Russian Journal of Organic Chemistry, Vol. 41, No. 4, 2005, pp. 625–626. From Zhurnal Organicheskoi Khimii, Vol. 41, No. 4, 2005, pp. 634–635.
Original English Text Copyright © 2005 by Shirini, Zolfigol, Mallakpour.
SHORT
COMMUNICATIONS
Mild and Efficient Procedure for Acetylation and Formylation
of Alcohols in the Presence of Mg(HSO4)2*
F. Shirini1, M. A. Zolfigol2, and B. Mallakpour1
1 Department of Chemistry, College of Science, Guilan University, Rasht, I. R. Iran
fax: +981313220066; e-mail: shirini@guilan.ac.ir
2 Departament of Chemistry, College of Science, Bu-Ali Sina University, Hamadan, Iran
e-mail: zolfi@sadaf.basu.ac.ir
Received April 20, 2003
Acetylation and formylation of hydroxy groups are
among the most widely used transformations in or-
ganic synthesis [1, 2]. Direct esterification of alcohols
with carboxylic acids is generally avoided since the
equilibrium established between the reactants and the
products requires the use of excess initial compounds
or removal of water from the reaction mixture to drive
the process to completion. Many useful methods for
esterification have been reported [3, 4]. Some recently
developed procedures utilize organic, inorganic, and
organometallic reagents. However, most of these
methods are not free from one or more of the following
disadvantages: long reaction time, severe conditions,
occurrence of side processes, inaccessibility of re-
quired reagents, and poor yields of the target products.
of formylating agents, and thermal instability of the
reagents.
In continuation of our studies on the use of
magnesium hydrogen sulfate Mg(HSO4)2 in organic
chemistry [11, 12], in the present communication we
describe its application as efficient catalyst for acetyla-
tion and formylation of alcohols. All reactions were
performed under mild heterogeneous conditions (see
table). However, the developed procedure was inef-
ficient in the acetylation and formylation of allyl
alcohols (see table, run nos. 6, 15). The reactions are
clean, the product yields reach 90%, and the procedure
is simple. Further studies on new applications of
Mg(HSO4)2 are now in progress in our laboratories.
Mg(HSO4)2, CH2Cl2
reflux
Acetylation of alcohols is usually performed with
the use of acetic anhydride or acetyl chloride in the
presence of a base such as triethylamine or pyridine.
The rate of acetylation is known to considerably
increase when 4-dimethylaminopyridine is used as co-
catalyst [2]. p-Toluenesulfonic acid (protic acid) [5]
and Lewis acids, e.g., Cu(OTf)2 [6], as well as tri-
methylsilyl trifluoromethanesulfonate [7] and chloro-
trimethylsilane [8], were also efficient as catalysts in
acetylation of alcohols.
R'COOH
+
ROH
R'COOR
For R, see table; R' = H, Me.
General procedure for acetylation and formyla-
tion of alcohols in the presence of Mg(HSO4)2.
A mixture of 1 mmol of alcohol, 1 mmol of acetic or
ormic acid, and 0.75 mmol of Mg(HSO4)2 in 5 ml of
dry methylene chloride was heated under reflux over
a period indicated in table. The progress of reactions
was monitored by TLC. When the reaction was com-
plete, the mixture was filtered, and the solid precipitate
was washed with 10 ml of methylene chloride. The
filtrate was combined with the washings, the solvent
was removed, and the residue was purified by column
chromatography on silica gel.
Formylation is also a very important process in or-
ganic chemistry. Although various formylating agents
have been reported previously [9, 10], there are still
serious limitations to the preparation of formates
because of drastic conditions, use of uncommon re-
agents, formation of undesirable or toxic by-products,
application of expensive catalysts for the preparation
The authors are thankful to the Guilan University
Council for partial support of this work.
* The original article was submitted in English.
1070-4280/05/4104-0625 © 2005 Pleiades Publishing, Inc.
Shirini
