Process for the recovery of a boronic acid

Patent metadata

Field	Value
Publication number	US-10377700-B2
Application number	US-201815912772-A
Country	US
Kind code	B2
Filing date	Mar 6, 2018
Priority date	Nov 5, 2013
Publication date	Aug 13, 2019
Grant date	Aug 13, 2019

Abstract

The present invention discloses a process for recovery of a boronic acid of formula R3—B(OH)2, wherein R3 is selected from the group consisting of C1-C6 linear or branched alkyl, C3-C6 cycloalkyl, and C6 aryl, optionally substituted with a group selected from the group consisting of methyl, ethyl, n-propyl, i-propyl, n-butyl, sec-butyl, t-butyl, and phenyl, comprising admixing the boronic acid with a water-immiscible organic solvent in a weight ratio between the boronic acid and the water-immiscible organic solvent from 1:10 to 1:20, adding an aqueous solution to a final pH of neutral, and partitioning the boronic acid into an organic water-immiscible phase and recovery of the organic water-immiscible phase.

First claim

The invention claimed is:

1. A process for recovery of a boronic acid of formula R 3 —B(OH) 2 , wherein R 3 is selected from the group consisting of C 1 -C 6 linear or branched alkyl, C 3 -C 6 cycloalkyl, and C 6 aryl, optionally substituted with a group selected from the group consisting of methyl, ethyl, n-propyl, i-propyl, n-butyl, sec-butyl, t-butyl, and phenyl, from an aqueous mixture optionally comprising a polar solvent, said process comprising the following steps:
admixing an aqueous mixture comprising a boronic acid of formula R 3 —B(OH) 2 , wherein R 3 is as defined above, with a water-immiscible organic solvent in a weight ratio between the boronic acid and the water-immiscible organic solvent from 1:10 to 1:20, wherein the organic water-immiscible solvent is selected from the group consisting of 4-methyl-2-pentanone (MIBK), 3-pentanone, 2-pentanone, dibutyl ether, 2-methyl-tetrahydrofurane, cyclopentylmethyl ether, methyl isopropyl ketone, and methyl isopentyl ketone, and wherein the aqueous mixture optionally comprises a polar solvent,
adding an aqueous solution to a final pH from 6 to 7, and
partitioning the boronic acid into the organic water-immiscible phase and recovery of the organic water-immiscible phase.

2. The process according to claim 1 , wherein the boronic acid of Formula R 3 —B(OH) 2 is used for diol protection or is formed after hydrolysis of a diol protection group.

3. The process according to claim 1 , wherein the weight ratio between the boronic acid and the water-immiscible organic solvent is from 1:13 to 1:16 (w/w).

4. The process according to claim 1 , wherein R 3 is selected from the group consisting of methyl, butyl, and phenyl, optionally substituted with methyl.

5. The process according to claim 1 , wherein the process is carried out in a batch or in a continuous mode.

6. The process according to claim 1 , wherein the process is carried out in a batch mode.

7. The process according to claim 1 , wherein the process is carried out in a continuous mode.

Assignees

• Bracco Imaging Spa

Inventors

• Battistini Elisa
• Buonsanti Federica
• Imperio Daniela
• Lattuada Luciano
• Napolitano Roberta

Classifications

• C07C237/46

  having carbon atoms of carboxamide groups, amino groups and at least three atoms of bromine or iodine, bound to carbon atoms of the same non-condensed six-membered aromatic ring · CPC title

• C07C231/14 Primary

  by formation of carboxamide groups together with reactions not involving the carboxamide groups · CPC title

• C07F5/05

  Cyclic compounds having at least one ring containing boron but no carbon in the ring · CPC title

• Y02P20/55

  Design of synthesis routes, e.g. reducing the use of auxiliary or protecting groups · CPC title

• C07C227/04

  Formation of amino groups in compounds containing carboxyl groups · CPC title