Synthetic Route of 42098-25-9, The chemical industry reduces the impact on the environment during synthesis 42098-25-9, name is 5-Chloro-1-methyl-4-nitro-1H-pyrazole, I believe this compound will play a more active role in future production and life.
Intermediate 2 5-(3A-Dihydro-2H-pyran-6-yl)-1-methyl-4-nitro-1H-pyrazole A mixture of 5-chloro-1-methyl-4-nitro-1H-pyrazole (200 mg, 1.25 mmol), potassium fluoride dihydrate (235 mg, 2.5 mmol) and 3,4-dihydro-2H-pyran-6-boronic acid pinacol ester (394 mg, 1.88 mmol) in THF (3 mL) was degassed by bubbling nitrogen through it for 15 min. Tris(dibenzylideneacetone)dipalladium/tri-tert-butyl phosphonium tetrafluoroborate mixture (mole ratio: 1/1.2, 151 mg, 0.13 mmol) was added and the mixture degassed for a further 10 min before being heated in the microwave at 85 C. for 2 hr. Water (10 mL) was added and the mixture extracted with EtOAc (3*5 mL). The combined organic layers were passed through a phase separation cartridge and concentrated under reduced pressure. Purification via silica gel chromatography (0-5% EtOAc/isohexane) gave 5-(3,4-dihydro-2H-pyran-6-yl)-1-methyl-4-nitro-1H-pyrazole as a yellow solid (215 mg, 82%). 1H NMR (400 MHz, CDCl3) delta 8.04 (s, 1H), 5.22 (t, J=3.9 Hz, 1H), 4.20 (t, J=5.1 Hz, 2H), 3.88 (s, 3H), 2.31-2.24 (m, 2H), 2.05-1.96 (m, 2H).
In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 5-Chloro-1-methyl-4-nitro-1H-pyrazole, other downstream synthetic routes, hurry up and to see.
Reference:
Patent; Genentech, Inc.; Burch, Jason; Sun, Minghua; Wang, Xiaojing; Blackaby, Wesley; Hodges, Alastair James; Sharpe, Andrew; US2014/88117; (2014); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics