Endo-benzonorbornen-2-ol as an efficient non-natural chiral auxiliary in the asymmetric aza-Diels-Alder reactions between cyclopentadiene and (1-phenylethyl)iminoacetates

• Type: Article in International Scientific Journal
• Date: 2014

Authors

Carlos A D Sousa (Author) Other; Miguel A Maestro (Author) Other; Xerardo Garcia Mera (Author) Other; Jose E Rodriguez Borges (Author) FCUP

Journal

Title: RSC Advances

Vol. 4

Pages: 57768-57772

ISSN: 2046-2069

Publisher: Royal Society of Chemistry

Indexing

ISI Web of Knowledge - 5 Citations

Scopus - 5 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-009-YTD

DOI: 10.1039/c4ra11143e

Abstract (EN): Exo-2-azabicyclo[2.2.1]hept-5-enes were obtained by cycloaddition reactions between cyclopentadiene and protonated (S)- and (R)-1-phenylethylimines of (1R, endo)- benzonorbornen-2-yl glyoxylate. The non-natural (1R, endo)- benzonorbornen-2-ol proved to be an efficient chiral auxiliary in these asymmetric aza-Diels-Alder reactions, which afforded only exo-cycloadducts with 1S : 1R diastereomeric ratios of 15 : 85 for (S)-(1-phenylethyl) imine and 93 : 7 for (R)-(1-phenylethyl) imine. The obtained diastereoisomers were effortlessly and efficiently isolated using a chromatographic column. The absolute configuration of all the formed adducts was unequivocally assigned through NMR, specific optical rotation and X-ray data.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 5