85% |
In dichloromethane; at 20℃; for 0.5h; |
To a clear solution of B(C6F5)3 (0.050 g, 0.098 mmol) in CH2Cl2 (5 mL) was added a colorless solution of <strong>[22034-13-5]4-bromo-benzo[2,1,3]thiadiazole</strong> (0.021 mg, 0.098 mmol) in CH2Cl2 (5 mL). The resulting yellow solution was allowed to stir for 30 minutes at room temperature. The solvent was removed in vacuo and the resulting solid washed with pentanes (2.x.10 mL) and dried under vacuum for 1 hour. The product was collected as a faint yellow solid. Recovered yield, 60 mg (85percent). Crystal's suitable for X-ray diffraction were grown via slow diffusion of pentane into a concentrated solution of 4 in CH2Cl2. Upon addition of excess B(C6F5)3 (3 equivalents total) to 4, no change in the 1H or 19F spectrum was observed from 25 to -50° C. 1H NMR (CD2Cl2): delta 8.02 (d, 3JH-H=8 Hz, 1H, benzothiadiazole-p-CH), 7.71 (dd, 3JH-H=8 Hz, 3JH-H=8 Hz, 1H, benzothiadiazole-m-CH), 7.50 (d, 3JH-H=8 Hz, 1H, benzothiadiazole-o-CH). {1H} NMR (CD2Cl2): delta -5.5 (bs). 13C{1H} NMR (CD2Cl2, -50° C.) partial: 152.79, (s, quaternary), 149.22 (s, quaternary), 148.90 (dm, 1JC-F=250 Hz, CF), 148.22 (dm, 1JC-F=250 Hz, CF), 146.55 (dm, 1JC-F=245 Hz, CF), 141.73 (dm, 1JC-F=245 Hz, CF), 140.85 (dm, 1JC-F=250 Hz, CF), 138.99 (dm, 1JC-F=240 Hz, CF), 137.05 (dm, 1JC-F=245 Hz, CF), 136.74 (s, benzothiadiazole-m-CH), 134.01 (s, benzothiadiazole-p-CH), 131.90 (dm, 1JC-F=250 Hz, CF), 117.22 (quaternary), 116.05 (s, benzothiadiazole-o-CH). 19F NMR (CD2Cl2): delta -125.2 (br, 1F, ortho-C6F5), -131.0 (br, 3F, ortho-C6F5), -135.2 (br, 1F, ortho-C6F5), -137.2 (br, 1F, ortho-C6F5), -154.5 (s, 1F, para-C6F5), -156.5 (br, 2F, para-C6F5), -161.6 (br, 2F, meta-C6F5), 163.8 (br, 4F, meta-C6F5). 19F NMR (CD2Cl2, -50° C.): delta -125.17 (m, 1F, 3JF-F=22 Hz, ortho-C6F5), -130.58 (m, 1F, 3JF-F=21 Hz, ortho-C6F5), -131.42 (m, 2F, 3JF-F=24 Hz, ortho-C6F5), -134.13 (m, 1F, 3JF-F=24 Hz, ortho-C6F5), -137.58 (m, 1F, 3JF-F=24 Hz, ortho-C6F5), -153.99 (m, 1F, 3JF-F=20 Hz, para-C6F5), -155.31 (m, 1F, 3JF-F=20 Hz, para-C6F5), -157.27 (m, 1F, 3JF-F=22 Hz, para-C6F5), -161.28 (m, 1F, 3JF-F=20 Hz, meta-C6F5), -162.91 (m, 1F, 3JF-F=20 Hz, meta-C6F5), -162.74 (m, 1F, 3JF-F=20 Hz, meta-C6F5), -163.33 (m, 1F, 3JF-F=20 Hz, meta-C6F5), -163.77 (m, 1F, 3JF-F=22 Hz, meta-C6F5), -164.03 (m, 1F, 3JF-F=22 Hz, meta-C6F5). UV-vis: lambdamax=355 nm. X-Ray: C24H3B1Br1F15N2S1. Space Group=P-1. Cell: a=10.82(15) , b=11.82(18) , c=12.36(18) , alpha=63.7(3)°, beta=75.1(3)°, gamma=84.1(4)°, V=1369(35) 3. R=0.0432percent, Rw=0.1132percent. GOF=1.027. |