Reaction Steps
1,2-Bis-(4-cyanophenyl)ethane was prepared in one step from 2,3-bis-(4-bromophenyl)propanoic acid (Dann, O., (1971) Liebigs Ann. Chem., 749: 68-89) by the action of CuCN in DMF (Das, B. P., et al., (1977) J. Med. Chem., 20: 531-536) in a 50% yield; mp 195-197° C. 1H NMR (DMSO-d6): 7.68 (d, 4H, J=8), 7.40 (d, 4H, J=8), 3.01(s, 4H). 13NMR (DMSO-d6): 146.7, 131.9, 129.3, 118.6, 108.6, 35.8. MS m/e 232 (M++1).1,2-Bis-(4-cyanophenyl)ethane was used without further characterization and on treatment with DIBAL gave a white crystalline solid (CHCl3:ether) 76% mp 121-122° C. of 1,2-bis-(4-formylphenyl)ethane. 1H NMR (DMSO-d6): 9.96 (s, 2H), 7.80 (d, 4H, J=8), 7.44 (d, 4H J=8), 3.05 (s, 4H). 13C NMR (DMSO-d6/D2O): 192.0, 184.0, 134.2, 129.1, 128.8, 36.0. Anal. Calc. for C16H14O2.0.1H2O: C, 80.04; H, 5.96. Found: C, 80.09; H, 5.98. A protocol similar to that described above was employed for the condensation of 1,2-bis-(4-formylphenyl)ethane and 4-(N-isopropylamidino)-1,2-phenylene diamine (18, 35). A 75% yield of a purple solid mp>320° C. 1H NMR (DMSO-d6/D2O): 8.09 (d, 4H, J=8), 8.06 (s, 2H), 7.83 (d, 2H, J=8.4), 7.65 (d, 2H, J=8.4), 7.48 (d, 4H, J=8), 4.03 (br m, 2H), 3.07 (br, 4H), 1.29 (d, 12H, J=6). 13NMR (DMSO-d6/D2O): 162.4, 153.0, 146.6, 138.3, 135.4, 129.8, 127.9, 124.8, 124.1, 123.5, 115.5, 115.0, 45.6, 36.2, 21.2. MS (FAB) 583 (M++1)Anal. calc. for C36H38N8.4HCl.0.5H2O: C, 58.61; H, 5.87; N, 15.19. Found: C, 58.31; H, 5.79; N, 15.02.
