# US 5,344,939 A · Process for forming a fluoromethyl ketone

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- Number: US 5,344,939 A
- Document ID: US5344939A
- Status: Granted
- Kind: A
- Application number: 08/029,894
- Filed: 1993-03-11
- Granted: 1994-09-06
- Earliest claimed: 1990-02-16
- Assignees: Prototek, Inc.
- Inventors: James T. Palmer
- Web page: https://patentgrep.com/patent/US5344939A

## CPC

- C07D 207/08: with hydrocarbon radicals, substituted by hetero atoms, attached to ring carbon atoms
- C07C 45/676: {by elimination of carboxyl groups}
- C07C 67/343: by increase in the number of carbon atoms
- C07C 69/63: of saturated acids
- C07C 271/18: to carbon atoms of hydrocarbon radicals substituted by doubly-bound oxygen atoms
- C07C 271/20: to carbon atoms of hydrocarbon radicals substituted by nitrogen atoms not being part of nitro or nitroso groups
- C07C 271/22: to carbon atoms of hydrocarbon radicals substituted by carboxyl groups
- C07C 279/14: being further substituted by carboxyl groups
- C07C 303/26: of esters of sulfonic acids
- C07C 327/22: having carbon atoms of esterified thiocarboxyl groups bound to hydrogen atoms or to acyclic carbon atoms
- C07D 207/273: with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to other ring carbon atoms
- C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08)
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS

## Abstract

The preparation of magnesium benzyl fluoromalonate and other equivalent materials, the synthetic equivalents of the --CH.sub.2 F moiety, is described. Reaction between these reagents and the in situ-formed imidazolides of various carboxylic acids gives beta-keto-alpha-fluoroesters, which upon hydrogenation and spontaneous decarboxylation yields fluoromethyl ketones in excellent yields. The overall transformation from RCOOH to RCOCH.sub.2 F is thus illustrated.

## Claims

### Claim 1

A method for forming a beta-keto-alpha-fluoroester of a carboxylic acid which comprises the steps of
a. converting the carboxylic acid to give the corresponding imidazolide, and
b. reacting the imidazolide with a magnesium fluoromalonate of the formula ##STR21## wherein X is --O-- or --S--, and
R' is a hydrogenatively cleavable group.

### Claim 2 (depends on 1)

The method of claim 1 wherein in step (b) the magnesium fluoromalonate is such that X is --O-- and R' is selected from benzyl and substituted benzyl.

### Claim 3 (depends on 1)

The method of claim 1 wherein in step (b) the magnesium fluoromalonate has the formula ##STR22##

### Claim 4 (depends on 1)

The method of claim 1 wherein in step (b) the magnesium fluoromalonate has the formula ##STR23##