Sodium borohydride → HCID 19387095, compound

HRID 1655371Notes

Reaction equation

HRID 1655371 reaction equation
[N+:1]([C:4]1[CH:5]=[CH:6][C:7]2[O:12][C:11]([CH3:14])([CH3:13])[CH:10]([CH3:15])[C:9](=[O:16])[C:8]=2[CH:17]=1)([O-:3])=[O:2].[BH4-].[Na+]>CO>[N+:1]([C:4]1[CH:5]=[CH:6][C:7]2[O:12][C:11]([CH3:14])([CH3:13])[CH:10]([CH3:15])[CH:9]([OH:16])[C:8]=2[CH:17]=1)([O-:3])=[O:2]

Participants

4

Reactant 2

HCID 4311764Sodium borohydrideHCID 193871946-nitro-2,2,3-trimethyl-3,4-dihydro-2H-1-benzopyran-4-one

Product 1

HCID 19387095HCID 19387095, compoundYield 104.6%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A suspension of 6-nitro-2,2,3-trimethyl-3,4-dihydro-2H-1-benzopyran-4-one (40 g, 0.170 mol) in methanol (400 ml) was treated with sodium borohydride (6.4 g, 0.170 mol) at room temperature. After stirring for two hours the solvent was evaporated under reduced pressure, and the residue treated with a mixture of water and dichloromethane. After stirring the organic phase was separated and evaporated under reduced pressure to give 42.2 g of 6-nitro-2,2,3-trimethyl-4-hydroxy-3,4-dihydro-2H-1-benzopyran, as an oil, 1H NMR (CDCl3): δ 1.05 (d, 3H), 1.4 (s, 3H), 1.45 (s, 3H), 2.0-2.2 (m, 2H), 4.4 and 4.9 (multiplets cis and trans, 1H), 6.85 (m, 1H), 8.05 (m, 1H), 8.4 (m, 1H).

Workup

  1. customwas evaporated under reduced pressure
  2. additionthe residue treated with a mixture of water and dichloromethane
  3. stirringAfter stirring the organic phase
  4. customwas separated
  5. customevaporated under reduced pressure

Sources & evidence

ORD record
ord-df03988c0cf74b1fb7cedb3f0eb38e20
Source dataset
uspto-grants-1993_10
Patent number
US05250547

Reaction notes

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