2-Methyl-3-butyn-2-ol → 2-{3-Methyl-3-hydroxybutynyl}-5-{2-(4-pyridyl)ethynyl}thiophene

HRID 234043

Reaction equation

HRID 234043 reaction equation
[CH3:1][C:2]([OH:6])([C:4]#[CH:5])[CH3:3].Br[C:8]1[S:9][C:10]([C:13]#[C:14][C:15]2[CH:20]=[CH:19][N:18]=[CH:17][CH:16]=2)=[CH:11][CH:12]=1>[Pd]>[CH3:1][C:2]([OH:6])([CH3:3])[C:4]#[C:5][C:8]1[S:9][C:10]([C:13]#[C:14][C:15]2[CH:16]=[CH:17][N:18]=[CH:19][CH:20]=2)=[CH:11][CH:12]=1

Participants

4

Reactant 2

HCID 82582-Methyl-3-butyn-2-olHCID 23358156HCID 23358156, compound

Product 1

HCID 233581552-{3-Methyl-3-hydroxybutynyl}-5-{2-(4-pyridyl)ethynyl}thiophene

Reagents, catalysts & solvents 1

HCID 23938PalladiumCatalyst

Procedure

The 2-ethynyl-5-(4-pyridyl)ethynyl thiophene is synthesized by the reaction sequence shown below. In the first step, bromination of 1-(2-thienyl)-2-(4-pyridyl)ethene followed by base-catalyzed dehydrohalogenation gives 2-bromo-5-{2-(4-pyridyl)ethynyl}thiophene (I): ##STR5## In the second step, the palladium catalyzed addition of 2-methyl-3-butyn-2-ol to compound I gives 2-{3-methyl-3-hydroxybutynyl}-5-{2-(4-pyridyl)ethynyl}thiophene (II): ##STR6## The term "Ph" in the palladium catalyst formula means "phenyl". In the third step, removal of the protecting group using KOH in methanol gives the acetylene-terminated thermoset monomer 2-ethynyl-5-(4-pyridyl)ethynyl thiophene (III): ##STR7##

Sources & evidence

ORD record
ord-4959446866f7454595d5b68041b5c339
Source dataset
uspto-grants-1997_01
Patent number
US05594075

Linked notes

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