Categories: Synthesis of N-Heterocycles > Synthesis of cyclic amines >
Synthesis of pyrrolidines
Recent Literature
A new efficient method for the N-heterocyclization of primary amines
with diols catalyzed by a Cp*Ir complex was developed. A variety of five-,
six-, and seven-membered cyclic amines were synthesized in good to excellent
yields.
K.-I. Fujita, T. Fujii, R. Yamaguchi, Org. Lett., 2004, 6,
3525-3528.
A one-pot synthesis of nitrogen-containing heterocycles from alkyl dihalides
and primary amines and hydrazines occurs under microwave irradiation via a
simple and efficient cyclocondensation in an alkaline aqueous medium.
Y. Ju, R. S. Varma, J. Org. Chem., 2006, 71, 135-141.
Optically pure C2-symmetrical cyclic amines were
efficiently synthesized from the corresponding diols obtained from an
enantioselective borohydride reduction of diketones in the presence of a chiral
β-ketoiminato cobalt(II) catalyst.
M. Sato, Y. Gunji, T. Ikeno, T. Yamada, Synthesis, 2004,
1434-1438.
A mild, effective gold(I)-catalyzed hydroamination of unactivated olefins to
form protected nitrogen heterocycles has been developed. The substrate scope
is broader than in reactions realized with late-transition-metal catalyst
systems.
X. Han, R. A. Widenhoefer, Angew. Chem. Int. Ed., 2006, 45, 1747-1749.
Treatment of an N-4-pentenyl or N-5-hexenyl urea with a
catalytic 1:1 mixture of a gold(I) N,N-diaryl imidazol-2-ylidine complex and
AgOTf gave the corresponding nitrogen heterocycle in excellent yield via an
intramolecular exo-hydroamination.
C. F. Bender, R. A. Widenhoefer, Org. Lett., 2006, 8, 5303-5305.
An asymmetric intramolecular hydroamination of allenes catalyzed by
phosphinegold(I)-bis-p-nitrobenzoate complexes is applicable to the
enantioselective formation of vinyl pyrrolidines and piperidines in high ee.
R. L. LaLonde, B. D. Sherry, E. J. Kang, F. D. Toste, J. Am. Chem. Soc., 2007,
129, 2452-2453.
The stereoselective synthesis of N-acyl- and N-Boc-protected
pyrrolidines via Pd-catalyzed reactions of γ-(N-acylamino) alkenes and
γ-(N-Boc-amino) alkenes with aryl bromides proceeds with generally high
levels of diastereoselectivity by formation of two bonds in a single operation.
M. B. Bertrand, J. P. Wolfe, Tetrahedron, 2005,
61, 6447-6459.
A mild and facile Pd-catalyzed intramolecular hydroamination of unactivated
alkenes takes place at room temperature and tolerates acid-sensitive functional
groups. The tridentate ligand on Pd effectively inhibits β-hydride elimination, thus
the formation of hydroamination products is preferred over oxidative amination
products.
F. E. Michael, B. M. Cochran, J. Am. Chem. Soc.,
2006, 128, 4246-4247.
The gold(I)-catalyzed reaction of methylenecyclopropanes with sulfonamides
produces the corresponding pyrrolidine derivatives in moderate to good
yields via a domino ring-opening ring-closing hydroamination process.
M. Shi, L.-P. Liu, J. Tang, Org. Lett.,
2006, 8, 4043-4046.
A simple iron-catalyzed intramolecular hydroamination of unactivated olefins
proceeds under mild conditions and tolerates aminoolefins containing halide
moieties.
K. Komeyama, T. Morimoto, K. Takaki, Angew. Chem. Int. Ed., 2006, 45, 2938-2941.
Hoveyda-Grubbs catalyst in combination with BF3·OEt2 efficiently promotes
tandem cross metathesis intramolecular aza-Michael reaction between enones and
unsaturated carbamates resulting in the creation of β-amino carbonyl units. The
use of microwave irradiation dramatically accelerates the process, but also inverts the
stereoselectivity in the addition process.
S. Fustero, D. Jiménez, M. Sánchez-Roselló, C. del Pozo, J. Am. Chem. Soc., 2007,
129, 6700-6701.
1,3-Dipolar cycloaddition of in situ generated azomethine ylides to electron
deficient olefins catalyzed by tris(pentafluorophenyl)borane is described.
P. Srihari, S. R. Yaragorla, D. Basu, S. Chandrasekhar, Synthesis, 2006, 2646-2648.
The Au(I)-catalyzed intramolecular hydroamination of N-allenyl
carbamates was effective for the formation of various cyclic amines. γ-Hydroxy
and δ-hydroxy allenes underwent Au-catalyzed intramolecular
hydroalkoxylation to form the corresponding
oxygen heterocycles in good yield. 2-Allenyl indoles
underwent Au-catalyzed intramolecular hydroarylation to form 4-vinyl tetrahydrocarbazoles in good yield.
Z. Zhang, C. Liu, R. E. Kinder, X. Han, H. Qian, R. A. Widenhoefer, J. Am. Chem. Soc.,
2006, 128, 9066-9073.
Under selected conditions, the Zr-catalyzed reaction of EtMgCl with imines
produces C,N-dimagnesiated compounds, which can be further trapped with
electrophiles. The overall transformation provides a new route to
bifunctional or cyclic nitrogen-containing compounds such as
1-azaspirocyclic γ-lactams, pyrrolidines and azetidines.
V. Gandon, P. Bertus, J. Szymoniak, Synthesis, 2002, 1115-1120.
Ph3PAuOTf catalyzes efficient intra- and intermolecular
hydroamination of unactivated olefins with sulfonamides.
J. Zhang, C.-G. Yang, C. He, J. Am. Chem. Soc.,
2006, 128, 1798-1799.
Iodocyclization of unsaturated tosylamides promoted by Oxone oxidation of KI
afforded, in good yields, N-tosyl iodopyrrolidines and piperidines. A
new, simple method for the conversion of alcohols to tosylamides is
presented.
M. C. Marcotullio, V. Campagna, S. Sternativo, F. Costantino, M. Curini, Synthesis, 2006, 2760-2766.
The aza-Payne rearrangement of 2,3-aziridin-1-ols under basic conditions gives
epoxy amines. Subsequent nucleophilic attack of the epoxide by
dimethylsulfoxonium methylide yields a bis-anion, which upon a 5-exo-tet
ring-closure yields the desired pyrrolidine. This process takes place with
complete transfer of stereochemical fidelity and can be applied to sterically
hindered aziridinols.
J. M. Schomaker, S. Bhattacharjee, J. Yan, B. Borhan, J. Am. Chem. Soc., 2007,
129, 1996-2003.
J. M. Schomaker, S. Bhattacharjee, J. Yan, B. Borhan, J. Am. Chem. Soc., 2007,
129, 1996-2003.
An intramolecular iodo-aldol cyclization of prochiral α-substituted enoate
aldehydes and ketones produces hetero- and carbocycles containing quaternary centers adjacent
to secondary or tertiary centers. The reactions occur in good yields and are
highly trans-selective with hydroxyl and iodomethyl
groups on opposite faces of the ring system.
F. Douelle, A. S. Capes, M. F. Greaney, Org. Lett., 2007,
9, 1931-1934.
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 successful stereochemical reversal in AgOAc catalyzed [3+2] cycloaddition is
based on the formation of hydrogen bonding between ligand and reactant. Simple
ligand design provides an efficient and convenient route to prepare both
enantiomers of a chiral compound.
W. Zeng, G.-Y. Chen, Y.-G. Zhou, Y.-X. Li, J. Am. Chem. Soc., 2007,
129, 750-751.
Chiral complexes of calcium promote asymmetric 1,4-addition reactions and [3+2]
cycloaddition reactions of α-amino acid derivatives with α,β-unsaturated
carbonyl compounds. The reactions proceeded smoothly in the presence of 5-10 mol
% of the chiral calcium catalyst to afford the desired adducts in high yields
with high diastereo- and enantioselectivities.
S. Saito, T. Tsubogo, S. Kobayashi, J. Am. Chem. Soc., 2007,
129, 5364-5365.
A [3 + 2]-annulation of N-Ts-α-amino aldehydes and
1,3-bis(silyl)propenes allows an efficient, stereoselective synthesis of
densely functionalized pyrrolidines.
P. Restorp, A. Fischer, P. Somfai, J. Am. Chem. Soc., 2006, 128, 12646-12647.
Catalytic hydrogenation of acetylenic aldehydes using a chirally modified
cationic rhodium catalysts enables highly enantioselective reductive
cyclization to afford cyclic allylic alcohols. Using an achiral
hydrogenation catalyst, some chiral racemic acetylenic aldehydes engage in
highly syn-diastereoselective reductive cyclizations.
J. U. Rhee, M. J. Krische, J. Am. Chem. Soc., 2006, 128, 10674-10675.
The reaction of 1,1-cyclopropandiesters with aldimines, generated in situ
by the condensation of primary amines or anilines with aldehydes, in the
presence of Yb(OTf)3 as catalyst leads to pyrrolidines in good
yields.
C. A. Carson, M. A. Kerr, J. Org. Chem., 2005, 70, 8242-8244.
A tandem ring-opening-cyclization reaction of cyclopropanes with imines in
the presence of 5 mol% of scandium triflate was developed for the highly
diastereoselective synthesis of multisubstituted pyrrolidines.
Y.-B. Kang, Y. Tang, X.-L. Sun, Org. Biomol. Chem., 2006, 4, 299-301.
Palladium-catalyzed inter- and intramolecular enyne coupling
reactions were developed. The
reaction involves the acetoxypalladation of the alkyne, followed by the
insertion of the alkene and the protonolysis of the carbon-palladium bond. The coupling
allows the construction of synthetically important carbo- and
heterocycles.
L. Zhao, X. Lu, W. Xu, J. Org. Chem., 2005, 70, 4059-4063.
Indium hydride generated from readily available Et3SiH and InCl3
offers mild conditions and low toxicity, and is therefore a promising
alternative to Bu3SnH.
N. Hayashi, I. Shibata, A. Baba, Org. Lett., 2004, 6,
4981-4983.
A
new methodology for the cycloisomerization of dienes using a Grubbs carbene
complex and trimethylsilyl vinyl ether has been established.
Y. Terada, M.
Arisawa, A. Nishida, Angew. Chem., 2004, 116,
4155-4159.
A novel alkenylative cyclization of enyne was developed using Cp*RuCl(cod)
under ethylene gas at room temperature.
M. Mori, N. Saito, D. Tanaka, M. Takimoto, Y. Sato, J. Am. Chem. Soc., 2003, 125, 5606-5607.
A convenient two-step preparation of alkylidenepyrrolidines is reported.
M. C. Elliot, S. V. Wordingham, Synthesis, 2006, 1162-1170.
Reductive
radical cyclization of N-allyl-N-dimethylphosphinoyl-2-aminopropyl
phenyl selenide using tris(trimethylsilyl)silane (TTMSS) / AIBN under UV
irradiation gave the corresponding pyrrolidine in 74% yield and a cis/trans ratio of 10/1
which was superior to thermal cyclization
D. Shanks, S. Berlin, M. Besev,
H. Ottosson, L. Engman, J. Org. Chem., 2004, 69,
1487-1491.
A chiral iridium diphosphine complex catalyzes an enantioselective
intramolecular Pauson-Khand-type reaction to give various chiral bicyclic
cyclopentenones. A low partial pressure of carbon monoxide is important to
achieve excellent enantioselectivity.
T. Shibata, N. Toshida, M. Yamasaki, S. Maekawa, K. Takagi, Tetrahedron, 2005,
61, 9974-9979.
The reaction of various 1,6-enynes with N2CHSiMe3 in the
presence of RuCl(COD)Cp* as catalyst precursor leads to the general formation of
alkenylbicyclo[3.1.0]hexanes at room temperature in good yield with high
stereoselectivity. The catalytic formation of alkenylbicyclo[3.1.0]hexanes also
takes place in the presence of N2CHCO2Et or N2CHPh.
F. Monnier, C. Vovard-Le Bray, D. Castillo, V. Aubert, S. Dérien, P. H.
Dixneuf, L. Toupet, A. Ienco, C. Mealli, J. Am. Chem. Soc., 2007,
129, 6037-6049.
F. Monnier, C. Vovard-Le Bray, D. Castillo, V. Aubert, S. Dérien, P. H.
Dixneuf, L. Toupet, A. Ienco, C. Mealli, J. Am. Chem. Soc., 2007,
129, 6037-6049.
A new Pd-catalyzed oxidation reaction for the stereospecific conversion of
enynes into cyclopropyl ketones proceeds with net inversion of geometry with
respect to the starting olefin. This result is consistent with a mechanism in
which the key cyclopropane-forming step involves nucleophilic attack of a
tethered olefin onto the PdIV-C bond.
L. L. Welbes, T. W. Lyons, K. A. Cychosz, M. S. Sanford, J. Am. Chem. Soc., 2007,
129, 5836-5837.
| Related:
|
