Ethanethiol → Methyl (2S)-2-[(1S)-5-hydroxy-2,3-dihydro-1H-inden-1-yl]butanoate

Participants

Reaction Steps

To a cold solution (ice water bath) of the compound prepared in Example 6 (233 g, 0.94 mol) in 2.5 L CH2Cl2, was added AlCl3 (630 g, 4.7 mol) slowly under Ar. The pot temperature was kept below 20° C., and the color of the reaction turned purple. EtSH (345 mL, 4.7 mol) was added slowly via an addition funnel to the reaction mixture, and the inside temperature was kept below 15° C. After 2 hours of stirring at below 20° C., the reaction went to completion by NMR analysis. The pot mixture was slowly poured into 2.5 L ice water with a strong agitation. The organic layer was separated, and the aqueous layer was extracted with 1 L CH2Cl2. The combined CH2Cl2 layers were washed with water (4×1 L) until pH 6.0-7.0, and then dried over Na2SO4. The product (216 g, 98%) was obtained as a white solid after solvent removal and vacuum drying. 1H NMR (DMSO-d6) δ 9.10 (s, 1H), 6.78 (d, 1H), 6.58 (d, 1H), 6.50 (dd, 1H), 3.60 (s, 3H), 3.20 (q, 1H), 2.70 (m, 2H), 2.40 (m, 1H), 2.08 (m, 1H), 1.80 (m, 1H), 1.50 (m, 2H), 0.80 (t, 3H).

Provenance & Evidence