Synthesis
The general procedure for the synthesis of 3-amino-6-bromopyridazine from 3,6-dibromopyridazine was as follows: 250 g (1.05 mol) of 3,6-dibromopyridazine was dissolved in 1.2 liters of a 25% ammonia solution, and the resulting solution was transferred to an autoclave. The reaction mixture was heated to 100 °C at a pressure of 11.7 bar and kept at this temperature for the reaction overnight. After completion of the reaction, the mixture was allowed to cool to room temperature and the precipitated solid product was collected by filtration. The solid was washed several times with deionized water to remove impurities and subsequently dried to afford 137 g (75% yield) of the target product 3-amino-6-bromopyridazine. The structure of the product was confirmed by 1H-NMR (DMSO-d6) with chemical shifts of δ = 6.58 (1H), 6.69 (2H), 7.41 (1H) ppm.
References
[1] Patent: WO2014/20041, 2014, A1. Location in patent: Page/Page column 137
[2] Patent: WO2014/131739, 2014, A2. Location in patent: Page/Page column 41
[3] Patent: WO2014/198776, 2014, A1. Location in patent: Page/Page column 79
[4] Patent: DE951929, 1953,
[5] Journal of the American Chemical Society, 1954, vol. 76, p. 3225
