Diphenyl Ether → HCID 22282664, compound

Participants

Reaction Steps

7,8-Dihydrothieno[2,3-g]indole, 5,6-dihydrothieno[3,2-f] and 5,6-dihydrothieno[2,3-e]indole were prepared according to the method described in Example 3, using the above mixture of dihydrothienoindole-2-carboxylic acids (1.64 g, 7.48 mmol), with the following modification. After the mixture had been passed down the heptane-packed column and the phenyl ether flushed-off with heptane, the eluant was increased to heptane-dichloromethane (1:1→1:3) to afford a purple solid. The solid was recrystallised [heptane-isopropyl ether (1:1)] to afford a mixture (2:3) of 7,8-dihydrothieno[2,3-g]indole and 5,6-dihydrothieno[3,2-f]indole (540 mg, 41%) as a pink solid. The filtrate was evaporated to afford a mixture (25:30:45) of 7,8-dihydrothieno[2,3-g]indole, 5,6-dihydrothieno[3,2-f]indole and 5,6-dihydrothieno[2,3-e]indole (644 mg, 49%) as a purple solid which was used without further purification.

Provenance & Evidence