Ammonium Chloride → Methyl 5-(2,4-dimethoxypyridin-3-yl)-5-(1,1-dimethylethylsulfinamido)pentanoate

Temperature

-78 °C

A cooled (−78° C.) yellow solution of commercially available 3-bromo-2,4-dimethoxypyridine (1.490 g; 6.83 mmol) in anh. THF (42 ml), under nitrogen, was treated dropwise with a solution of 1.6 M n-BuLi in hexanes (4.3 ml; 6.88 mmol). The resulting orange solution was further stirred at −78° C. for 10 min. A yellow solution of methyl 5-((tert-butylsulfinyl)imino)pentanoate (1.450 g; 6.21 mmol) in anh. THF (5 ml) was then added to the cooled reaction mixture, and stirring at −78° C. was continued for 65 min. The resulting orange reaction mixture was treated successively with aq. sat. NH4Cl (22 ml), Et2O (75 ml) and water (20 ml). The separated orange organic layer was then washed with brine (30 ml), dried over anh. MgSO4, filtered, and concentrated to dryness under reduced pressure. Purification by FC (DCM/MeOH=30/1) afforded methyl 5-(2,4-dimethoxypyridin-3-yl)-5-(1,1-dimethylethylsulfinamido)pentanoate as a yellow oil. LC-MS (conditions B): tR=0.75 min.; [M+H]+: 372.82 g/mol.

1. stirringstirring at −78° C.
2. waitwas continued for 65 min
3. washThe separated orange organic layer was then washed with brine (30 ml)
4. dry with materialdried over anh. MgSO4
5. filtrationfiltered
6. concentrationconcentrated to dryness under reduced pressure
7. customPurification by FC (DCM/MeOH=30/1)

ORD record

ord-59a851a4261b48e3b59bf950aed51108

Source dataset

uspto-grants-2016_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09242970B2