[Synthesis]
The general procedure for the synthesis of methyl 2-(5-hydroxy-1-indenyl)acetate from the compound (CAS: 1187199-58-1) is as follows:
1. a mixture of methyl 2-(5-(benzyloxy)-2,3-dihydroinden-1-ylidene)acetate (5.3, 3.44 g, 11.7 mmol) with Pd-C (1.38 g, 11.7 mmol) in methanol (35 mL) was stirred for 3 hours under hydrogen atmosphere.
2. Upon completion of the reaction, the mixture was filtered through silica gel to remove the Pd-C catalyst.
3. After the solvent was removed under pressure, the residue was purified by silica gel column chromatography (eluent: ethyl acetate/hexane, 1:2) to afford the racemic product in 47% yield.
4. Separation of the racemic product using a chiral column (OD column, eluent: 4% isopropanol/hexane) afforded (R)-2-(5-hydroxy-2,3-dihydro-1H-inden-1-yl)methyl acetate (31.1, 0.324 g, retention time: 23.9 min, >99% ee) and (S)-2-(5-hydroxy-2,3-dihydro-1H-inden-1-yl)acetic acid (31.1, 0.324 g, retention time: 23.9 min, >99% ee). -yl)acetic acid methyl ester (31.2, 0.315 g, retention time: 30.4 min, >99% ee).
For the steps of Synthesis 5.4:
1. a mixture of methyl 2-(5-(benzyloxy)-2,3-dihydroinden-1-ylidene)acetate (5.3, 3.44 g, 11.7 mmol) with Pd-C (1.38 g, 11.7 mmol) in methanol (35 mL) was stirred for 3 hours under hydrogen atmosphere.
2. Upon completion of the reaction, the mixture was filtered through silica gel to remove the Pd-C catalyst.
3. After the solvent was removed under pressure, the residue was purified by silica gel column chromatography (eluent: ethyl acetate/hexane, 1:2) to afford the racemic product in 47% yield.
4. Separation of the racemic product using a chiral column (OD column, eluent: 4% isopropanol/hexane) gave 5.4 (>99% ee). |