Hydroquinones solid support

Method 1. Cool a solution of 33 g (0.33 mol) of hydroquinone in 150 ml of 60 per cent acetic acid contained in a 600-ml beaker to below 5 °C in an ice bath. Dissolve 42 g (0.42 mol) of chromium trioxide in 70 ml of water, and add 30 ml of glacial acetic acid. By means of a separatory funnel with bent stem and supported over the beaker, add the chromium trioxide solution to the mechanically stirred hydroquinone solution at such a rate that the temperature does not rise above 10 °C the addition takes about 2 hours. Filter the mixture at once and wash the quinone several times with 10 ml portions of ice-cold water. Spread the material upon filter paper until dry, but no longer or the quinone will be lost through sublimation. The yield of quinone (a bright yellow crystalline solid), m.p. 115 °C, is 21 g (66%) it darkens when exposed to light. 

Place 6 g of 1,4-dimethoxybenzene (hydroquinone dimethyl ether) in a 125-mL Erlenmeyer flask, add 10 mL of /-butyl alcohol and 20 mL of acetic acid, and put the flask in an ice-water bath to cool. Measure 10 mL of concentrated sulfuric acid into a 50-mL Erlenmeyer flask, add 10 mL of 30% fuming sulfuric acid or 20 mL of concentrated sulfuric acid, and put the flask, properly supported, in the ice bath to cool. For good thermal contact the ice bath should be an ice-water mixture. Put a thermometer in the larger flask and swirl in the ice bath until the temperature is in the range 0-3°C, and remove the thermometer (solid, ifpresent, will dissolve later). Don t use the thermometer as a stirring rod. Clamp a small separatory funnel in a position to deliver into the 125-mL Erlenmeyer flask so that the flask can remain in the ice-water bath, wipe the smaller flask dry, and pour the chilled sulfuric acid solution into the funnel. While swirling the 125-mL flask in the ice bath, run in the chilled sulfuric acid by rapid drops during the course of 4-7 min. 

Pon RT, Yu S, Guo Z, Sanghvi Y. Multiple oligodeoxynucleotide syntheses on a reusable solid-phase CPG support via the hydroquinone-0,0 -diacetic acid (Q-linker) linker arm. Nucleic Acids Res 27 1531-1538, 1999. 

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