# US 11,897,843 B2 · Process for the preparation of enantiomerically enriched 3-aminopiperidine

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- Number: US 11,897,843 B2
- Document ID: US11897843B2
- Status: Granted
- Kind: B2
- Application number: 17/941,959
- Filed: 2022-09-09
- Published: 2023-01-12
- Granted: 2024-02-13
- Earliest claimed: 2013-02-20
- Assignees: Reuter Chemische Apparatebau KG
- Applicants: Reuter Chemische Apparatebau KG
- Inventors: Karl Reuter; Tobias Wedel; Viktor Meier; Mark Kantor; Vasyl Andrushko; Florian Stolz
- Web page: https://patentgrep.com/patent/US11897843B2

## CPC

- C07D 211/56: Nitrogen atoms (nitro radicals C07D211/38)
- 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
- C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08)

## Abstract

The present invention relates to a process for the preparation of enantiomerically enriched 3-aminopiperidine, as in particular of its R-enantiomer (R)-3-aminopiperidine. The invention also relates to an enantiomerically enriched intermediate of said process and to specific acid-addition salts of 3-aminopiperidine (hereinafter also APIP) that are useful for obtaining a single enantiomer of APIP, and to crystalline (R)-3-aminopiperidine-dihydrochloride-monohydrate and crystalline (S)-3-aminopiperidine-dihydrochloride-monohydrate.

## Claims

### Claim 1

Crystalline (R)-3-aminopiperidine-dihydrochloride-monohydrate.

### Claim 2

Crystalline (S)-3-aminopiperidine-dihydrochloride-monohydrate.

### Claim 3 (depends on 1)

The crystalline 3-aminopiperidine-dihydrochloride-monohydrate of claim 1, which in an X-ray powder diffraction diagram at 22° C. and Cu—Kα radiation displays at least 5 of the following reflections, quoted as 2θ values, selected from: 11.0±0.2°, 16.4±0.2°, 17.0±0.2°, 20.9±0.2°, 24.5±0.2°, 25.3±0.2°, 25.9±0.2°, 26.7±0.2°, 27.3±0.2°, 28.4±0.2°, 29.3±0.2°, 30.0±0.2°, 30.7±0.2°, 31.0±0.2° and 31.8±0.2°.

### Claim 4 (depends on 2)

The crystalline 3-aminopiperidine-dihydrochloride-monohydrate of claim 2, which in an X-ray powder diffraction diagram at 22° C. and Cu—Kα radiation displays at least 5 of the following reflections, quoted as 2θ values, selected from: 11.0 0.2°, 16.4±0.2°, 17.0±0.2°, 20.9±0.2°, 24.5±0.2°, 25.3±0.2°, 25.9±0.2°, 26.7±0.2°, 27.3±0.2°, 28.4±0.2°, 29.3±0.2°, 30.0±0.2°, 30.7±0.2°, 31.0±0.2° and 31.8±0.2°.