Premium
Highly Regioselective Monoacylation of Unprotected Glucopyranoside Using Transient Directing‐Protecting Groups
Author(s) -
Rocheleau Sylvain,
Pottel Joshua,
Huskić Igor,
Moitessier Nicolas
Publication year - 2017
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.201601457
Subject(s) - regioselectivity , chemistry , monosaccharide , intramolecular force , surface modification , combinatorial chemistry , organic chemistry , protecting group , catalysis , alkyl
The regioselective functionalization of monosaccharides is notoriously achieved using metal catalysis, lengthy synthetic strategies requiring protection/deprotection, various enzymes, or other methods that target cis ‐diols (and thus cannot be used with glucopyranose derivatives), In this paper, we report a new method using selected boronic acids as temporary protecting groups, and describe its application to the regioselective functionalization of methyl α‐ d ‐glucopyranoside, the most difficult monosaccharide to functionalize regioselectively. Generally, reactions of glucopyranosides may lead to a plethora of mono‐ and polyfunctionalized derivatives, yet our method gave the 3‐ O ‐acetylated, 2‐ O ‐benzoylated, and 2‐ O ‐pivaloylated derivatives of methyl α‐ d ‐glucopyranoside as major products. We focused on the use of recyclable and green temporary protecting groups (in a one‐pot reaction) and on the modulation of the intramolecular hydrogen‐bonding network using selected arylboronic acids. A complete scalable procedure leading to a single regioisomer from unprotected methyl α‐ d ‐glucopyranoside is presented.