I-Corps: Selectively convert biomass-derived carbohydrates through a thermochemical process

I-Corps项目的更广泛影响/商业潜力在于可持续发展、绿色化学和先进制造领域。生物质衍生的非食物碳水化合物是一种丰富的可再生碳源，但它们很难加工成任何有用的燃料、化学品或材料产品。拟议的活动寻求发展一种新的热方法，将碳水化合物转化为高价值的化学品和化学前体，特别是那些不能轻易从石油或天然气中生产出来的化学品和化学前体。被广泛研究的热解热过程的主要限制是产生的产物太多，无法有效和经济地净化。尽管热解固有的浪费，一种非常理想的化合物，称为无水糖，仍然是通过碳水化合物热解在小规模生产。特别是一种叫做左旋葡聚糖（LGA）的无水糖化合物，它是合成几类天然产物的原料，比如重要的抗寄生虫药物阿维菌素和抗生素。LGA的更大可及性和可负担性将导致最终药物或药物的更大可及性和可负担性。I-Corps项目最初将重点放在左旋葡聚糖（LGA）上，作为演示改进热解技术的测试案例。该技术基于新研究的环锁定概念，即在热解前对糖分子进行化学修饰。当烷氧基或苯氧基附着在葡萄糖环上的特定位置时，葡萄糖生成LGA成为主要反应（1,6消除途径）。取代基抑制葡萄糖环打开和分裂成非无水糖产物（开环途径）。换句话说，糖环经过化学修饰后，开环比1,6消除具有更高的激活势垒。经化学改性的糖热解后，对LGA的选择性由2%提高到90%以上。这种改进的热解技术可以应用于其他糖和复杂碳水化合物。

The broader impact/commercial potential of this I-Corps project lie in the areas of sustainability, green chemistry, and advanced manufacturing. Biomass-derived, non-food-based carbohydrates are an abundant and renewable source of carbon, but they are very difficult to process into any useful fuel, chemical or materials products. The proposed activity seeks the development of a new thermal approach to convert carbohydrates into high-value chemicals and chemical precursors, especially those that cannot be readily produced from petroleum or natural gas. The main limitation of the widely studied thermal process known as pyrolysis is that the generated products are too numerous to purify efficiently and economically. In spite of the wastefulness inherent in pyrolysis, one highly desirable class of compounds called anhydrosugars is still produced through carbohydrate pyrolysis at small scale. In particular, the anhydrosugar compound called levoglucosan, or LGA, is the starting material in the synthesis of several classes of natural products, like the important antiparasitic drug Avermectin and antibiotics. Greater accessibility and affordability of LGA would lead to greater accessibility and affordability of the eventual drug or medication.This I-Corps project initially focuses on levoglucosan (LGA) as the test case for demonstrating the improved pyrolysis technology. This technology is based on the newly researched concept of ring-locking, in which a sugar molecule is chemically modified prior to pyrolysis. LGA formation from glucose becomes the dominant reaction (1,6-elimination pathway) when an alkoxy or phenoxy group is attached to a specific location on the glucose ring. The substituent group inhibits the glucose ring from opening and fragmenting into non-anhydrosugar products (ring-opening pathway). In other words, ring-opening has a much higher activation barrier than 1,6-elimination, after the sugar ring is chemically modified. The selectivity to LGA increases from 2% to greater than 90% after pyrolysis of the chemically modified sugar. This improved pyrolysis technology can be applied to other sugars and complex carbohydrates.