# US 10,370,330 B2 · Method for producing 5-hydroxypiperidine-2-carboxylic acid

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- Number: US 10,370,330 B2
- Document ID: US10370330B2
- Status: Granted
- Kind: B2
- Application number: 15/965,316
- Filed: 2018-04-27
- Published: 2018-08-30
- Granted: 2019-08-06
- Earliest claimed: 2013-12-27
- Assignees: Api Corporation
- Applicants: Api Corporation
- Inventors: Jun Takehara; Masato Murai; Takashi Ohtani; Tomoko Maeda; Tsugihiko Hidaka
- Web page: https://patentgrep.com/patent/US10370330B2

## CPC

- C07D 211/60: Carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals
- C07C 233/47: having the carbon atom of the carboxamide group bound to a hydrogen atom or to a carbon atom of an acyclic saturated carbon skeleton
- C07C 309/66: Methanesulfonates
- C07D 498/08: Bridged systems
- Y02P 20/55: Design of synthesis routes, e.g. reducing the use of auxiliary or protecting groups
- C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08)
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

A method for producing (2S,5S)/(2R,5R)-5-hydroxypiperidine-2-carboxylic acid represented by the formula (10) below: the method comprising the step of removing the protecting group from the hydroxyl group in a compound represented by the formula (7) below: (wherein P represents a protecting group, R3 represents an alkyl group containing 1 to 4 carbon atoms, and A represents an alkyl group containing 1 to 10 carbon atoms, an aryl group containing 6 to 12 carbon atoms, an alkyloxy group containing 1 to 4 carbon atoms, or an aralkyloxy group containing 7 to 20 carbon atoms) to synthesize a compound represented by the formula (8) below: (wherein R3 represents an alkyl group containing 1 to 4 carbon atoms, and A represents an alkyl group containing 1 to 10 carbon atoms, an aryl group containing 6 to 12 carbon atoms, an alkyloxy group containing 1 to 4 carbon atoms, or an aralkyloxy group containing 7 to 20 carbon atoms).

## Claims

### Claim 1

A method for producing (2S,5S)/(2R,5R)-5-hydroxypiperidine-2-carboxylic acid represented by the formula (10) below:
the method comprising (i) the step of:
(a) hydrolyzing the ester groups of the compound (8) below:
wherein R3 represents an alkyl group containing 1 to 4 carbon atoms, and A represents an alkyl group containing 1 to 10 carbon atoms, an aryl group containing 6 to 12 carbon atoms, an alkyloxy group containing 1 to 4 carbon atoms, or an aralkyloxy group containing 7 to 20 carbon atoms,
and allowing one of the carboxyl groups to react with the hydroxyl group to allow the lactonization, and further decarboxylating the other carboxyl group; or
(b) hydrolyzing the ester groups of the compound (8), decarboxylating one of the carboxyl groups to form a stereoisomeric mixture of a 2-monocarboxylic acid, and then isomerizing and lactonizing the stereoisomeric mixture;
to synthesize a compound represented by the formula (9) below:
wherein A represents an alkyl group containing 1 to 10 carbon atoms, an aryl group containing 6 to 12 carbon atoms, an alkyloxy group containing 1 to 4 carbon atoms, or an aralkyloxy group containing 7 to 20 carbon atoms.

### Claim 2 (depends on 1)

The method for producing (2S,5S)/(2R,5R)-5-hydroxypiperidine-2-carboxylic acid according to claim 1, further comprising (ii) the step of:
cleaving the amide bond in the compound (9) and hydrolyzing the lactone in the compound (9) to synthesize (2S,5S)/(2R,5R)-5-hydroxypiperidine-2-carboxylic acid.