Free TentaGel resin

A suspension of dry, PEG-free TentaGel resin 82 (see above) and quinoline toluenesulfonate (25 g, 83 mmol, 2.02 equiv.) in 1,2-dichloroethane (DCE) (1.5 L) was heated to reflux while continuously removing the solvent and traces of water. After about 500 mL of distillate had been collected, a solution of 2-bromo-l,l-diethoxyethane (50 mL, 332 mmol, 8.1 equiv.) in 1,2-dichloroethane (500 mL) was added and the mixture was maintained at reflux for 4 h with continuous removal of EtOH/DCE. Thereafter, the resin was washed with DMF (500 mL) and dioxane (500 mL) and then lyophilized to give the desired product 83 (98 g). The loading level was determined by quantification of bromine by elemental analysis (approximately 0.31 mmol g ). 

In a typical procedure, the PS-TentaGel Fmoc-protected amino resin was deprotected using 20% piperidine in DMF (Scheme 7.23). After transferring the free amino resin into an appropriate microwave vial, the resin was swollen in a mixture of a 1M solution of the corresponding aldehyde in DCM and a 1M solution ofthe corresponding carboxylic acid in methanol. After 30 min, a 1 M solution of the corresponding isonitrile in DCM was... 

Bromo-l-ethoxyethan-l-oxy)-linked TmtaGd resin (83) To remove residual poly (ethylene glycol) from the commercially available TentaGel HL-OH resin (130 pm, 0.41 mmol OH g ), a suspension of the resin (100 g, 41 mmol) in formic acid (500 mL, 13.3 mol) was stirred at 60 °C for 14 h. The mixture was then filtered, and the resin was thoroughly washed with dioxane (1.5 L) and then treated with 1 m NaOH (300 mL, 300 mmol). After 4 h, the resin was washed with water (1 L), MeOH (1.5 L), and dioxane (1.5 L) to give the PEG-free solid support. 

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