1,5,6,7-Tetrahydro-4H-indol-4-one

Uses

• ;Reactant in synthesis of psammopemmin A as antitumor agent1• ;Reactant in synthesis of a 1,3,4,5-tetrahydrobenzindole β-ketoesters and tricyclic tetrahydrobenzindoles via C-H insertion reactions2• ;Reactant in preparation of tricyclic indole and dihydroindole derivatives as inhibitors of guanylate cyclase3• ;Reactant in preparation of condensed pyrroloindoles via Pd-catalyzed intramolecular C-H bond functionalization of (halobenzyl)pyrroles4• ;Reactant in enantioselective preparation of arylalkenyl indoles via asymmetric C-H insertion of rhodium carbenoids foll

Uses

1,5,6,7-Tetrahydro-4H-indol-4-one, is a versatile building block used for the synthesis of more complex pharmaceutical compounds. It can be used for the preparation of Psammopemmin A.

General Description

Iodination of 1,5,6,7-tetrahydro-4H-indol-4-one using 1-chloromethyl--4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetra-fluoroborate) yields α-iodo derivative as the main product.

Synthesis

The general procedure for the synthesis of 1,5,6,7-tetrahydro-4H-indol-4-one from 6,7-dihydro-4(5H)-benzofuranone is as follows: 6,7-dihydro-4(5H)-benzofuranone (0.10 g, 0.73 mmol) was dissolved in 20% aqueous ethanol (ca. 2 mL) along with the corresponding amine (3 equiv.) in an airtight tube at 150°C, respectively, and was Heating for 12 h or 36 h, respectively. Upon completion of the reaction, the reaction mixture was poured into water (10 mL) and the resulting aqueous solution was extracted with dichloromethane (3 x 10 mL). The organic extracts were combined, dried with anhydrous magnesium sulfate and concentrated to give a brown residue. This residue was purified by silica gel column chromatography with a solvent mixture of ethyl acetate/petroleum ether as eluent.

References

[1] Heterocycles, 1984, vol. 22, # 10, p. 2313 - 2316
[2] Tetrahedron Letters, 2012, vol. 53, # 33, p. 4276 - 4279
[3] Bulletin of the Korean Chemical Society, 2012, vol. 33, # 1, p. 341 - 343