Accelerated and enantioselective synthesis of a library of p-stereogenic urea phosphines

TitleAccelerated and enantioselective synthesis of a library of p-stereogenic urea phosphines
Publication TypeJournal Article
Year of Publication2018
AuthorsKoshti, VS, Gote, RP, Chikkali, SH
JournalEuropean Journal Of Organic Chemistry
Issue47
Pagination6768-6779
Date PublishedDEC
Type of ArticleArticle
ISSN 1434-193X
Abstract

Chiral phosphorus ligands play a central role in majority of the asymmetric transformations. However, access to chiral phosphorus ligands is limited due to their challenging synthesis. Reported here is a highly efficient and accelerated catalytic asymmetric synthesis of P-stereogenic urea containing phosphines leading to a small library of 18 chiral phosphorus compounds. Characteristic two doublets in a P-31 NMR spectrum, spectroscopic and analytical evidences authenticated the formation of [Pd-{(S,S) Me-FerroLANE}(m-phenylurea)(I)] complex. Indeed, [Pd-{(S,S) Me-FerroLANE}(m-phenylurea)(I)] was found to catalyze the C-P coupling reaction and quantitative conversion was observed within 18 hours. Under optimized conditions, iodophenyl urea's (2a-2j) were treated with secondary phosphines (1a-1c) in presence of [Pd-{(S,S) Me-FerroLANE}(m-phenylurea)(I)] to obtain P-stereogenic urea phosphines 5a-5r. The identity of these urea derived phosphines was unambiguously ascertained using a combination of spectroscopic and analytical methods. The catalyst tolerated various functional groups and yielded corresponding urea containing phosphines with an enantiomeric excess in the range of 15-62 %.

DOI10.1002/ejoc.201801309
Type of Journal (Indian or Foreign)

Foreign

Impact Factor (IF)

2.882

Divison category: 
Polymer Science & Engineering