Diisopropylethylamine → PyBrOP DIPEA

Participants

Reaction Steps

The scaffold (3 eq), bromo-tris-pyrrolidino-phosphonium hexafluorophosphate (4 eq) were dissolved in N,N-dimethylformamide (2 mL) or dichloromethane/N-methyl-2-pyrrolidone (2 mL, 19:1) and added to the resin. N,N-diisopropylethylamine (9 eq) was added and the reaction mixture was agitated for 3 hours at room temperature, however, some scaffolds were agitated for 18 hours. The reagents were removed from the resin and the resin was washed with dichloromethane (5 mL), methanol (5 mL), and N,N-dimethylformamide (5 mL). A Kaiser test was performed and, if negative (i.e., no free amine present), the resin was deemed suitable for further transformation. The resulting resins were dried under vacuum prior to deprotection/cleavage.

Provenance & Evidence