Synthesis
The general procedure for the synthesis of 6-mercapto-6-deoxy-β-cyclodextrin from mono-6-O-(p-toluenesulfonyl)-β-cyclodextrin is as follows: to a 50 mL round-bottomed flask equipped with a magnetic stirring bar and Schlenk fittings were added 1.00 g (0.776 mmol) of mono-6-O-(p-toluenesulfonyl)-β-cyclodextrin, 0.59 g (7.75 mmol) thiourea (purchased from Aldrich) and 7.8 mL of 0.1 N NaOH solution. The resulting mixture was heated and stirred at 80 °C for 6 h under nitrogen protection. Subsequently, 0.62 g (15.5 mmol) of sodium hydroxide was added and the reaction continued to be heated at 80 °C and under nitrogen atmosphere for 1 hour. After the reaction mixture was cooled to room temperature, the pH was adjusted to 4.0 with 10% HCl solution. the total volume of the reaction solution was adjusted to 20 mL, which was subsequently cooled in an ice bath, and 0.8 mL of tetrachloroethylene was added. The reaction mixture was stirred vigorously at 0 °C for 0.5 h. The precipitated solid was collected through a fine glass feed funnel. The resulting solid was vacuum dried overnight to yield 0.60 g (67% yield) of white amorphous solid product.
References
[1] Chemistry - A European Journal, 2014, vol. 20, # 35, p. 10944 - 10952
[2] Patent: EP1133318, 2007, B1. Location in patent: Page/Page column 32-33
[3] Chinese Journal of Chemistry, 2017, vol. 35, # 7, p. 1125 - 1132
[4] Chemical Communications, 2011, vol. 47, # 45, p. 12388 - 12390
[5] Angewandte Chemie - International Edition, 2012, vol. 51, # 2, p. 450 - 454
