Methanol → 6-Hydroxymethylindole

A stirred solution of methyl indole-6-carboxylate (50 g) (see Example 1, part b) in dry toluene (1 liter), in a three-necked three-liter flask fitted with a mechanical stirrer, thermometer and dropping funnel, was cooled to -70° under an atmosphere of nitrogen, and treated dropwise with a solution of diisobutylaluminum hydride (381 ml of 1.5M solution in toluene) over 50 min. After 2.5 hr a further portion of diisobutylaluminum hydride (25 ml) was added dropwise, and the mixture stirred for a further 30 min. Methanol (100 ml) and saturated aqueous sodium sulfate (100 ml) were added sequentially, at -78°. The cooling bath was removed, the reaction allowed to warm to room temperature, and 6M hydrochloric acid (25 ml) was added dropwise. The mixture was filtered through a pad of diatomaceous earth, the filter cake washed with toluene and water, the organic phase separated and washed with water, dried (MgSO4) and evaporated to give 6-hydroxymethylindole (34.2 g, 82%) as an oil which slowly solidified; partial NMR (250 MHz, CDCl3): 1.73(s, 1H, CH2OH), 4.78(s, 2H, CH2OH), 6.55(m, 1H, H3 -indole), 8.20(br s, 1H, NH).

1. temperaturewas cooled to -70° under an atmosphere of nitrogen
2. customThe cooling bath was removed
3. addition6M hydrochloric acid (25 ml) was added dropwise
4. filtrationThe mixture was filtered through a pad of diatomaceous earth
5. washthe filter cake washed with toluene and water
6. customthe organic phase separated
7. washwashed with water
8. dry with materialdried (MgSO4)
9. customevaporated

ORD record

ord-a50f25f761ef46559ce4430255f5a1e9

Source dataset

uspto-grants-1990_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04894386