Categories: Synthesis of N-Heterocycles > Synthesis of cyclic amines >
Synthesis of azetidines
Recent Literature
A straightforward synthesis of various 1,3-disubstituted azetidines has been
accomplished via the alkylation of primary amines with in situ generated
bis-triflates of 2-substituted-1,3-propanediols.
M. C. Hillier, C.-Y. Chen, J. Org. Chem., 2006, 71, 7885-7887.
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.
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.
N-Tosyl-3-halo-3-butenylamines underwent efficient Ullmann-type
coupling to afford 2-alkylideneazetidines, which could be readily converted to
the corresponding β-lactams by oxidation with O3.
H. Lu, C. Li, Org. Lett., 2006, 8, 5365-5367.
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.
tert-Butyl hypoiodite is a mild and powerful reagent for the
cyclization of N-alkenylamides leading to various N-heterocycles.
N-alkenylsulfonamides gave three- to six-membered saturated N-heterocycles
in good yields, whereas alkenylbenzamide derivatives afforded
N-, O- or N-, S-heterocycles.
S. Minakata, Y. Morino, Y. Oderaotoshi, M. Komatsu, Org. Lett.,
2006, 8, 3335-3337.
Thermal and silver-catalyzed [2+2] cycloadditions of imines to
methylenecyclopropane derivatives gave 2-alkoxyazetidines, which are versatile
building blocks for the synthesis of various other compounds such as α-cyclopropanated
β-amino acids.
T. Nishimura, Y. Yasuhara, T. Hayashi, Angew. Chem. Int. Ed., 2006, 45, 5164-5166.
Functionalized 2-(sulfonylimino)-4-(alkylimino)azetidine derivatives were
prepared in good to excellent yields via a copper-catalyzed multicomponent
reaction of readily available terminal alkynes, sulfonyl azides, and
carbodiimides without the assistance of a base under very mild conditions.
X. Xu, D. Cheng, J. Li, H. Guo, J. Yan, Org. Lett., 2007,
9, 1585-1587.
