# US 5,708,176 A · Preparation of 3,5-lutidene

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 5,708,176 A
- Document ID: US5708176A
- Status: Granted
- Kind: A
- Application number: 08/725,434
- Filed: 1996-10-03
- Granted: 1998-01-13
- Earliest claimed: 1996-10-03
- Assignees: E. I. Du Pont de Nemours and Company
- Inventors: Ronald Lee Amey
- Web page: https://patentgrep.com/patent/US5708176A

## CPC

- C07D 213/08: Preparation by ring-closure
- C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08)

## Abstract

The present invention is a process for the manufacture of 3,5-lutidine and 3-picoline from 2-methyl-1,5-pentanediamine by vapor phase reaction with hydrogen at about 400.degree.-500.degree. C. over an oxide catalyst.

## Claims

### Claim 1

A process for the preparation of 3,5-lutidine and 3-picoline which comprises reacting in vapor phase 2-methyl-1,5-pentanediamine and hydrogen or hydrogen mixed with an inert gas over an oxide catalyst at temperatures from about 400.degree. to 500.degree. C. wherein the hydrogen or hydrogen mixed with the inert gas is present in a molar ratio from about 5/1 to 40/1 compared to the molar concentration of 2-methyl-1,5-pentanediamine and the oxide catalyst is selected from the group consisting of gamma-Al.sub.2 O.sub.3, gamma-Al.sub.2 O.sub.3 /SiO.sub.2, ZrO.sub.2 or mixtures thereof.

### Claim 2 (depends on 1)

The process according to claim 1 wherein the process is continuous and produces a product stream comprising the steps: (a) feeding hydrogen or hydrogen mixed with inert gases and volatilized 2-methyl-1,5-pentanediamine over an oxide catalyst at about 400.degree.-500.degree. C., (b) condensing liquid products from the product stream, and (c) recovering 3,5-lutidine and 3-picoline.

### Claim 3 (depends on 2)

The process of claim 2 where distillation is used to separate and recover 3,5-lutidine and 3-picoline.

### Claim 4 (depends on 3)

The process of claim 3 where the oxide catalyst is chosen from the group consisting of gamma-Al.sub.2 O.sub.3, gamma-Al.sub.2 O.sub.3 /SiO.sub.2, ZrO.sub.2 or mixtures thereof.

### Claim 5 (depends on 3)

The process of claim 3 where the oxide catalyst is gamma-Al.sub.2 O.sub.3 or gamma-Al.sub.2 O.sub.3 /SiO.sub.2.