2-Methyl-3-butyn-2-ol → 3-Butyn-2-ol, 2-methyl-4-(3-nitrophenyl)-

HRID 1976337Notes

Reaction equation

HRID 1976337 reaction equation
[CH3:1][C:2]([OH:13])([C:4]#[C:5]C1C=CC=C(N)C=1)[CH3:3].NC#CC1C=CC=CC=1.NC1C=C(C#C)C=CC=1.Br[C:33]1[CH:34]=[C:35]([N+:39]([O-:41])=[O:40])[CH:36]=[CH:37][CH:38]=1.CC(O)(C#C)C.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>C(N(CC)CC)C.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1>[CH3:1][C:2]([OH:13])([C:4]#[C:5][C:33]1[CH:38]=[CH:37][CH:36]=[C:35]([N+:39]([O-:41])=[O:40])[CH:34]=1)[CH3:3]

Participants

9

Reactant 6

HCID 82582-Methyl-3-butyn-2-ol2×HCID 11457Benzene, 1-bromo-3-nitro-2×HCID 11776TriphenylphosphineHCID 104682Benzenamine, 3-ethynyl-HCID 1122363-Butyn-2-ol, 4-(3-aminophenyl)-2-methyl-HCID 12341474Phenylethyn-1-amine

Product 1

HCID 1184803-Butyn-2-ol, 2-methyl-4-(3-nitrophenyl)-

Reagents, catalysts & solvents 2

HCID 178418476HCID 178418476, compoundCatalystHCID 8471TriethylamineSolvent

Procedure

Sabourin, Prepr. Div. Pet. Chem., Am. Chem. Soc., vol. 24, pp. 233-239 discloses the preparation of 2-methyl-4-(3-aminophenyl)-3-butyn-2-ol (an aminophenylacetylene) and 3-aminophenylacetylene in two and three steps, respectively, from 3-bromonitrobenzene and 2-methyl-3-butyn-2-ol. In the first step, 3-bromonitrobenzene and 2-methyl-3-butyn-2-ol were reacted in the presence of a catalyst system of bis(triphenylphosphine)palladium dichloride, additional triphenylphosphine, and cuprous iodide in triethylamine solvent at the reflux temperature to obtain 2-methyl-4-(3-nitrophenyl)-3-butyn-2-ol. In the second step, this nitrophenylacetylene was hydrogenated in isopropanol in the presence of a Ru/Al2O3 catalyst to obtain 2-methyl-4-(3-aminophenyl)-3-butyn-2-ol. This reference states that is essential to stop the hydrogenation reaction at the stoichiometric point because reduction of the triple bond ensues. In the third step, this aminophenylacetylene was heated in toluene in the presence of sodium hydroxide pellets, with removal of the acetone co-product by distillation, to obtain 3-aminophenylacetylene.

Sources & evidence

ORD record
ord-84c39ce3df4b4635b6b4b4060582c263
Source dataset
uspto-grants-2001_05
Patent number
US06225499B1

Reaction notes

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