New Catalytic Asymmetric Methods to Control Axial Chirality in Allenes

圣安东尼奥德克萨斯大学的Frantz教授获得了化学系化学催化项目的奖项，他正在开发新的化学反应，以满足未被满足的合成需求，这些需求广泛影响着制药、农产品和先进材料等领域小分子的高效制造。作为该研究计划的一部分，Frantz教授为培养不同层次的学生发展不对称催化和有机合成的现代方法提供了极好的机会。在这项研究的发展过程中获得的技术和知识将提高学生在工业和学术生涯中的竞争优势。此外，人数不足的少数民族和群体、西班牙裔和妇女的征聘和参与是所支助项目的一个关键组成部分。本项目的重点是发现和开发新的催化方法，从可持续的原料合成手性烯。在拟议的资助期内，各种金属基催化剂与手性磷基配体结合，正在评估它们促进中间阳离子乙烯基Pd（II）配合物对映选择性消除β -氢化物的能力，以有效控制烯的轴向手性。具体的探索集中在几种转化上，以探索这种新的化学反应，包括乙烯基硼烷的串联金属化/氢化消除和炔的分子内串联碳金属化/氢化消除。这些转化的一个关键特征是利用了反应歧管，这种反应歧管在大多数金属催化过程中通常被视为非生产性副反应（β -氢化物消除），以实现不对称催化和合成的新生产途径。

With this Award from the Chemical Catalysis Program in the Division of Chemistry, Professor Frantz at the University of Texas at San Antonio is developing new chemical reactions to meet unmet synthetic needs that broadly impact the efficient manufacture of small molecules in areas such as pharmaceuticals, agricultural products, and advanced materials. As a part of this proposed research program, Professor Frantz has developed excellent opportunities to train students at all levels in the development of modern methodologies in asymmetric catalysis and organic synthesis. The techniques and knowledge gained during the development of this research will improve students' competitive edge in both industrial and academic careers. In addition, recruitment and participation by underrepresented minorities and groups, Hispanics and women, is a key component of the supported project.This project focuses on the discovery and development of new catalytic methods to synthesize chiral allenes from sustainable raw materials. In the proposed funding period, various metal-based catalysts in combination with chiral phosphorous-based ligands are being evaluated for their ability to promote an enantioselective beta-hydride elimination from intermediate cationic vinyl Pd(II)-complexes to efficiently control the axial chirality in allenes. Specific explorations focus on several transformations to explore this new chemistry including tandem transmetalation/beta-hydride elimination of vinyl boranes and intramolecular tandem carbometallations/beta-hydride eliminations of alkynes. A key feature of these transformations is the exploitation of a reaction manifold that is typically viewed as an unproductive side-reaction (beta-hydride eliminations) in most metal-catalyzed processes to a new productive avenue in asymmetric catalysis and synthesis.