反应详情

To a solution of methanesulphonamide (79.6 mg, 0.837 mmol) and bis[(2,2-dimethylpropanoyl)oxy](phenyl)-lambda-3-iodane (630.0 mg, 1.553 mmol) in isopropyl acetate (6.0 mL) was added 4-[(3,4-dichlorobenzyl)oxy]-2-methoxybenzaldehyde (Preparation 25, 300.0 mg, 0.963 mmol) and 4 Å molecular sieves (500.0 mg). The reaction mixture was stirred for 5 minutes producing a thick suspension. 3,3′-(1,3-Phenylene)bis(2,2-dimethylpropanoic acid)-dirhodium(Rh—Rh) (2:1) (13 mg, 0.017 mmol) was added in one portion and the resulting mixture stirred at room temperature for 10 minutes. 1,2-dichloroethane (5 mL) was then added producing a green solution, which was stirred for further 18 hours under a nitrogen atmosphere at room temperature. The reaction mixture was then concentrated in vacuo and partitioned between DCM and aqueous solution of hydrochloric acid (2 M). The combined organics were dried through a phase separation Cartridge™ and evaporated in vacuo. The resulting residue was purified by silica gel chromatography eluting with 0 to 60% EtOAc in heptane to yield the title compound as pale yellow gum which solidified upon standing (140 mg, 41% yield):

1. customproducing a thick suspension
2. stirringthe resulting mixture stirred at room temperature for 10 minutes
3. customproducing a green solution, which
4. stirringwas stirred for further 18 hours under a nitrogen atmosphere at room temperature
5. concentrationThe reaction mixture was then concentrated in vacuo
6. custompartitioned between DCM and aqueous solution of hydrochloric acid (2 M)
7. customThe combined organics were dried through a phase separation Cartridge™
8. customevaporated in vacuo
9. customThe resulting residue was purified by silica gel chromatography
10. washeluting with 0 to 60% EtOAc in heptane