2-Methoxyethyl chloroformate → 2-Methoxyethyl 4-(3-bromopyrazolo[1,5-a]pyrimidin-5-yl)piperazine-1-carboxylate
Reaction equation
[Br:1][C:2]1[CH:3]=[N:4][N:5]2[CH:10]=[CH:9][C:8]([N:11]3[CH2:16][CH2:15][NH:14][CH2:13][CH2:12]3)=[N:7][C:6]=12.[C:17](Cl)(=[O:23])[O:18][CH2:19][CH2:20][O:21][CH3:22]>CCOC(C)=O>[Br:1][C:2]1[CH:3]=[N:4][N:5]2[CH:10]=[CH:9][C:8]([N:11]3[CH2:16][CH2:15][N:14]([C:17]([O:18][CH2:19][CH2:20][O:21][CH3:22])=[O:23])[CH2:13][CH2:12]3)=[N:7][C:6]=12Participants
Procedure
To 10.00 g (35.44 mmol) of 3-bromo-5-(piperazin-1-yl)pyrazolo[1,5-a]pyrimidine dissolved in 120 mL of EtOAc, at 0° C. was added 5.40 g (38.99 mmol) of 2-methoxyethyl carbonochloridate, followed by 9.86 mL (70.88 mmol) of TEA. After 5 minutes, the ice bath was removed, and the reaction mixture stirred at RT. After 5 hr, LCMS showed that the reaction was complete. It was diluted with EtOAc, quenched with brine, and the organic layer dried over MgSO4. It was concentrated and purified on the ISCO with a 330 g column eluting with 0-9% MeOH/DCM to obtain the desired product, 12.63 g (93%). 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 3.42 (s, 3 H) 3.62-3.69 (m, 6 H) 3.73-3.82 (m, 4 H) 4.26-4.35 (m, 2 H) 6.36 (d, J=7.83 Hz, 1 H) 7.86 (s, 1 H) 8.27 (d, J=7.83 Hz, 1 H). LRMS (ESI) m/e 384 [(M+H)+, (doublet), calcd for C14H15BrN5O3 383].
Workup
- customthe ice bath was removed
- waitAfter 5 hr
- additionIt was diluted with EtOAc
- customquenched with brine
- dry with materialthe organic layer dried over MgSO4
- concentrationIt was concentrated
- custompurified on the ISCO with a 330 g column
- washeluting with 0-9% MeOH/DCM
Sources & evidence
- ORD record
- ord-84fc7b520ef9448c8a7c38afd6696c43
- Source dataset
- uspto-grants-2015_02
- Patent number
- US08946415B2
Reaction notes
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