Manganese Compounds
Name Reactions
Recent Literature
An effective epoxidation of lipophilic alkenes using hydrogen peroxide was
accomplished with a manganese sulfate/bicarbonate catalytic system in an ionic
liquid at room temperature.
K.-H. Tong, K.-Y. Wong, T. H. Chan, Org. Lett., 2003, 5,
3423-3425.
An epoxidation of alkenes using hydrogen peroxide as the terminal
oxidant is promoted by catalytic amounts (1.0-0.1 mol %) of manganese(2+) salts,
and must be performed using at least catalytic amounts of bicarbonate buffer.
Various aryl-substituted, cyclic,
and trialkyl-substituted alkenes were epoxidized under these conditions using 10
equiv of hydrogen peroxide, but monoalkyl-alkenes were not. Additives such as
sodium acetate and salicylic acid enhanced
the rate of the desired epoxidation reaction by 2-3 times. Possible mechanisms for the reaction are discussed.
B. S. Lane, M. Vogt, V. J. DeRosa, K. Burgess, J. Am. Chem. Soc., 2002,
124, 11946-11954.
Readily available Mn(III) complexes catalyze alkene epoxidation by bleach in
good yields. A highly enantioselective epoxidation catalyst was developed
through a logical sequence of ligand modifications.
E. N. Jacobsen, W. Zhang, A. R. Muci, J. R. Ecker, L. Deng, J. Am. Chem.
Soc., 1991,
113, 7063-7064.
The complex [MnII(R,R-mcp)(CF3SO3)2]
is a very efficient and practical catalyst for the epoxidation of a wide
scope of olefins including terminal, tertiary, cis and trans
internal, enones, and methacrylates using peracetic acid as the terminal
oxidant.
A. Murphy, G. Dubois, T. D. P. Stack, J. Am. Chem. Soc., 2003,
125, 5250-5251.
Reactions of vinyl azides with monocyclic cyclopropanols provided pyridines in
the presence of Mn(acac)3, whereas those with bicyclic cyclopropanols
led to the formation of 2-azabicyclo[3.3.1]non-2-en-1-ol derivatives using a
catalytic amount of Mn(acac)3.
Y.-F. Wang, S. Chiba, J. Am. Chem. Soc., 2009,
131, 12570-12572.
Selective addition of radicals to isonitriles enables a general route for the
preparation of N-heteroaromatics. This method utilizes alkenes as
synthetic equivalents of alkynes by coupling homoallylic ring expansion to yield
the formal 6-endo products with aromatization via stereoelectronically
assisted C-C bond scission.
C. J. Evoniuk, G. dos Passos Gomes, M. Ly, F. D. White, I. V. Alabugin, J. Org. Chem.,
2017, 82, 4265-4278.
An efficient rhodium-catalyzed C-H activation and multistep cascade reaction of
benzimidates and alkenes enables the synthesis of diverse difunctionalized
indenones in the presence of Mn(OAc)2. The transformation involves
the cleavage and formation of multiple bonds in one pot under mild reaction
conditions.
N. Lv, Z. Chen, Y. Liu, Z. Liu, Y. Zhang, Org. Lett.,
2017, 19, 2588-2591.
Mn(OAc)3 based regioselective oxidation of various 2-cyclopentenone, 2-cyclohexenone
and aromatic ketone derivatives in benzene afforded the corresponding
tertiary α'-acetoxy oxidation products in good yields.
C. Tanyeli, C. Iyiguen, Tetrahedron,
2003,
59, 7135-7139.
A single electron oxidation of the commercially available CF3SO2Na
(Langlois' reagent) using Mn(OAc)3·2H2O as the oxidant
enables a simple and efficient method for hydrotrifluoromethylation of
unactivated alkenes. The reaction proceeds readily under mild conditions and
tolerates various functional groups.
B. Cui, H. Sun, Y. Xu, L. Li, L. Duan, Y.-M. Li, J. Org. Chem., 2018, 83,
6015-6024.
A Mn(OAc)3-promoted oxidative phosphonylation of N,N-dimethylenaminones
with H-phosphonates provides functionalized β-ketophosphonates in very good
yields under mild reaction conditions. This method offers operational simplicity,
broad substrate scope, and large-scale preparation.
P. Zhou, B. Hu, L. Li, K. Rao, J. Yang, F. Yu, J. Org. Chem.,
2017, 82, 13268-13276.
Mn(OAc)3-mediated phosphinoyl radical addition followed by
CuCN-catalyzed cyanation enables a double-functionalization reaction of alkenes
under mild conditions to afford vicinal cyanophosphinoylation products.
P.-Z. Zhang, L. Zhang, J.-A. Li, A. Shoberu, J.-P. Zou, W. Zhang, Org. Lett.,
2017, 19, 5537-5540.
A Mn(III)-mediated radical cascade cyclization of o-alkenyl aromatic
isocyanides with boronic acids provides N-unprotected
2-aryl-3-cyanoindoles. A possible mechanism involves a sequential intermolecular
radical addition, intramolecular cyclization, and cleavage of a C-C bond under
mild reaction conditions. Either H2O or O2 acts as the
oxygen source for the elimination of benzaldehyde.
L. Liu, L. Li, X. Wang, R. Sun, M.-D. Zhou, H. Wang, Org. Lett., 2021, 23,
5826-5830.
Manganese triacetate mediates an oxidative C-4 arylation of 2-aryl-quinazoline
3-oxides with arylboronic acids to provide 2,4-diarylated quinazoline 3-oxides
in very good yields. The method tolerates various substituents on both aromatic
rings.
R. Samandram , M. Ç. Korukçu, N. Coşkun, Synthesis, 2022, 54,
210-216.