Some common heterocyclic compound, 70951-85-8, name is 4-Bromo-1-(tert-butyl)-1H-pyrazole, molecular formula is C7H11BrN2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Product Details of 70951-85-8
A mixture of 4-bromo-1-tert-butyl-1H-pyrazole (3.3 g, 16.3 mmol), bis(pinacolato)diboron (8.3 g, 32.6 mmol), PdCl2(dppf) (1.8 g, 2.4 mmol), and KOAc (3.2 g, 32.6 mmol) in 1,4-dioxane (60 mL) was heated at reflux for 15 hours. After the completion of the reaction, the mixture was filtered and the filter cake was washed with EtOAc (100 mL). The filtrate was concentrated under reduced pressure. The residue was purified by silica gel chromatography using heptane/ethyl acetate (10% to 50%) as eluting solvents to afford 1-tert-butyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole as white solid (1.0 g, 25%). MS (ESI) m/z: 251 [M+H]+.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 70951-85-8, its application will become more common.
Reference:
Patent; F. HOFFMANN-LA ROCHE AG; GENENTECH, INC.; DO, Steven; HU, Huiyong; KOLESNIKOV, Aleksandr; TSUI, Vickie, H.; WANG, Xiaojing; WO2014/1377; (2014); A1;,
Pyrazole – Wikipedia,
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