To a solution of 3-(1-oxo-1,3,3′,4′-tetrahydro-1′H-spiro[indene-2,2′-naphthalene]-6-yl)benzonitrile (35 mg, 0.1 mmol) in DCM (5 mL) was added TiCl4 (76 mg, 0.4 mmol) dropwise, the mixture was stirred at 50° C. at Ar2 under microwave for 5 minutes, N,N′-methanediylidenebis(1,1,1-trimethylsilanamine) (74 mg, 0.4 mmol) was added dropwise. The mixture was stirred at 60° C. at Ar2 under microwave for 10 minutes and poured into ice-water (10 mL). The aqueous layer was extracted with CH2Cl2, which was combined with the organic layer. The organic layer was dried and concentrated to give crude (Z)—N-(5-(3-cyanophenyl)-3′,4′-dihydro-1′H-spiro[indene-2,2′-naphthalene]-3(1H)-ylidene)cyanamide (50 mg, 93%).
