Hydrazine hydrate (1:1) → 4-p-tolylmethanesulfonyl-2H-pyrazol-3-ylamine

HRID 63767Notes

Reaction equation

HRID 63767 reaction equation
C(N1C(C2C=CC=CC=2)CC(C)(C)[N:10]2[N:22]=CC(C(=O)CC3C=CC(C)=CC=3)=C12)C1C=CC=CC=1.C(O[CH:38]=[C:39]([S:42]([CH2:45][C:46]1[CH:51]=[CH:50][C:49]([CH3:52])=[CH:48][CH:47]=1)(=[O:44])=[O:43])[C:40]#[N:41])C.O.NN>C(O)C>[C:49]1([CH3:52])[CH:50]=[CH:51][C:46]([CH2:45][S:42]([C:39]2[CH:38]=[N:22][NH:10][C:40]=2[NH2:41])(=[O:44])=[O:43])=[CH:47][CH:48]=1

Participants

5

Reactant 3

HCID 24654Hydrazine hydrate (1:1)HCID 576320601-(4-Benzyl-7,7-dimethyl-5-phenyl-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)-2-(4-methylphenyl)ethanoneHCID 68864576HCID 68864576, compound

Product 1

HCID 688654214-p-tolylmethanesulfonyl-2H-pyrazol-3-ylamine

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

7,7-Dimethyl-3-(4-methylbenzyl)sulfonyl)-5-phenyl-4,7-dihydropyrazolo[1,5-a]pyrimidine (4): A slurry of 1.9 g (7.2 mmol) of 3 in 25 mL of ethanol was treated with 0.38 mL (7.9 mmol) of hydrazine monohydrate and heated to reflux for 3 h. The reaction was concentrated in vacuo to give crude 4-p-tolylmethanesulfonyl-2H-pyrazol-3-ylamine as a tan solid. The crude pyrazole, 1.3 g (7.9 mmol) of 3-methyl-1-phenyl-but-2-en-1-one and 2.8 mL (36 mmol) of trifluoroacetic acid was dissolved in 25 mL of 2-methoxyethanol and heated to reflux for 3 days. The reaction was then cooled to room temperature, concentrated in vacuo and dissolved in AcOEt. This solution was washed successively with saturated sodium bicarbonate, water and brine before being dried over sodium sulfate. The solution was filtered, concentrated in vacuo and the resulting crude material was purified by flash chromatography eluting with a 75 to 33% hexanes/AcOEt gradient to give 1.25 g (44%) of the title compound as a powder. 1H NMR (CDCl3) δ 1.67 (s, 6H), 2.13 (s, 3H), 4.26 (s, 2H), 4.81 (d, J=2.0 Hz, 1H), 6.39 (s, 1H), 7.05 (dd, J=8.0, 18.5 Hz, 4H), 7.20 (dd, J=3.7, 7.4 Hz, 2H), 7.36-7.39 (m, 3H), 7.52 (s, 1H). MS Calcd.: 393. Found: 394 (M+H).

Workup

  1. temperatureheated
  2. temperatureto reflux for 3 h
  3. concentrationThe reaction was concentrated in vacuo

Sources & evidence

ORD record
ord-261b25949b414c969ee5aff0651318b1
Source dataset
uspto-grants-2016_09
Patent number
US09447100B2

Reaction notes

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