1,1-Dibromoethane → HCID 21709880, compound

Participants

Reaction Steps

To an ice-cooled solution of 2-(cyclohexyldimethylsiloxy)indene (13.62 g, 50.0 mmol) in THF (50 mL) was added dropwise n-BuLi (20.0 mL of a 2.5 M solution in hexanes, 50.0 mmol) and the reaction mixture was stirred overnight at room temperature. The resulting solution was then cooled to −80° C. and treated dropwise with a solution of dibromoethane (4.70 g, 25.0 mmol) in THF (30 mL). The reaction mixture was gradually warmed to room temperature, stirred overnight and washed with saturated ammonium chloride solution (150 mL). The organic phase was dried over sodium sulfate. Solvents were evaporated and the remaining oil was dissolved in Et2O (100 mL). Repeated crystallizations gave a total yield 4.03 g (28.2%) of the title compound as off-white crystals. The first crystalline fraction was used for spectral characterization. EIMS (calcd/found): m/e 570.3349/570.3342. 1H NMR (CDCl3, δ): 7.19-7.07 (m, 6H); 6.99 (td, 3J=7.3 Hz, 4J=1.3 Hz, 2H), 5.65 (s, 2H); 3.17 (m, 2H); 1.84-1.79 (m, AA′, 2H); 1.73 (m, 10H); 1.59-1.54 (m, BB′, 2H); 1.20 (m, 10H); 0.84 (m, 2H); 0.22 (s, 6H); 0.22 (s, 6H). 13C NMR (CDCl3, δ): 164.98; 144.47; 140.65; 126.51; 122.52; 122.33; 118.72; 104.64; 49.09; 27.72; 26.80; 26.48; 26.37; 24.29; −3.60.

Provenance & Evidence