Categories: Synthesis of O-Heterocycles, C-O Bond Formation, Synthesis of cyclic ethers >
Synthesis of tetrahydropyrans
Recent Literature
The platinum-catalyzed hydroalkoxylation of γ- and δ-hydroxy olefins
tolerated various substitution patterns and a number of functional groups
including pivaloate and acetate esters, amides, silyl and benzyl ethers, and
pendant hydroxyl and olefinic groups.
H. Qian, X. Han, R. A. Widenhoefer, J. Am. Chem. Soc.,
2004, 126, 9536-9537.
H. Qian, X. Han, R. A. Widenhoefer, J. Am. Chem. Soc.,
2004, 126, 9536-9537.
The reaction of tertiary 1,4- and 1,5-diols with cerium ammonium nitrate at room
temperature gives tetrahydrofuran and tetrahydropyran derivatives in high yield
and stereoselectivity. Various fragrant compounds have been synthesized using
this method.
E. J. Alvarez-Manzaneda, R. Chabouna, E. Alvarez, E. Cabrera, R.
Alvarez-Manzaneda, A. Haidour, J. M. Ramos, Synlett, 2006,
1756-1758.
Lanthanide triflates are efficient catalysts for the intramolecular
Markovnikov-type hydroalkoxylation/cyclization of primary/secondary and
aliphatic/aromatic hydroxyalkenes in room temperature ionic liquids (RTILs) to
give five- and six-membered oxygen heterocycles in very good yields.
A. Dzudza, T. J. Marks, Org. Lett., 2009,
11, 1523-1526.
A mild, general, and functional group tolerant intramolecular
hydroalkoxylation and hydroacyloxylation of unactivated olefins using a Co(salen)
complex, an N-fluoropyridinium salt, and a disiloxane reagent at room temperature
provides five- and six-membered cyclic ethers and lactones. The powerful Co catalyst system
also enables the deprotective hydroalkoxylation of O-protected alkenyl alcohol
and hydroacyloxylation of alkenyl esters.
H. Shigehisa, M. Hayashi, H. Ohkawa, T. Suzuki, H. Okayasu, M. Mukai, A.
Yamazaki, R. Kawai, H. Kikuchi, Y. Satoh, A. Fukuyama, K. Hiroya, J. Am. Chem. Soc., 2016,
138, 10084-10087.
Silver(I) triflate catalyzes intramolecular additions of hydroxyl or carboxyl groups to olefins
in good to excellent yields for a range of substrates under relatively mild conditions. This
reaction is one of the simplest methods to construct cyclic ethers or
lactones.
C.-G. Yang, N. W. Reich, Z. Shi, C. He, Org. Lett.,
2005, 7, 4553-4556.
A Cu(I)-Xantphos system catalyzed the intramolecular hydroalkoxylation of
unactivated terminal alkenes, providing five- and six-membered cyclic ethers. A
possible reaction pathway involves an addition of a Cu-O bond across the C-C
double bond. The use of (R)-DTBM-SEGPHOS as ligand enabled an
enantioselective reaction with moderate enantioselectivity.
H. Murayama, K. Nagao, H. Ohmiya, M. Sawamura, Org. Lett.,
2015,
17, 2039-2041.
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.
A combination of Pd(II)/bis-sulfoxide C-H activation and Lewis acid co-catalysis
enables the synthesis of chroman, isochroman, and pyran motifs from a wide range
of alcohols. Mechanistic studies suggest that the reaction proceeds via initial
C-H activation followed by a novel inner-sphere functionalization pathway.
S. E. Ammann, G. T. Rice, M. C. White, J. Am. Chem. Soc., 2014,
136, 10834-10837.
An In(OTf)3-catalyzed (3,5) oxonium-ene type cyclization enables
the facile construction of various multisubstituted tetrahydrofurans and
tetrahydropyrans. Mechanistic investigations unveiled an In(OTf)3-catalyzed
skeletal reorganization of the tetrahydrofuran to its thermodynamic isomer under
thermal conditions.
T.-P. Loh, Q.-Y. Hu, K.-T. Tan, H.-S. Cheng,
Org. Lett., 2001, 3, 2669-2672.
A mild and convenient free-radical cyclization of organohalides in the presence
of a NiCl2 • DME/Pybox complex as the catalyst and zinc powder in
methanol efficiently gives carbo-, oxa-, and azacycles as products in high
yields from unsaturated alkyl halides.
H. Kim, C. Lee, Org. Lett., 2011,
13, 2050-2053.
Key step of an eco-friendly and highly diastereoselective synthesis of
substituted cis-2,6-piperidines and cis-2,6-tetrahydropyrans is an
iron-catalyzed thermodynamic equilibration of 2-alkenyl 6-substituted
piperidines and 2-alkenyl 6-substituted tetrahydropyrans allowing the isolation
of enriched mixtures of the most stable cis-isomers.
A. Guérinot, A. Serra-Muns, C. Gnamm, C. Bensoussan, S. Reymond, J. Cossy, Org. Lett., 2010,
12, 1808-1811.
The gold(I)-catalyzed cyclization of chiral monoallylic diols to form
tetrahydropyrans is highly stereoselective. Substrates that differ only in
olefin geometry provide enantiomeric products from formal SN2′
reactions in high yields with excellent chirality transfer. The allylic alcohol
stereochemistry also efficiently controls the facial selectivity when the
substrates include additional stereocenters.
A. Aponick, B. Biannic, Org. Lett., 2011,
13, 1330-1333.
The use of a cation-binding oligoEG catalyst and KF as the base enables a highly
enantioselective cycloetherification for the straightforward synthesis of
enantioenriched tetrahydrofurans, tetrahydropyrans, and oxepanes from ε-, ζ-,
and η-hydroxy-α,β-unsaturated ketones.
A. P. Jadhav, J.-A Oh, I.-S. Hwang, H. Yan, C. E. Song, Org. Lett.,
2018, 20, 5319-5322.
Highly acidic confined imino-imidodiphosphate (iIDP) Brønsted acids catalyze the
asymmetric Prins cyclization of both aliphatic and aromatic aldehydes. Diverse
functionalized 4-methylenetetrahydropyrans are obtained in very good yields and
with high regio- and enantioselectivities.
L. Liu, P. S. J. Kaib, A. Tap, B. List, J. Am. Chem. Soc., 2016,
138, 10822-10825.
2-(Arylmethylene)cyclopropylcarbinols could be converted to the corresponding
tetrahydropyrans stereoselectively in the presence of Brønsted acids under mild
conditions. A plausible Prins-type reaction mechanism has been proposed.
G.-Q. Tian, M. Shi, Org. Lett., 2007,
9, 2405-2408.
Exo-3-furanylidenes and 3-pyranylidenes products having cis-2,5
and cis-2,6 substitution were synthesized from terminally substituted
alkynyl alcohols with various aldehydes via Prins-type cyclization and trapping
of the resulting vinyl cations as vinyl triflates in good yields. Vinyl
triflates underwent a subsequent stereoselective hydrolysis to give the
corresponding 3-acyl-substituted products.
S. N. Chavre, H. Choo, J. K. Lee, A. N. Pae, Y. Kim, Y. S. Cho, J. Org. Chem., 2008,
73, 7467-7471.
Cyclization of δ-halocarbanions to cyclobutanes is a relatively slow process,
thus formation of tetrahydropyran derivatives via addition to aldehydes and
subsequent cyclization is possible in high yield. A simple mechanistic
discussion, optimization of the reaction conditions, and the scope of the
reaction are discussed.
M. Barbasiewicz, A. Brud, M. Mąkosza, Synthesis, 2007,
1209-1213.
Phosphomolybdic acid catalyzes efficiently the Prins cyclization of homoallylic
alcohols with aldehydes in water at room temperature to provide
tetrahydropyran-4-ol derivatives in high yields with all cis-selectivity.
The use of phosphomolybdic acid in water makes this procedure simple, convenient,
cost-effective, and environmentally friendly.
J. S. Yadav, B. V. S. Reddy, G. G. K. S. N. Kumar, S. Aravind, Synthesis, 2008,
395-400.
The rhenium(VII) complex O3ReOSiPh3 is a particularly
effective catalyst for Prins cyclizations using aromatic and α,β-unsaturated
aldehydes. The reaction conditions are mild, and the highly substituted
4-hydroxytetrahydropyran products are formed stereoselectively.
K. Tadpetch, S. D. Rychnovsky, Org. Lett.,
2008,
10, 4839-4842.
InCl3 mediates cyclizations between homoallyl (thio)alcohols with aldehydes to provide polysubstituted tetrahydropyrans and
thiacyclohexanes in high yields with excellent diastereoselectivities. The
configuration of the tetrahydropyrans depends on the geometry
of the homoallyl alcohols; whereas both cis- and trans-homoallyl mercaptans provide the same major diastereomers.
X.-F. Yang, J. T. Mague, C.-J. Li, J. Org. Chem., 2001,
66, 739-747.
1-n-Butyl-3-methylimidazolium chloroaluminate [bmin]Cl .
AlCl3
was successfully employed as a reaction medium for Prins cyclizations, to
produce 4-chlorotetrahydropyran derivatives in short reaction times.
J. S. Yadav, B. V. S. Reddy, M. S. Reddy, N.
Niranjan, A. R. Prasad, Eur. J. Org. Chem., 2003, 1779-1783.
Aldehydes undergo rapid and selective coupling with 3-buten-1-ol in the
presence of 20 mol% of niobium(V) chloride to afford 4-chlorotetrahydropyran
derivatives under extremely mild conditions in excellent yields. Similar
halogenated tetrahydropyrans are also obtained using gallium(III) halides.
J. S. Yadav, B. V. Subba Reddy, M. K. Gupta, S. K. Biswas, Synthesis,
2004, 2711-2715.
An efficient method allows the construction of 2,6-cis-4,5-dibromo-tetrasubstituted
tetrahydropyran rings with well-controlled stereochemistry in good yields.
F. Liu, T.-P. Loh, Org. Lett., 2007,
9, 2063-2066.
F. Liu, T.-P. Loh, Org. Lett., 2007,
9, 2063-2066.
A highly stereoselective route to 2,4,5-trisubstituted tetrahydropyrans
employs an intramolecular allylation of a (Z)-allylsilane onto an
aldehyde under Brønsted acid activation.
P. J. Jervis, B. M. Kariuki, L. R. Cox, Org. Lett.,
2006, 8, 4637-4640.
A new convergent synthetic approach to the 2-hydroxypyran motif common to many
naturally occurring structures includes the esterification of two fragments and
a subsequent intramolecular reductive cyclization.
L. V. Heumann, G. E. Keck, Org. Lett., 2007,
9, 1951-1954.
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.
A comparative study of chiral Mo- and Ru-based catalysts to promote
enantioselective synthesis of 2,6-disubstituted pyrans and piperidines through
asymmetric ring-opening/cross-metathesis reactions demonstrated the critical
complementarity that exists between the two classes of chiral catalysts.
G. A. Cortez, C. A. Baxter, R. R. Schrock, A. H. Hoveyda, Org. Lett., 2007,
9, 2871-2874.
Treatment of 3-[(alkoxycarbonyl)alkyl]-substituted conjugated cycloalkenones
with diisobutylaluminum hydride at -78 °C followed by acid quenching
furnishes spiro ethers, whereas the corresponding 3-(carboxyalkyl)-substituted
cycloalkenones generate spiro lactones upon reaction with sodium borohydride
at 30 °C followed by acid quenching.
M.-C. P. Yeh, Y.-C. Lee, T.-C. Young, Synthesis, 2006, 3621-3624.
An efficient and regioselective Yb(OTf)3-promoted
palladium-catalyzed oxidative cyclization of γ-heteroalkenyl β-keto amides
has been developed. Under simple aerobic condition, various six-, seven-,
and eight-membered-ring N- and O-heterocycles were obtained in excellent yield.
K.-T. Yip, J.-H. Li, O.-Y. Lee, D. Yang, Org. Lett.,
2005, 7, 5717-5719.
Diastereoselective and Enantioselective Construction of Cyclic Ethers Stereocontrolled Construction of Cyclic Ethers Enantioselective Construction of Naturally-Occurring Cyclic Ethers |