# US 11,299,455 B2 · Process for diastereoselective synthesis of vicinal diamines

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

- Number: US 11,299,455 B2
- Document ID: US11299455B2
- Status: Granted
- Kind: B2
- Application number: 17/256,962
- Filed: 2019-07-11
- Published: 2022-03-10
- Granted: 2022-04-12
- Earliest claimed: 2018-07-12
- Assignees: Piramal Pharma Limited
- Applicants: Piramal Pharma Limited
- Inventors: Rajender Reddy Leleti; Sharadsrikar Kotturi; Kumara Swamy Nalivela; Chirag Patel; Poojabahen Raval; Vinkal Zalavadiya
- Web page: https://patentgrep.com/patent/US11299455B2

## CPC

- C07C 303/40: by reactions not involving the formation of sulfonamide groups
- C07C 313/06: Sulfinamides
- C07D 307/52: Radicals substituted by nitrogen atoms not forming part of a nitro radical
- C07D 333/22: Radicals substituted by doubly bound hetero atoms, or by two hetero atoms other than halogen singly bound to the same carbon atom
- C07B 2200/07: Optical isomers
- C07C 2601/14: The ring being saturated
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08)
- C07B: GENERAL METHODS OF ORGANIC CHEMISTRY; APPARATUS THEREFOR (preparation of carboxylic acid esters by telomerisation C07C67/47; telomerisation C08F)

## Abstract

The present invention relates to an improved process for diastereoselective synthesis of vicinal diamines (1). The process involves highly regio- and diastereoselective addition of 2-azaallyl anions (4) to N-tert-butanesulfinylimines (5) to produce vicinal diamines (1).

## Claims

### Claim 1

A process for the preparation of diastereoselective synthesis of vicinal diamines of compound of formula (1),
the process comprising:
(a) reacting a compound of formula (2) or a compound of formula (3) with a base in an organic solvent to produce 2-azaallyl anion of formula (4), which is optionally isolated; and
(b) condensing 2-azaallyl anion of formula (4) with a compound of formula (5) in a solvent to produce vicinal diamines of formula (1),
wherein, R and R1 is independently selected from H, C1-C10 linear or branched or cyclic alkyl, substituted or unsubstituted aryl, ester, ether, hetero aryl, halo, haloalkyl.

### Claim 2 (depends on 1)

The process according to claim 1, wherein solvent(s) used in step (a) and (b) is selected from an ether; alcohol; halogenated; ketone solvent; aprotic solvent such as acetonitrile, N,N-dimethyl formamide (DMF), N,N-dimethyl acetamide, dimethylsulfoxide (DMSO) and N-methylpyrrolidone (NMP); an aromatic solvent; water or a mixture thereof.

### Claim 3 (depends on 1)

The process according to claim 1, wherein in step (a) and step (b), the solvent is an ether solvent selected from the group consisting of tetrahydrofuran, cyclopentyl methyl ether, 2-methyltetrahydrofuran and diethyl ether.

### Claim 4 (depends on 1)

The process according to claim 1, wherein in step (a) the base is selected from potassium hydride (KH), potassium tert-butoxide (tert-BuOK), sodium amide (NaNH2), sodium hexamethyldisilazide (NaHMDS) or a lithium amide base.

### Claim 5 (depends on 1)

The process according to claim 1, wherein in step (a) the base is a lithium amide base selected from the group consisting of lithium diethylamide, lithium diisopropylamide (LDA), lithium pyrrolidinamide, lithium piperidinamide, lithium isopropylcyclohexylamide, lithium tetramethylpiperidide (LiTMP) and lithium hexamethyl disilazide (LiHMDS).

### Claim 6 (depends on 1)

The process according to claim 1, wherein step (a) is carried out at temperature in the range of −70° C. to −90° C.