Dimethylformamide → 4,5,6,7-tetrahydro-1H-indole-2-carbaldehyde

関与物質

反応手順

Anhydrous DMF 20 mL in a 250 mL flask was cooled on ice bath and neat POCl3 4.6 mL (50 mmol) was added dropwise under Ar. After 10 min, a solution of tetrahydroindole 3.83 g (32.14 mmol) in anh DMF 10 mL was gradually added over 10 min (exothermic) followed by additional anh DMF 2×5 mL to wash the flask and the syringe. The cooling bath was replaced with ambient water bath and the reaction was stirred at RT under Ar for 13 hours (overnight). The reaction was quenched by addition of water 20 mL followed by 15% wt NaOH solution 40 mL. After 10 min, additional 15% NaOH 25 mL was added, followed by water 100 mL and the mixture was stirred vigorously for 30 min on ambient water bath. The precipitated product was collected by filtration, compressed on the Buchner funnel, washed thoroughly with water, dried by suction and on highvac. Y=4.282 g (90.5%) of light tan shiny flakes. 1H-NMR (d6-DMSO, 400 MHz): 11.609 (br s, 1H), 9.268 (s, 1H), 6.679 (s, 1H), 2.557 (t, 5.9 Hz, 2H), 2.446 (t, 5.9 Hz, 2H), 1.693 (m, 4H)

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