Tetrahydrofuran → N-phenyl-7-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,3-dihydro-1H-inden-1-amine

Participants

Reaction Steps

To a solution of 2.50 g (8.70 mmol) of 7-bromo-N-phenyl-2,3-dihydro-1H-inden-1-amine in 50 ml THF 3.50 ml (8.70 mmol) of 2.5M nBuLi in hexanes was added at −80° C. in argon atmosphere. The reaction mixture was then stirred for 1 h at this temperature. Further on, 11.1 ml (17.8 mmol) of 1.7M tBuLi in pentane was added, and the reaction mixture was stirred for 1 h. Then, 3.23 g (17.4 mmol) of 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane was added. After that the cooling bath was removed, and the resulting mixture was stirred for 1 h at room temperature. To the formed mixture 10 ml of water was added, and the resulting mixture was evaporated to dryness. The residue was diluted with 200 ml of water, and the title product was extracted with 3×50 ml of ethyl acetate. The combined organic extract was dried over Na2SO4 and evaporated to dryness. Yield 2.80 g (96%) of a light yellow oil. Anal. calc. For C21H26BNO2: C, 75.24; H, 7.82; N, 4.18. Found: C, 75.40; H, 8.09; N, 4.02. 1H NMR (CDCl3): δ 7.63 (m, 1H, 6-H in indane); 7.37-7.38 (m, 1H, 4-H in indane); 7.27-7.30 (m, 1H, 5-H in indane); 7.18 (m, 2H, 3,5-H in phenyl); 6.65-6.74 (m, 3H, 2,4,6-H in phenyl); 5.20-5.21 (m, 1H, 1-H in indane); 3.09-3.17 (m, 1H, 3- or 3′-H in indane); 2.85-2.92 (m, 1H, 3′- or 3-H in indane); 2.28-2.37 (m, 1H, 2- or 2′-H in indane); 2.13-2.19 (m, 1H, 2′- or 2-H in indane); 1.20 (s, 6-H, 4,5-Me in BPin); 1.12 (s, 6H, 4′,5′-Me in BPin).

Provenance & Evidence