HCID 57475644, compound → HCID 57475651, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of vinylmagnesium chloride (6.86 mL, 10.97 mmol) at −78° C. under nitrogen atmosphere was added drop wise a solution of 2-bromo-7-iodo-9H-xanthen-9-one (2.00 g, 4.99 mmol) in THF (30 mL). The reaction mixture was allowed to slowly warm to −10° C., then the reaction was quenched with saturated NH4Cl. The mixture was extracted with EtOAc followed by a solvent mixture of CHCl3:i-PrOH (3:1). The combined organic layers were dried over Na2SO4 and concentrated under reduced pressure. The crude material was purified by filtration over silica gel (10% EtOAc/hexane) to give 2.14 g of 2-bromo-7-iodo-9-vinyl-9H-xanthen-9-ol as a white solid. Step 2: To a solution of 2-bromo-7-iodo-9-vinyl-9H-xanthen-9-ol (0.50 g, 1.16 mmol) and thiourea (0.18 g, 2.33 mmol) in acetic acid (2.00 mL) was added TFA (4.00 mL). The reaction mixture was stirred at RT overnight. The reaction mixture was concentrated under reduced pressure and extracted with EtOAc, followed by a solvent mixture of CHCl3:i-PrOH (3:1). The combined organic layers were dried over Na2SO4 and concentrated in vacuo. The residue was purified by chromatography (10%-100% EtOAc/hexane) to provide 0.36 g of 2′-bromo-7′-iodo-5,6-dihydrospiro[[1,3]thiazine-4,9′-xanthen]-2-amine as a light yellow solid.

Provenance & Evidence