CAS: New Advances in Sustainable Catalysis

在化学系化学催化项目的支持下，加州大学圣巴巴拉分校的布鲁斯·利普舒茨教授正在研究几种方法，以独家使用水作为反应溶剂，而不是常见的产生废物的有机溶剂。使这一转变成为自然用于化学反应的水的关键技术是基于水溶液中纳米颗粒(NP)的形成。NPs的设计目的是浓缩试剂和催化剂，从而使通常仅在水中无法发生的反应得以发生。此外，考虑到每个NP内反应物和催化剂的浓度很高，将不再需要高温，从而降低了适用于该系统的工艺的能源成本。这些新的进展预计将有助于推动有机化学必须做出的转变，以避免对石油的依赖，许多通常使用的有机溶剂都是从石油中衍生出来的。为了进一步帮助这一向更多以水为基础的学科的过渡，将创建一本手册，其中包含所有在室温下在水中进行的实验，供世界各地的二年级有机实验室使用。其目的将是在非常早期的阶段向学生介绍水中的化学。根据化学系化学催化项目的这一奖项，加州大学圣巴巴拉分校的布鲁斯·利普舒茨教授和他的团队将致力于三个主要研究方向：(1)化学酶催化方面的创新，其中阻碍该领域发展的兼容性问题涉及在单个反应容器中的水中同时使用化学催化和酶过程，已通过在缓冲的水介质中添加少量表面活性剂来简化和促进；(2)选择的硫代酯的原位生成，然后与原位生成的有机锌试剂反应，从而导致在一锅和在水中生成不对称酮的新途径；以及(3)基于纳米胶束阵列中存在的非典型情况，在有机化学中发展了一个新的概念，即，作为提高对映体选择性(ee‘s)的手段，高浓度和有限的反应物和催化剂的迁移率，而不是传统的在低温下使用有机溶剂。如果这一发现被证明是普遍的；可以通过利用水胶束介质最大化ee，潜在地减少对昂贵的低温反应条件的依赖来达到和保持低温，这将是对催化的重要补充，也将是在推进水中的化学方面向前迈出的重要一步。PI和他的团队致力于精细化工行业，特别是制药行业，以将这些进步应用于实际。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Chemical Catalysis program in the Division of Chemistry, Professor Bruce Lipshutz of the University of California at Santa Barbara is studying several approaches to the exclusive use of water as a reaction solvent, rather than the common, waste-generating organic solvents. The key technology enabling this switch to water, which Nature uses for chemical reactions, is based on the formation of nanoparticles (NPs) in the aqueous solutions. The NPs are designed to concentrate reagents and catalysts, thus enabling reactions to occur that would normally fail in water alone. Moreover, given the high concentrations of reactants and catalyst within each NP, high temperatures needed will no longer be required, reducing energetic cost of processes amenable to this system. These new advances are expected to contribute to the shift that organic chemistry, in general, must make to avoid its dependence on petroleum, from which derive many of the organic solvents typically used. To further assist with this transition to a more aqueous-based discipline, a Manual will be created containing experiments, all to be done in water at room temperature, for use in sophomore organic laboratories worldwide. The intention will be to introduce students at a very early stage to chemistry in water. Under this award from the Chemical Catalysis program in the Division of Chemistry, Professor Bruce Lipshutz of the University of California at Santa Barbara and his team will pursue three main research directions: (1) innovations in chemoenzymatic catalysis, where the compatibility problem that has prevented the advancement of this field involving both chemocatalytic and enzymatic processes to be used in water in a single reaction vessel has been streamlined and facilitated by adding small amounts of a surfactant in the buffered aqueous medium; (2) the in situ-formation of selected thio-esters that are then subject to reaction with in situ-generated organozinc reagents, thereby leading to a new route to unsymmetrical ketones, in one pot and in water; and (3) development of a new concept in organic chemistry based on the atypical situation that exists within nano-micellar arrays; that is, high concentrations and limited reactant and catalyst mobility as a means of enhancing enantioselectivities (ee’s), rather than the traditional use of organic solvents at low temperature. Should this discovery prove to be general; that ee’s can be maximized by utilization of aqueous micellar media, potentially reducing dependence upon costly cryogenic reaction conditions to achieve and maintain low temperatures, this will be both an important addition to catalysis and a major step forward in advancing chemistry in water. The PI and his group are engaged with the fine chemical industry, in particular the pharmaceutical industry, so as to bring these advances to practical application.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.