Microwave-Assisted Protocols Applied to the Synthesis of 1′,2,3,3′,4,4′-Hexa-O-benzylsucrose

Abstract

The sucrose derivative 1′,2,3,3′,4,4′-hexa-O-benzylsucrose is a key intermediate for the chemoselective synthesis of various useful materials, such as macrocycles, crown ether analogs, and polymers. Several strategies for the synthesis of this compound were explored by applying microwave-assisted protocols, thus permitting significant reductions of time and energy compared to other routes. The outcomes of the different approaches were compared and the optimal one, in terms of yield and reproducibility, was found to be the initial protection at the positions 6 and 6′, with tert-butyldiphenylsilylchloride (TBDPSCl) in the presence of 4-(dimethylamino)pyridine (4-DMAP) and pyridine as a solvent, then perbenzylation of the remaining hydroxyl groups, followed by selective deprotection of the TBDPS groups to obtain the title compound.

GRAPHICAL ABSTRACT

Keywords:

• Carbohydrates
• chemoselective synthesis
• microwave chemistry
• protection–deprotection strategies
• sucrose derivatives

ACKNOWLEDGMENTS

The NMR spectra were obtained using spectrometers that are part of the National NMR Facility, supported by Fundação para a Ciência e a Tecnologia (RECI/BBB-BQB/0230/2012). MALDI-TOF spectra were acquired by the Laboratório de Análises/REQUIMTE at the Departamento de Química of Universidade Nova de Lisboa.