2-(Hydroxymethyl)-5-fluoroindane (I) was converted to bromide (II) upon treatment with CBr4 and PPh3. Alkylation of N-(diphenylmethylene)aminoacetonitrile (III) with bromide (II) under phase-transfer conditions furnished amino nitrile (V), which was reduced to diamine (VI) by using LiAlH4 in THF. Finally, condensation of diamine (V) with formamidine acetate yielded the target imidazoline.

In an alternative procedure, Wadsworth-Emmons condensation of 5-fluoroindan-2-one (VI) with triethyl phosphonoacetate gave the indeneacetate (VII), which was reduced to aldehyde (VIII) employing diisobutylaluminum hydride. Strecker reaction of aldehyde (VIII) with NaCN and NH-4-Cl produced amino nitrile (IX). This was reduced to diamine (X) using LiAlH4, and then condensed with formamidine acetate to produce imidazoline (XI). Finally, catalytic hydrogenation of indene (XI) over Pd/C provided the title indane derivative.