4-Aminophenol → 4-Aminophenoxy-4'-phenylethynylbenzophenone

HRID 35986

Reaction equation

HRID 35986 reaction equation
[C:1]1([C:7]#[C:8][C:9]2[CH:23]=[CH:22][C:12]([C:13]([C:15]3[CH:20]=[CH:19][C:18](F)=[CH:17][CH:16]=3)=[O:14])=[CH:11][CH:10]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[NH2:24][C:25]1[CH:30]=[CH:29][C:28]([OH:31])=[CH:27][CH:26]=1.C(=O)([O-])[O-].[K+].[K+]>CN(C)C(=O)C>[NH2:24][C:25]1[CH:30]=[CH:29][C:28]([O:31][C:16]2[CH:17]=[CH:18][CH:19]=[CH:20][C:15]=2[C:13]([C:12]2[CH:22]=[CH:23][C:9]([C:8]#[C:7][C:1]3[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=3)=[CH:10][CH:11]=2)=[O:14])=[CH:27][CH:26]=1

Participants

5

Reactant 3

HCID 4034-AminophenolHCID 11430Potassium CarbonateHCID 40956574-Fluoro-4'-(phenylethynyl)benzophenone

Product 1

HCID 544968244-Aminophenoxy-4'-phenylethynylbenzophenone

Reagents, catalysts & solvents 1

HCID 31374DimethylacetamideSolvent

Procedure

The phenylethynyl group has two important advantages over the ethynyl group. These are stability towards conditions of aromatic nucleophilic displacement reactions and stability at moderate temperatures (i.e. 150-250° C.). For example, when 4-phenylethynyl-4'-fluorobenzophenone was treated with a slight excess of 3 or 4-aminophenol in the presence of an alkali metal base such as potassium carbonate in a polar aprotic solvent such as N,N-dimethylacetamide (DMAc) at 143° C., 3 or 4-aminophenoxy-4'-phenylethynylbenzophenone was afforded in nearly quantitative yield. However, several attempts to make the 3-aminophenoxy-4'-ethynylbenzophenone from the 4-ethynyl-4'-fluorobenzophenone under similar reaction conditions afforded a mixture of products. In addition, imide model compounds of the phenylethynyl endcapper react at a moderate to fast rate in air at 300° to 350° C. whereas analogous model compounds containing the ethynyl group react at a moderate to fast rate in air at 200° to 250° C. Phenylethynyl containing imide model compounds are reasonably stable at 200° C. (see Example 6) whereas thynyl containing imide model compounds react at 200° C.

Workup

  1. customat moderate temperatures (i.e. 150-250° C.)
  2. customat 143° C.

Sources & evidence

ORD record
ord-5264557d0e934eab82b17a6d29d127c5
Source dataset
uspto-grants-1995_05
Patent number
US05412066

Linked notes

Loading…