Sodium borohydride → HCID 131736287, compound

HRID 1053696Notes

Reaction equation

HRID 1053696 reaction equation
[BH4-].[Na+].[H][H].[Si:5]([O:12][CH:13]([C:27]1[CH:32]=[C:31]([N+:33]([O-])=O)[CH:30]=[CH:29][C:28]=1[CH3:36])[CH:14]([CH2:23][N+:24]([O-])=O)[CH2:15][C:16]([O:18][C:19]([CH3:22])([CH3:21])[CH3:20])=[O:17])([C:8]([CH3:11])([CH3:10])[CH3:9])([CH3:7])[CH3:6]>CO.O.O.O.O.O.O.[Ni](Cl)Cl>[NH2:24][CH2:23][CH:14]([CH:13]([C:27]1[CH:32]=[C:31]([NH2:33])[CH:30]=[CH:29][C:28]=1[CH3:36])[O:12][Si:5]([C:8]([CH3:11])([CH3:10])[CH3:9])([CH3:7])[CH3:6])[CH2:15][C:16]([O:18][C:19]([CH3:22])([CH3:20])[CH3:21])=[O:17]

Participants

6

Reactant 3

HCID 4311764Sodium borohydride2×HCID 123530590HCID 123530590, compoundHCID 178418361HCID 178418361, compound

Product 1

HCID 131736287HCID 131736287, compound

Reagents, catalysts & solvents 2

HCID 11791229Dichloronickel;hexahydrateCatalystHCID 887MethanolSolvent2×

Procedure

Adapting literature known protocols (Osby and Ganem, Tetrahedron Lett., 1985, 26(52), 6413-6416), a mixture of nickel(II) dichloride hexahydrate (NiCl2.6H2O) (1.19 g, 5.0 mmol) in methanol (MeOH) (80 mL) is sonicated to effect complete dissolution. Solid sodium borohydride (NaBH4) (567 mg, 15.0 mmol) is added in small portions upon a black precipitate (Ni2B) is generated immediately and hydrogen gas is generated (exotherm!). After about 30 min, a solution of tert-butyl 4-(tert-butyl(dimethyl)silyl)oxy-4-(2-methyl-5-nitro-phenyl)-3-(nitromethyl)butanoate (17c) (4.69 g, 10.0 mmol) in MeOH (20 mL) is added followed by portion-wise addition of more NaBH4 (1.13 g, 30.0 mmol) at room temperature. The reaction is monitored by TLC and/or LCMS till completion. The reaction mixture is filtered over Celite® 545 and the filter residue is washed with additional MeOH. The combined filtrates are evaporated to dryness under reduced pressure using a rotary evaporator. The crude tert-butyl 3-(aminomethyl)-4-(5-amino-2-methyl-phenyl)-4-(tert-butyl(dimethyl)silyl)oxy-butanoate (17d) is used directly in the next step without further isolation and purification procedures.

Workup

  1. customis sonicated
  2. dissolutiondissolution
  3. filtrationThe reaction mixture is filtered over Celite® 545
  4. washthe filter residue is washed with additional MeOH
  5. customThe combined filtrates are evaporated to dryness under reduced pressure
  6. customa rotary evaporator
  7. customThe crude tert-butyl 3-(aminomethyl)-4-(5-amino-2-methyl-phenyl)-4-(tert-butyl(dimethyl)silyl)oxy-butanoate (17d) is used directly in the next step without further isolation and purification procedures

Sources & evidence

ORD record
ord-7119a3c0bb824c73945a6e8b813b5d65
Source dataset
uspto-grants-2016_07
Patent number
US09394236B2

Reaction notes

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