Dimethyl Sulfoxide → 1-(tetrahydro-2H-pyran-2-yl)-1H-benzo[d]imidazole-5-carbaldehyde

Temperature

-70 °C

To a solution of oxalyl chloride (1.17 g, 9.23 mol) in DCM (10 mL) at −70° C. was added dropwise DMSO (1.41 g, 18.09 mmol). The reaction mixture was stirred at −70° C. for 30 min. To the resulting solution was added dropwise over 30 min a solution of 24 (1.4 g, 6.03 mmol) in DCM (20 mL). After the addition the reaction temperature was raised to −55° C. The reaction was stirred for 1 h while the temperature was maintained between −55° C. and −45° C., then DIPEA (6.0 mL) was added dropwise over 5 min. The reaction mixture was warmed to 0° C. over 10 min then quenched with 1 M HCl (50 mL). The organic layer was separated, dried (MgSO4), filtered and concentrated in vacuo to afford 1.0 g (72%) of 1-(tetrahydro-2H-pyran-2-yl)-1H-benzo[d]imidazole-5-carbaldehyde (64) as red oil: MS (ESI) m/z=231.1 [M+1]+.

1. additionAfter the addition the reaction temperature
2. temperaturewas raised to −55° C
3. stirringThe reaction was stirred for 1 h while the temperature
4. temperaturewas maintained between −55° C. and −45° C.
5. temperatureThe reaction mixture was warmed to 0° C. over 10 min
6. customthen quenched with 1 M HCl (50 mL)
7. customThe organic layer was separated
8. dry with materialdried (MgSO4)
9. filtrationfiltered
10. concentrationconcentrated in vacuo

ORD record

ord-ba20733ca1c448d8b33cf5ae47de6757

Source dataset

uspto-grants-2014_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08637537B2