To a 1-L four necked flask carrying a mechanical stirrer, Dean-stark apparatus (to remove traces of moisture in limonene), nitrogen inlet, thermometer pocket and an addition flask, 10% Pd-C (20 g) was charged under nitrogen atmosphere followed by benzphthalide (200 g, 0.9 mol). Under a slow stream of nitrogen, the temperature was raised to 170–180 ^oC. At about 100 ^oC, benzpthalide melts and stirring is possible. Once the temperature reaches 175 ^oC limonene (300 g, 2.2 mol) was added slowly over a period of 1 h (during addition, there is gentle reflux due to exothermic reaction). After the complete addition of limonene, reflux was continued for 2 h. The reaction mass was cooled to 50–60 ^oC during which the reaction mass solidifies. The solid was dissolved in acetone (1000 mL) and the reaction mixture was filtered under nitrogen. The filter cake containing the Pd-C catalyst was washed with acetone (50 mL). The combined filtrates were mixed and concentrated under reduced pressure. The residue was cooled to 10 ^oC, filtered and washed with a cold mixture of toluene: petroleum ether (3:7, 300mL) to gave 2 as a white crystalline solid. 175 g(86%). Which is bright white solid and practically pure by NMR.

White solid. Mp 130 – 132 oC , .

IR (KBr): 1685, 3155 cm-1 ,1H NMR (200 MHz, CDCl3): δ 2.94 (t, J = 8.0 Hz, 2H), 3.35 (t, J = 8.0 Hz, 2H), 7.15 – 7.51(m, 8H), 8.09(d, J = 9.0 Hz, 1H); 13C NMR (100 MHz, CDCl3): δ 37.6, 38.6, 126.4, 126.7, 128.6, 128.8, 129.0,132.0, 132.3, 133.5, 142.4, 145.3, 173.9.