Heyanhao Zhang, Jintao He, Rongqian Cheng, Huanren Yan, Mei-Lin Tang and Jun Chang*,
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引用次数: 0
Abstract
Oligomeric proanthocyanidins (OPCs) have a variety of biological functions, but the formation of 4,8-interflavan bonds faces scaling-up difficulties due to the challenging control of stereoselectivity and the degree of polymerization. Here we report a process to produce procyanidin B3 (1) by mainly optimizing the condensation reaction and improving benzylation, C4 activation, and one-pot hydrogenolysis reactions. In an optimized seven-step process, the product 1 was achieved by only one-step chromatography in the case of poor crystallinity of polyphenols. This strategy provided effective access to the stereoselective synthesis of the title compound and other C4–C8 connected OPCs.
期刊介绍:
The journal Organic Process Research & Development serves as a communication tool between industrial chemists and chemists working in universities and research institutes. As such, it reports original work from the broad field of industrial process chemistry but also presents academic results that are relevant, or potentially relevant, to industrial applications. Process chemistry is the science that enables the safe, environmentally benign and ultimately economical manufacturing of organic compounds that are required in larger amounts to help address the needs of society. Consequently, the Journal encompasses every aspect of organic chemistry, including all aspects of catalysis, synthetic methodology development and synthetic strategy exploration, but also includes aspects from analytical and solid-state chemistry and chemical engineering, such as work-up tools,process safety, or flow-chemistry. The goal of development and optimization of chemical reactions and processes is their transfer to a larger scale; original work describing such studies and the actual implementation on scale is highly relevant to the journal. However, studies on new developments from either industry, research institutes or academia that have not yet been demonstrated on scale, but where an industrial utility can be expected and where the study has addressed important prerequisites for a scale-up and has given confidence into the reliability and practicality of the chemistry, also serve the mission of OPR&D as a communication tool between the different contributors to the field.