Practical Aqueous Reactions Leading To Skeletally Diverse Carbohydrate-derived Ketones

Carbohydrates are the most abundant renewable organic compounds on earth and the quantities produced exceed those for other renewable organic compounds. Therefore utilizing carbohydrates for chemical, energy and material supplies to replace fossil fuels is an important area for sustainable development.In this paper, we have developed methods to synthesize skeletally diverse carbohydrate-derived ketones starting from partially protected carbohydrates and methyl ketones in one pot. Those reactions catalyzed by cheap catalysts(LiOH, FeCl3 and HCl) and most of the reaction media were water. The reaction conditions were mild and most of the reactions were carried out at 60 oC or at room temperature. Further, all the reaction yields were good to excellence. We got 37 carbohydrate-derived ketones with four diverse types: furan-substituted diketones, furan-substituted ?,?-unsaturated ketones, enetriketones and dienediketones. Each of the four types of ketones has been scaled up to using 10 g of O-benzyl-protected D-glucosyl or D-xylosyl hemiacetals. Two types of carbohydrate-derived ketones contain C=C, C=O and OH groups and are not accessible via currently known methods.In conclusion, four types of skeletally diverse compounds have been synthesized from protected aldosyl hemiacetals and methyl ketones using cheap catalysts in water in one pot. The reactions are operationally simple, high yielding and scalable, which opens a practical channel for utilizing carbohydrates to produce chemical and pharmaceutical intermediates and products.