Triisopropyl borate → 1,3-Dimethyl-2,4-dioxo-6-(2-(tritylthio)ethyl)-2,3,4,6-tetrahydro-1H-pyrrolo[3,4-d]pyrimidin-5-ylboronic acid

Participants

Reaction Conditions

Reaction Steps

1,3-Dimethyl-6-(2-(tritylthio)ethyl)-1H-pyrrolo[3,4-d]pyrimidine-2,4(3H,6H)-dione (step 2)(3.6 g, 7.47 mmol) was dissolved in anhydrous THF (67.3 mL) at room temperature in an oven dried flask. The flask was evacuated and backfilled with nitrogen (×3) and cooled to −78° C. LDA (0.719 M, 16.63 mL, 11.96 mmol) was added over 10 mins followed by triisopropyl borate (2.76 mL, 11.96 mmol) and the reaction aged for 2 hr at −78° C. The reaction was quenched with saturated NH4Cl solution (60 mL) added via syringe under nitrogen and the mixture was warmed to room temperature and stirred overnight under nitrogen. The mixture was then diluted DCM (400 mL). The layers were separated and the aqueous extracted with DCM (2×100 mL). The combined organics were passed through a hydrophobic frit and the solvent was reduced to ˜20 mL under reduced pressure and EtOAc (100 mL) added to the resulting red oil. Reduction of solvent volume under reduced pressure to ˜25 mL afforded precipitation of a white solid. The solid was collected by reduced pressure filtration, washed with EtOAc (10 mL) and dried under vacuum 50° C. for 16 h to afford the title compound;

Provenance & Evidence