Electric Literature of 21120-91-2,Some common heterocyclic compound, 21120-91-2, name is 7-Bromobicyclo[4.2.0]octa-1,3,5-triene, molecular formula is C8H7Br, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
In a 250 ml rbf with magnetic stir bar was added aminophenol (1 g, 1 eq), THF (15 ml) and KOtBu (1.23 g, 1.2 eq). The mixture was allowed to stir for 1 hour at room temperature. Bromo BCB (1.68 g, 1 eq) was added in THF (15 ml). The reaction was capped and allowed to stir for 12 h at room temperature. Water (100 ml) was then added. Ethyl acetate (3×100 ml) was used to extract the product from the aqueous phase. The combined organics were dried over sodium sulfate, filtered and concentrated in vacuo. The crude residue was subjected to a column of silica gel using heptanes and ethyl acetate (9:1) as eluent to give product (892 mg, 46%) as a dark oil. (0077) 1H NMR (500 MHz, Chloroform-d) delta 7.32 (dt, J=6.6, 4.3 Hz, 1H), 7.28-7.23 (m, 2H), 7.18 (d, J=7.4 Hz, 1H), 6.86 (d, J=9.0 Hz, 2H), 6.69 (d, J=9.0 Hz, 2H), 5.59 (dd, J=4.3, 2.1 Hz, 1H), 3.66 (dd, J=14.1, 4.3 Hz, 1H), 3.46 (br s, 2H), 3.28 (d, J=14.1 Hz, 1H). 13C NMR (126 MHz, Chloroform-d) delta 151.04, 145.18, 142.64, 140.49, 129.73, 127.29, 123.47, 123.00, 116.48, 116.36, 74.89, 39.47. DSC Showed an exotherm peak temperature at 179 C at a scan rate of 10 C/min.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 7-Bromobicyclo[4.2.0]octa-1,3,5-triene, its application will become more common.
Reference:
Patent; Rohm and Haas Electronic Materials LLC; Hayes, Colin; Gallagher, Michael K.; Riener, Michelle; (10 pag.)US2019/169327; (2019); A1;,
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