3, 4-Di-O-acetyl-L-rhamnal is a useful synthetic intermediate in synthesis of biologically active naturalproducts and polysaccharide. Also, it can be serviced as glycosyl donors to synthesize O-glycosides,C-glycosides,S-glycosides, N-glycosidesand cyclopropanated carbohydrates. Moreover, 3, 4-Di-O-acetyl-L-rhamnal is also a versatile synthon which can be used in a wide range of addition, rearrangement andsubstitution reactions.

Over the past several decades, numerous synthetic methods of glycals have been developed, but majority of these traditional methods are suffering from several drawbacks including the use of very expensive and toxic reagents, intricate laboratory operations, complex multi-step processes and accomplished with low yield. Therefore, it is very necessary to develop a simple, mild, less toxic, economical, environmentally benign and user-friendly reaction protocol for their preparations.

Prof. Shao Huawu and coworkers from Chengdu Institute of Biology, Chinese Academy of Sciences, recently reported a new method to synthesize 3,4-Di-O-acetyl-L-rhamnal, which have been authorized with application invention patents by National Copyright Administration (NCA) in March of 2012.

Thissynthetic process involved in treating 2, 3, 4-Tetra-O-acetyl- L- rhamnosyl bromides with zinc powder and sodium dihydrogen phosphate solution in ethyl acetate or acetone, which can furnish 3, 4-Di-O-acetyl-L-rhamnal in high yield. This method provides several advantages such as high yield, simple work-up procedure, shorter reaction time, milder conditions and environ-mental friendliness.