Hydrazine → 3-Chloro-6-hydrazinyl-4-(trimethylsilyl)pyridazine

HRID 1887031Notes

Reaction equation

HRID 1887031 reaction equation
[Cl:1][C:2]1[N:3]=[N:4][C:5](Cl)=[CH:6][C:7]=1[Si:8]([CH3:11])([CH3:10])[CH3:9].[NH2:13][NH2:14].C(N(C(C)C)CC)(C)C>>[Cl:1][C:2]1[N:3]=[N:4][C:5]([NH:13][NH2:14])=[CH:6][C:7]=1[Si:8]([CH3:11])([CH3:10])[CH3:9]

Participants

4

Conditions

Temperature
72.5 °C

Procedure

A round-bottom flask under N2 was charged with 20 (13.6 g, 61.4 mmol) and anhydrous hydrazine (1M in THF, 184 mL, 184 mmol) followed by diisopropylethyl amine (11 mL, 61.4 mmol). The reaction was heated to a gentle reflux (70-75° C., external temperature) monitoring the reaction by LCMS. After 4 days the dark mixture was cooled, silica gel (20 g) was added and the mixture was concentrated. The crude mixture was combined with the crude material from a second reaction (16 mmol) and purified on a silica column (120 g, 0-5% MeOH/dichloromethane) to provide 7.5 g (45%) of 21 as a reddish oil/solid mix. Some trace impurities and residual diisopropylethyl amine remained. The product was used ‘as is’ in the next step.

Workup

  1. temperatureThe reaction was heated to
  2. customthe reaction by LCMS
  3. temperatureAfter 4 days the dark mixture was cooled
  4. additionsilica gel (20 g) was added
  5. concentrationthe mixture was concentrated
  6. customThe crude mixture was combined with the crude material from a second reaction (16 mmol)
  7. custompurified on a silica column (120 g, 0-5% MeOH/dichloromethane)

Sources & evidence

ORD record
ord-c090f962a3bd41388cf11071a18a1278
Source dataset
uspto-grants-2013_08
Patent number
US08501738B2

Reaction notes

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