Categories: C-O Bond Formation >
Synthesis of carbonates and related compounds
Related: |
|
Recent Literature
Mg(ClO4)2 is a stable and specific activator of
1,3-dicarbonyl compounds, that allows a smooth, direct synthesis of aryl and
alkyl ethyl carbonates.
G. Bartoli, M. Bosco, A. Carlone, M. Locatelli, E. Marcantoni, P. Melchiorre,
P. Palazzi, L. Sambri, Eur. J. Org. Chem., 2006,
4429-4434.
Treatment of 4,5-dichloro-6-oxopyridazin-1(6H)-carboxylates with
aliphatic or aromatic alcohols in the presence of potassium tert-butoxide
in toluene at room temperature provides carbonates in good yields. Alkyl and
aryl 4,5-dichloro-6-oxopyridazin-1(6H)-carboxylates are therefore
efficient, stable, and ecofriendly alternatives to chloroformates.
H. K. Moon, G. H. Sung, Y.-J. Yoon, H. J. Yoon,
Synlett, 2016, 27, 1577-1581.
A very efficient Zinc acetate-catalyzed protection of alcohols as Boc
derivatives can be applied to primary, secondary and aromatic alcohols,
providing the first example of a generally applicable method.
G. Bartoli, M. Bosco, A. Carlone, R. Dalpozzo, M. Locatelli, P. Melchiorre, P.
Palazzi, L. Sambri, Synlett, 2006,
2104-2108.
A photo-on-demand in situ synthesis of chloroformates of primary alkyl
alcohols in the presence of CHCl3 and oxygen followed by addition of
alcohols or amines enables a one-pot synthesis of carbonates and carbamates,
respectively.
F. Liang, M. Yanai, Y. Suzuki, A. Tsuda,
Org. Lett., 2020, 22, 3566-3569.
Carbon tetrabromide catalyzes O-tert-butoxycarbonylation of
functionalized phenols without any side reactions (bromination, addition of CBr3
to a double bond, and formation of symmetrical diaryl carbonates, cyclic
carbonates, or carbonic-carbonic anhydrides). The parent phenols are regenerated
from the O-t-Boc derivatives by the catalyst system CBr4-PPh3
without affecting other functional groups.
S. V. Chankeshwara, R. Chebolu, A. K. Chakraborti, J. Org. Chem., 2008,
73, 8615-8618.
Triphenylphosphine is a suitable organocatalyst for the chemoselective O-tert-butoxycarbonylation
of phenols under neutral and neat conditions.
R. Chebolu, S. V. Chankeshwara, A. K. Chakraborti, Synthesis, 2008,
1448-1454.
The reaction of Grignard reagents with alkyl imidazolecarboxylates, which
were prepared from alcohols with carbonyl diimidazole, gave the
corresponding esters in good to excellent yields.
T. Werner, A. G. M. Barrett, J. Org. Chem., 2006,
71, 4302-4304.
An efficient method to activate hydroxyl groups of amino alcohols has been
developed, which avoids the use of toxic reagents and tolerates various
functional groups. This strategy has been applied to the synthesis of
functionalized p-methoxyphenyl-protected azetidines, pyrrolidines, and
piperidines.
R. M. de Figueiredo, R. Fröhlich, M. Christmann, J. Org. Chem., 2006,
71, 4147-4154.
A bimetallic titanium complex [(salen)TiO]2 catalyzes the asymmetric addition of ethyl cyanoformate to aldehydes leading to
cyanohydrin carbonates with high enantiomeric excesses.
Y. N. Belokon, A. J. Blacker, L. A. Clutterbuck, M. North, Org. Lett.,
2003, 5, 4505-4507.