Evaluation and Removal of Production Process Constraints in the Synthesis of 3,5-Dibromopyrazole
作者:Katie Brown、Yun Huang、Kevin Knopf、Bryan Li、Martha A. Ornelas、Rebecca B. Watson
DOI:10.1021/acs.oprd.3c00309
日期:2024.1.19
Multiple methods for the preparation of 3,5-dibromopyrazole are described. While 3,5-dibromopyrazole is readily available on a kilogram scale, an internal demand facilitated the need to expand the vendor pool, with an overall goal of lowering cost. To pursue this goal, we focused on developing synthetic methods in the operating temperature range of −20 to 120 °C to remove production process constraints
描述了多种制备3,5-二溴吡唑的方法。虽然3,5-二溴吡唑很容易以公斤级供应,但内部需求促进了扩大供应商池的需要,总体目标是降低成本。为了实现这一目标,我们重点开发-20至120°C操作温度范围内的合成方法,以消除生产工艺限制,并探索连续流动程序用于3,4,5-三溴吡唑区域选择性脱卤的选择。另一种方法是从吡唑-3-甲酸酯的溴化开始,然后进行一锅皂化和脱羧,也被发现是有效的。