Pyrazolidine dihydrochloride → 2-(2-chlorobenzyl)-3-(2-methylsulfanyl-pyrimidin-4-yl)-6,7-dihydro-5H-pyrazolo[1,2-a]pyrazol-1-one

HRID 1455243Notes

Reaction equation

HRID 1455243 reaction equation
C(O[C:6](=[O:26])[CH:7]([CH2:18][C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][C:20]=1[Cl:25])[C:8]([C:10]1[CH:15]=[CH:14][N:13]=[C:12]([S:16][CH3:17])[N:11]=1)=O)(C)(C)C.Cl.Cl.[NH:29]1[CH2:33][CH2:32][CH2:31][NH:30]1>N1C=CC=CC=1>[Cl:25][C:20]1[CH:21]=[CH:22][CH:23]=[CH:24][C:19]=1[CH2:18][C:7]1[C:6](=[O:26])[N:30]2[CH2:31][CH2:32][CH2:33][N:29]2[C:8]=1[C:10]1[CH:15]=[CH:14][N:13]=[C:12]([S:16][CH3:17])[N:11]=1

Participants

4

Reactant 2

HCID 12314782Pyrazolidine dihydrochlorideHCID 574380732-(2-Chlorobenzyl)-3-(2-methylsulfanyl-pyrimidin-4-yl)-3-oxo-propionic acid tert-butyl ester2×

Product 1

HCID 574380712-(2-chlorobenzyl)-3-(2-methylsulfanyl-pyrimidin-4-yl)-6,7-dihydro-5H-pyrazolo[1,2-a]pyrazol-1-oneYield 22%

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Procedure

To a solution of 2-(2-chlorobenzyl)-3-(2-methylsulfanyl-pyrimidin-4-yl)-3-oxo-propionic acid tert-butyl ester, 6 (2.0 g, 5.7 mmol)) in pyridine (40 mL) is added pyrazolidine-bishydrochloride (1.2 g, 8.1 mmol). After stirring the reaction for 10 min at room temperature, the mixture i stirred at 90° C. for 2.5 hours and then at 60° C. for 17 hours. The solution i concentrated in vacuo and the resulting curd product is purified over silica (EtOAc followed by 20% MeOH/EtOAc) to afford 460 mg (22%) of the desired product: 1H NMR (300 MHz, CDCl3) δ 8.58 (d, J=5.1 Hz, 1H), 7.42-7.2 (m, 4H), 6.96 (d, J=5.1 Hz, 1H), 4.42-4.3 (m, 4H), 4.10 (s, 2H), 2.95-2.75 (m, 2H), 2.58 (s, 3H); ESI+ MS: m/z (rel intensity) 373.0 (100, M++H).

Workup

  1. customthe reaction for 10 min at room temperature
  2. stirringthe mixture i stirred at 90° C. for 2.5 hours
  3. concentrationThe solution i concentrated in vacuo
  4. customthe resulting curd product is purified over silica (EtOAc followed by 20% MeOH/EtOAc)

Sources & evidence

ORD record
ord-bce63c3284d04f468a24492c4b039f02
Source dataset
uspto-grants-2009_01
Patent number
US07482356B2

Reaction notes

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