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Inside Cover: Highly Stereoselective β‐Mannopyranosylation via the 1‐α‐Glycosyloxy‐isochromenylium‐4‐gold(I) Intermediates (Chem. Eur. J. 24/2015)
Author(s) -
Zhu Yugen,
Yu Biao
Publication year - 2015
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Reports
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201590103
Subject(s) - stereoselectivity , proton , chemistry , alcohol , catalysis , cover (algebra) , ion , stereochemistry , medicinal chemistry , organic chemistry , physics , nuclear physics , mechanical engineering , engineering
With the non‐coordinating (3,5‐bis‐CF 3 ‐Ph) 4 B − as a counter anion (the green X − in the picture), activation of a α‐mannopyranosyl ortho ‐alkynylbenzoate with a gold(I) species (the golden LAu + ) leads to a 1‐α‐mannosyloxy‐isochromenylium‐4‐gold(I) complex, which upon treatment with an alcohol stereoselectively affords the important but difficult‐to‐synthesize β‐mannopyranoside. Replacement of the LAu + from the isochromen‐4‐yl‐gold(I) species by a proton (the red H + ) originating from the alcohol completes the gold(I)‐catalytic cycle. For a comprehensive study see the Full Paper by B. Yu and Y. Zhu on page 8771 ff.