Tetrahydrofuran → Indole

To a solution of 1 (473 mg, 1.40 mmol) in THF (6.5 mL) at −78° C. was added dropwise a 1.8 M solution of LDA in THF (1.71 mL, 3.08 mmol) and the reaction stirred for 1 hour, then methylcyanoformate (0.244 mL, 3.08 mmol) added dropwise and the reaction was stirred for 1 hour. The reaction was quenched by the addition of satd NH4Cl (10 mL), the layers separated, and the aqueous extracted with Et2O (3×10 mL). The combined organics were dried (MgSO4), filtered and concentrated in vacuo. The residue was purified on silica gel gradiently eluted with 20 to 30% EtOAc/hexanes to give 2 (153 mg, 28% yield) as an off-white solid. Rt=1.83 min using Phenomenex 30×4.6 5u column with flow rate of 5 mL/min over 2 min gradient. 0 to 100% B. Solvent A=10/90/0.1% MeOH/H2O/TFA. Solvent B=90/10/0.1%. [M+H]=396.

1. stirringthe reaction was stirred for 1 hour
2. customThe reaction was quenched by the addition of satd NH4Cl (10 mL)
3. customthe layers separated
4. extractionthe aqueous extracted with Et2O (3×10 mL)
5. dry with materialThe combined organics were dried (MgSO4)
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe residue was purified on silica gel
9. washgradiently eluted with 20 to 30% EtOAc/hexanes

ORD record

ord-8a455cc3c71a4ef8bcc5c516c39b6b18

Source dataset

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08357704B2