(Diethylamino)sulfur trifluoride → 6-(4-tert-butyl-phenyl)-2-fluoromethyl-5H-pyrazolo[1,5-a]pyrazin-4-one

HRID 2272977Notes

Reaction equation

[C:1]([C:5]1[CH:10]=[CH:9][C:8]([C:11]2[NH:12][C:13](=[O:22])[C:14]3[N:15]([N:17]=[C:18]([CH2:20]O)[CH:19]=3)[CH:16]=2)=[CH:7][CH:6]=1)([CH3:4])([CH3:3])[CH3:2].C(N(S(F)(F)[F:29])CC)C>ClCCl>[C:1]([C:5]1[CH:10]=[CH:9][C:8]([C:11]2[NH:12][C:13](=[O:22])[C:14]3[N:15]([N:17]=[C:18]([CH2:20][F:29])[CH:19]=3)[CH:16]=2)=[CH:7][CH:6]=1)([CH3:4])([CH3:3])[CH3:2]

Participants

Conditions

Temperature: -78 °C

Procedure

A suspension of 149 mg (0.50 mmol) 6-(4-tert-butyl-phenyl)-2-hydroxymethyl-5H-pyrazolo[1,5-a]pyrazin-4-one in 1.25 ml dichloromethane is cooled to −78° C. Then 264 μl (2.00 mmol) diethylaminosulfurtrifluoride are added. The reaction mixture is allowed to reach room temperature over 30 minutes. The reaction mixture is evaporated and the residue is treated with water and saturated sodium hydrogen carbonate solution. The solids are filtered off and chromatographed on a silica gel column with cyclohexane/ethyl acetate as eluent to afford 6-(4-tert-butyl-phenyl)-2-fluoromethyl-5H-pyrazolo[1,5-a]pyrazin-4-one as white powder; HPLC/MS 2.80 min (B), [M+H] 300; 1H NMR (400 MHz, DMSO-d6) δ 11.57 (s, 1H), 8.03 (s, 1H), 7.73-7.64 (m, 2H), 7.55-7.46 (m, 2H), 7.15 (d, J=2.0 Hz, 1H), 5.52 (d, J=48.1 Hz, 2H), 1.32 (s, 9H).

Workup

customThe reaction mixture is evaporated
additionthe residue is treated with water and saturated sodium hydrogen carbonate solution
filtrationThe solids are filtered off
customchromatographed on a silica gel column with cyclohexane/ethyl acetate as eluent

Sources & evidence

ORD record: ord-b2174e95f19a4d38af3e923d059b0948
Source dataset: uspto-grants-2015_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09120805B2

Reaction notes

Loading…