合成路线1

The condensation of 6-methoxyindan-1-one (I) with phosphonate (II) by means of NaH in THF gives 2-(6-methoxyindan-1-ylidene)acetonitrile (III), which is hydrogenated with h2 over Raney Co in ethanol/NH3 to yield 2-(6-methoxyindan-1-ylidene)ethylamine (IV). The acylation of (IV) with propionyl chloride (V) and TEA in THF affords the corresponding amide (VI), which is submitted to an asymmetric reduction with H2 and a chiral Ru catalyst to provide N-[2-(6-methoxyindan-1(S)-yl)ethyl]propionamide (VII). The bromination of (VII) with Br2 and NaOAc in methanol gives the 5-bromo derivative (VIII), which is demethylated by means of BBr3 in dichloromethane to yield the hydroxy compound (IX). The reaction of (IX) with allyl bromide (X) by means of NaH in DMF affords the allyl ether (XI), which is submitted to a Claisen rearrangement in N,N-diethylaniline at 200 C to provide the 7-allyl derivative (XII).The reaction of (XII) with ozone in methanol gives the acetaldehyde derivative (XIII), which is reduced with NaBH4 in methanol to yield the ethanol derivative (XIV). The hydrogenolysis of the Br substituent of (XIV) by means of H2 over Pd/C in methanol/TEA affords the dihydroxy compound (XV), which is treated with MsCl and pyridine to provide the mesylate (XVI). Finally, this compound is cyclized by means of TEA in refluxing ethyl acetate to furnish the target indeno[5,4-b]furan derivative.

合成路线2