Palladium-Catalyzed Aryldiazonium Salts Mediated Stereocontrolled Synthesis of 2-Deoxy Aryl-C-Glycosides from Glycals

S2.1 Oligosaccharide synthesis I
Location (hall): 
Start/end time: 
Monday, July 1, 2019 - 15:15 to 15:20

Jeyakumar Kandasamy1

1Indian Institute of Technology (BHU)-Varanasi, Varanasi, India

Aryl C-glycoside is one of the distinct motifs found in various bio-active molecules and natural products [1]. In this context, synthesis of 2-deoxy aryl-C-glycosides has attracted tremendous interest in carbohydrate Synthesis [2]. Most of the previous reports suffer from different disadvantages including use of harsh and dry reaction conditions, poor yield, longer reaction time, etc. In this context, here we disclose the synthesis of 2-deoxy aryl-C-glycosides from different glycals and aryldiazonium salts in the presence of palladium acetate at room temperature (Figure 1). A wide range of glycals including D-glucal, D-galactal, L-rhamanal, D-xylal and D-ribal underwent coupling with aryldiazonium salts and gave synthetically useful 2,3-deoxy 3-keto α(or) β-aryl-C-glycosides selectively in good to excellent yields [3]. This method does not require any external oxidant, base or ligand.

Figure 1. Synthesis of aryl glycosides from glycals and aryldiazonium salts

  1. a) Yang, Y.; Yu, B. Chem. Rev. 2017, 117, 12281−12356. b) Kitamura, K.; Ando, Y.; Matsumoto, T.; Suzuki, K.; Chem. Rev. 2018, 118, 1495−1598.  
  2. a) Liu, C. F.; Xiong, D. C.; Ye, X. S. J. Org. Chem., 2014, 79 , 4676-4686; b) Steinhuebel, D. P.;  Fleming, J. J.; Du Bois, J.  Org. Lett., 2002, 4, 293-295. c) Li, H. H.; X. S. Ye, Org. Biomol. Chem., 2009, 7, 3855-3861.
  3. A .K. Singh, J. Kandasamy, Org. Biomol. Chem., 2018,16, 5107-5112.