Linked Life Data

11777432

Source:http://linkedlifedata.com/resource/pubmed/id/11777432

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2002-1-4
pubmed:abstractText
Boronic acid-containing molecules are employed in a broad range of biological, medicinal, and synthetic applications. These compounds, however, tend to be difficult to handle by solution-phase methods. Herein, this problem is addressed with the development of the first general solid-phase approach for the derivatization of functionalized boronic acids. This approach is based on the use of a diethanolamine resin anchor that facilitates boronic acid immobilization by avoiding the need for exhaustive removal of water in the esterification process. The immobilization of a wide variety of boronic acids onto N,N-diethanolaminomethyl polystyrene (DEAM-PS, 1) can be performed within minutes by simple stirring in anhydrous solvents at room temperature. Evidence for the formation of a bicyclic diethanolamine boronate with putative N-B coordination was shown by (1)H NMR analysis of DEAM-PS-supported p-tolylboronic acid. The hydrolytic cleavage of the same model boronic acid from the DEAM-PS resin was studied by UV spectroscopy. Hydrolysis and attachment were shown to occur under a rapidly attained equilibrium, and a large excess of water (>32 equiv) is required to effect a practically quantitative release of boronic acids from DEAM-PS. Despite their relative sensitivity to water and alcohols, DEAM-PS-bound arylboronic acids functionalized with a formyl, a bromomethyl, a carboxyl, or an amino group can be transformed in good to excellent yields into a wide variety of amines, amides, anilides, and ureas, respectively. Ugi multicomponent reactions on DEAM-PS-supported aminobenzeneboronic acids, derivatization of multifunctional arylboronic acids, and sequential reactions can also be carried out efficiently. These new DEAM-PS-supported arylboronic acids can be employed directly into resin-to-resin transfer reactions (RRTR). This type of multiresin process helps eliminate time-consuming cleavage and transfer operations, thereby considerably simplifying the outlook of combinatorial library synthesis by manual or automated means. This concept was illustrated by a set of optimized procedures for the Suzuki cross-coupling and the borono-Mannich reactions.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-3263
pubmed:author
pubmed:issnType
Print
pubmed:day
11
pubmed:volume
67
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3-15
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Universal solid-phase approach for the immobilization, derivatization, and resin-to-resin transfer reactions of boronic acids.
pubmed:affiliation
Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't