Methyl chloroglyoxylate → Methyl 2-(2-(3-chlorophenyl)-5-methyl-7-(p-tolyl)pyrazolo[1,5-a]pyrimidin-6-yl)-2-oxoacetate

HRID 472864Notes

Reaction equation

HRID 472864 reaction equation
Br[C:2]1[C:3]([CH3:19])=[N:4][C:5]2[N:6]([N:9]=[C:10]([C:12]3[CH:17]=[CH:16][CH:15]=[C:14]([Cl:18])[CH:13]=3)[CH:11]=2)[C:7]=1Cl.[C:20]1([CH3:28])[CH:25]=[CH:24][C:23]([Mg]Br)=[CH:22][CH:21]=1.C1COCC1.[Li+].[Cl-].C1COCC1.Cl[C:42](=[O:47])[C:43]([O:45][CH3:46])=[O:44]>C1COCC1.CCOCC.[Cu]Br>[Cl:18][C:14]1[CH:13]=[C:12]([C:10]2[CH:11]=[C:5]3[N:4]=[C:3]([CH3:19])[C:2]([C:42](=[O:47])[C:43]([O:45][CH3:46])=[O:44])=[C:7]([C:23]4[CH:24]=[CH:25][C:20]([CH3:28])=[CH:21][CH:22]=4)[N:6]3[N:9]=2)[CH:17]=[CH:16][CH:15]=1

Participants

8

Reactant 4

HCID 79846Methyl chloroglyoxylateHCID 68902752LiCl THFHCID 866702846-Bromo-7-chloro-2-(3-chlorophenyl)-5-methylpyrazolo[1,5-a]pyrimidineHCID 178420639HCID 178420639, compound

Product 1

HCID 66693787Methyl 2-(2-(3-chlorophenyl)-5-methyl-7-(p-tolyl)pyrazolo[1,5-a]pyrimidin-6-yl)-2-oxoacetateYield 24.6%

Reagents, catalysts & solvents 3

HCID 24593copper(I) bromideCatalystHCID 3283Diethyl EtherSolventHCID 8028TetrahydrofuranSolvent

Procedure

To a stirred mixture of 6-bromo-7-chloro-2-(3-chlorophenyl)-5-methylpyrazolo[1,5-a]pyrimidine (0.179 g, 0.5 mmol) and copper(I) bromide (0.036 g, 0.250 mmol) in THF (3 mL) was added dropwise over 10 min a pre-mixed solution of 1M p-tolylmagnesiumbromide/THF (3.00 ml, 3.00 mmol) and 0.5M LiCl/THF (6.00 ml, 3.00 mmol) at rt. After 2.5 h, methyl 2-chloro-2-oxoacetate (0.552 ml, 6 mmol) was added at once and stirred overnight at rt. Then, the reaction was diluted with Et2O (50 mL), quenched with Na2CO3 (1 mL), washed with 10 mL each water and brine, dried (Na2SO4), filtered and concentrated to give orange paste which was purified by prep-HPLC to afford methyl 2-(2-(3-chlorophenyl)-5-methyl-7-(p-tolyl)pyrazolo[1,5-a]pyrimidin-6-yl)-2-oxoacetate (0.103 g, 0.123 mmol, 24.53% yield) as yellow solid which is contaminated with impurity. 1H NMR (500 MHz, CDCl3) δ: 7.95 (d, J=0.9 Hz, 1H), 7.81 (td, J=4.4, 1.5 Hz, 1H), 7.62 (d, J=8.2 Hz, 2H), 7.40 (d, J=7.6 Hz, 2H), 7.38-7.36 (m, 2H), 6.99 (s, 1H), 3.39 (s, 3H), 2.71 (s, 3H), 2.71 (s, 3H). LCMS (M+H) calcd for C23H19ClFN3O3: 420.11. found: 420.2.

Workup

  1. customquenched with Na2CO3 (1 mL)
  2. washwashed with 10 mL each water and brine
  3. dry with materialdried (Na2SO4)
  4. filtrationfiltered
  5. concentrationconcentrated
  6. customto give orange paste which
  7. customwas purified by prep-HPLC

Sources & evidence

ORD record
ord-b333f77b9abd438bb5ea5ab046f04eff
Source dataset
uspto-grants-2014_01
Patent number
US08633200B2

Reaction notes

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