Categories: C-C Bond Formation > Cyclic compounds > Cycloalkanes
Synthesis of cyclopropanes
| Related: |
 |
 |
Name Reactions
Wurtz Reaction (intramolecular modification)
Recent Literature
A new class of zinc reagents (RXZnCH2Y) derived from an appropriate
organozinc was proved to be very effective for the cyclopropanation of olefins.
The reactivity can be regulated by the electronic and steric nature of the RX
group. Chiral (iodomethyl)zinc species were tested for asymmetric
cyclopropanation (see article).
J. C. Lorenz, J. Long, Z. Yang, S. Xue, X. Xie, Y. Shi, J. Org. Chem.,
2004, 69, 209-212.
A new class of anionic, boron-bridged analogues of the box ligands was developed.
These borabox ligands showed a considerable potential for asymmetric
cyclopropanation and desymmetrizations of meso diols.
C. Mazet, V. Koehler, A. Pfaltz, Angew. Chem., 2005, 117,
4966-4969.
A samarium-promoted cyclopropanation can be carried out on unmasked (E)-
or (Z)-α,β-unsaturated carboxylic acids. In all cases the process is
completely stereospecific and stereoselective. A mechanism has been proposed.
J. M. Concellón, H. Rodríguez-Solla, C. Simal, Org. Lett., 2007,
9, 2685-2688.
Efficient, simple, cheap, and environmentally benign preparations of
cyclopropanes were achieved. One method is based on a 3-exo-trig cyclisation of
various electron-deficient 2-iodoethyl-substituted olefins with zinc powder in a
mixture of t-butyl alcohol and water, and the other on a 3-exo-tet
cyclisation of various 1,3-dihalopropanes with zinc powder in ethanol.
D. Sakuma, H. Togo, Tetrahedron, 2005, 61, 10138-10145.
D. Sakuma, H. Togo, Tetrahedron, 2005, 61, 10138-10145.
The first Corey-Chaykovsky epoxidation and cyclopropanation using trimethyl
sulfonium iodide/trimethyl sulfoxonium iodide and KOH as base in the recyclable
ionic liquid, (bmim)PF6 are described.
S. Chandrasekhar, Ch. Narasihmulu, V. Jagadeshwar, K. Venkatram Reddy,
Tetrahedron Lett., 2003, 44, 3629-3630.
Three highly enantio- and diastereoselective one-pot procedures for the
synthesis of cyclopropyl and iodocyclopropyl alcohols with up to four contiguous
stereocenters are reported. Route 1 and 2 involve asymmetric addition of an
alkylzinc reagent to an enal followed by diastereoselective cyclopropanation
using either diiodomethane or iodoform to generate the zinc carbenoid, leading
to cyclopropyl or iodocyclopropyl alcohols, respectively. Route 3 entails
asymmetric vinylation of an aldehyde with divinylzinc reagents and subsequent
diastereoselective cyclopropanation.
H. Y. Kim, A. E. Lurain, P. Garcia-Carcia, P. J. Carroll, P. J. Walsh, J. Am.
Chem. Soc., 2005, 127, 13138-13139.
H. Y. Kim, A. E. Lurain, P. Garcia-Carcia, P. J. Carroll, P. J. Walsh, J. Am.
Chem. Soc., 2005, 127, 13138-13139.
H. Y. Kim, A. E. Lurain, P. Garcia-Carcia, P. J. Carroll, P. J. Walsh, J. Am.
Chem. Soc., 2005, 127, 13138-13139.
The reaction of 1-aryl-2,2,2-trifluorodiazoethanes with alkenes provides
trifluoromethyl-substituted cyclopropanes with high diastereoselectivity and
enantioselectivity in the presence of an adamantylglycine-derived dirhodium
complex Rh2(R-PTAD)4 as catalyst.
J. R. Denton, D. Sukumaran, H. M. L. Davies, Org. Lett., 2007,
9, 2625-2628.
An efficient lithium amide-induced intramolecular cyclopropanation of
bishomoallylic and trishomoallylic epoxides is described. The methodology is
used in an asymmetric synthesis of sabina ketone.
D. M. Hodgson, Y. K. Chung, J.-M. Paris, J. Am. Chem. Soc., 2004,
126, 8654-8655.
Exposure of enynes containing a hydroxyl group at one of the propargylic
positions to catalytic amounts of either PtCl2 or (PPh3)AuCl/AgSbF6
results in a selective rearrangement with formation of bicyclo[3.1.0]hexan-3-one
derivatives. A total synthesis of the terpenes sabinone and sabinol is described.
V. Mamane, T. Gress, H. Krause, A. Fürstner, J. Am. Chem. Soc., 2004,
126, 8654-8655.
V. Mamane, T. Gress, H. Krause, A. Fürstner, J. Am. Chem. Soc., 2004,
126, 8654-8655.
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.
