Tert-Butyl Nitrite Mediated Palladium Catalysed One-Pot Stereoselective Synthesis of Aryl-C-Glycosides from Glycals and Anilines

PS2 Poster session 2 Even numbers
Location (hall): 
Start/end time: 
Tuesday, July 2, 2019 - 15:45 to 17:15
Adesh Kumar

Adesh Kumar Singh1, Jeyakumar Kandasamy1

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

2-Deoxy aryl-C-glycoside motifs were found in various bio-active molecules and natural products [1]. For instance, the natural products pluramycins, angucyclines and benzoisochromanequinones contain 2-deoxy aryl C-glycoside units. There are few different routes have been developed for the preparation of 2-deoxy aryl glycosides [1]. Among them, a direct coupling of aryl donors such as arylboronic acids, arylhydrazines and aryl halides with glycals has received great attention in carbohydrate synthesis [2]. However, all these methods require a high temperature, dry reaction conditions and longer reaction temperatures. Aryldiazonium salts are highly useful synthetic intermediates in organic chemistry [3]. Aryldiazonium salts have been explored as an efficient alternative to arylhalides and arylboronic acids in many cross-coupling reactions [3a]. In this context, here we report palladium catalyzed tert-butyl nitrite mediated stereoselective synthesis of 2-deoxy aryl-C-glycosides from glycals and anilines under mild conditions (Scheme 1). A wide range of glycals including D-glucal, D-galactal, L-rhamanal, D-xylal and D-ribal reacted with various functionalized anilines and provided synthetically useful 2,3-deoxy 3-keto α- or β-aryl-C-glycosides in good to excellent yields in the absence of oxidant, base or ligand [4]. 

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) Roglans,A.; Pla-Quintana, A.; Moreno-Manas, M. Chem. Rev., 2006, 106, 4622-4643; (b) Mo, F. Y.; Dong, G. B.; Zhang, Y.; Wang, J. B. Org. Biomol. Chem., 2013, 11, 1582-1593.
  4. Singh, A .K.; Kandasamy, J. Submitted, 2019 (a) Singh, A .K.; Kandasamy J. Org. Biomol. Chem., 2018,16, 5107-5112.