A New and More Efficient Synthesis of Methylene Acetals

Chu, Guobiao; Zhang, Yanqiao; Li, Chunbao; Zhang, Yuqing

doi:10.1055/s-0029-1216992

Cited by 2 publications

(1 citation statement)

References 5 publications

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“…Crystalline β-glycosyl benzoate 1a , which can be prepared quantitatively according to our recently published method, was selected as the carbohydrate donor, and lauryl alcohol ( 2a ) was selected as the acceptor (Table ). Cyanuric chloride-activated dimethyl sulfoxide (DMSO) has been investigated as a precatalyst in several synthetic methods, − and it has been shown to have Lewis acid properties. Therefore, cyanuric chloride and DMSO were used to promote the glycosylation between 1a and 2a in acetonitrile (MeCN) at 80 °C.…”

Section: Results and Discussionmentioning

confidence: 99%

Practical Glucosylations and Mannosylations Using Anomeric Benzoyloxy as a Leaving Group Activated by Sulfonium Ion

Xing

Niu

2017

ACS Omega

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One obstacle for practical glycosylations is the high cost of promoters and low-temperature equipment. This problem has been at least partially solved by using MeSCH2Cl/KI as a low-cost promoter system. MeSCH2Cl has an estimated cost of <$1/mol compared with $1741/mol for AgOTf and $633/mol for TMSOTf. This new promoter system is capable of activating various leaving groups including anomeric Cl, F, trichloroacetimidate, and acyloxy groups. Stable and easy-to-prepare anomeric benzoloxy carbohydrate donors were investigated in the glycosylations of carbohydrates, aliphatic alcohols, amino acids, steroids, and nucleoside acceptors. Most of these glycosylations were operationally simple with fast reaction rates and moderate yields of 35–79%. In addition, direct glycosylations of nucleosides using less than 2 equiv of anomeric benzoloxy donors and high stereoselective mannosylation have been achieved. From an economic point of view, this glycosylation method should be highly applicable to industrial processes.

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