry. Epoxy amines may accordingly give beta-lactams with stereochemical control The sulphonium ylide substrates may provide a new route to transition metal ketene complexes. The second project will involve the synthesis, resolution, and application of chiral dihaloboranes containing pi-bases. A substrate possessing both Lewis basic and pi-acidic sites such as an alpha, beta-unsaturated ester should bind to these catalysts via simulataneous synergistic Lewis acid-base and pi-acid base interactions. The constraints imposed by this two-point binding may cause one face of the olefin to be selectively blocked. Accordingly, the other face will be open to approach by reagents. Dienes will be tested here; displacement of the corrdinated pi-base by an incoming diene may result in an asymmetric Diels Alder reaction. No longer containing a pi-acid for a second binding point, the cyclohexene product should be displaced from the catalyst by the two-point binding starting material. The catalyst structures will be varied in order to optimize this enzyme-like scenario. Methods for the stereospecific vicinal bismethylation of a double bond will be explored in a third project. Coordination of an olefinic substrate to a heterobimetallic bis-mu-methylene complex may lead to insertion into one of the metal-carbon bonds forming a 1,3-dimetallacyclohexane. This species may then reductively eliminate a metallacyclopentane which can be protonolyzed to the desired bismethylated product. Mo-Co and Mo-Fe complexes will be studied in this vein.