Browse Prior Art Database

PROCESS FOR THE PREPARATION OF 4H-PYRAN-4-ONE DERIVATIVES

IP.com Disclosure Number: IPCOM000235923D
Publication Date: 2014-Mar-30
Document File: 2 page(s) / 201K

Publishing Venue

The IP.com Prior Art Database

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 51% of the total text.

Page 01 of 2

PROCESS FOR THE PREPARATION OF 4H-PYRAN-4-ONE DERIVATIVES

    Disclosed herein after is a process for the preparation of 4H-Pyran-4-one derivatives (compound 1a). Compound 1a having the following chemical structure:

;

Wherein:

R1 can be: alkyl (a part of an alkyl ester group).

R2 can be: alkyl (a part of an ether group), CH2-aryl, C(O)-alkyl (a part of an alkyl ester group), C(O)NH2 (a part of a carbamate group), C(O)NH-alkyl (a part of an alkyl carbamate group), C(O)N-(alkyl)2, C(O)O-alkyl (a part of an alkyl carbonate group)

R3 can be: NH2 (a part of an amide group), optionally substituted: NH-alkyl, NH-aryl, NH-alkylaryl (a part of an alkyl amide group), N-(alkyl)2, N-alkyl-N-aryl (a part of dialkyl amide group).

The following examples describes the preparation of methyl 3-(benzyloxy)-5-((2,4- difluorobenzyl)-carbamoyl)-4-oxo-4H-pyran-2-carboxylate (compound I), an example for compound 1a derivative.

Examples:

Example 1: Preparation of 4-(benzyloxy)-N-(2,4-difluorobenzyl)-3-oxobutanamide (Compound II)

To a solution of ethyl 4-(benzyloxy)-3-oxobutanoate (1 eq) in Toluene (3 vol) Sodium methoxide (0.1 eq) and 2,4-difluorobenzyl amine (1.3 eq) is added. The reaction mixture is stirred at 85°C overnight. The mixture is cooled to room temperature and washed with 10% HCl solution, 10% sodium carbonate and water. The organic phase is dried and concentrated under reduced pressure to give the desired product.


Page 02 of 2

Example 2: Preparation of 4-(benzyloxy)-N-(2,4-difluorobenzyl)-2- (dimethylamino)methylene)-3-oxobutanamide (Compound III)

To a solution of compound II (1 eq) in THF (2 vol) N...