Sodium hydride → HCID 58914778, compound

Participants

Reaction Steps

Dry ether was added to NaH (1.5 eq as the oil dispersion) under argon. After decanting off the ether via syringe, the NaH was suspended again with fresh ether under argon. A solution of TOSMIC (1.1 eq) and 2 (1 eq) dissolved in a mixture of ether and DMSO was added dropwise to the stirred suspension of NaH at 0° C. over 20-30 min. The addition was mildly exothermic and evolved gas. After the addition, the reaction was allowed to warm to ambient rt. The progress of the reaction was followed by TLC (25% EtOAc/Hexane, the UV active product was at Rf=0.4) and LCMS until done (−2-3 h). Upon completion, the reaction was carefully quenched with sat. aq. NH4Cl (added slowly to avoid strong gas evolution and exotherm) and diluted with ether. The layers were separated and the organic phase washed with sat. aq. NaHCO3, water, and brine. The crude dark solid can be purified by recrystallization. Best results were achieved either through recrystallization directly from a mixture of hot EtOAc/hexane (1:3 v/v) or by dissolving the crude product in minimal hot EtOAc followed by addition of hexane (−2 volumes of hexane based on the volume of EtOAc). The hot solutions were allowed to cool to room temperature and age over night. The crystals were first filtered and then washed with hexane giving 99% pure product in 60-70% yield.

Provenance & Evidence