Abstract
a four-step synthesis of monoalkylated benzidin is reported for immunogen preparation against benzidin dye. Use of 10% H2SO4/ dioxan for N-Boc cleavage avoids the cyclisation of 4-benzidinyl butyric acid into the corresponding lactam observed with the classical TFA/ CH2Cl2 system.
Notes
EC Directive relating quality of water intended for human consumption (80/778/EEC), Off. J. Eur. Commun., L229/11
Data of lactam 5:
1H NMR (DMSO) δ: 2.08 (quint., J = 7.5 Hz, 2 H, CH2CH 2CH2), 2.5 (CH 2CO, with DMSO), 3.86 (t, J=6.8 Hz, 2H, CH 2N), 7 (d, J=8.6 Hz, 2 Har), 7.6 (m, Har).
MS (IC+NH3) m/z: 253 [MH+].