Categories: C-C Bond Formation > Oxygen-containing molecules > Alcohols >
Synthesis of allylic alcohols
| Related: |
 |
 |
Name Reactions
Recent Literature
A highly enantioselective and catalytic vinylation of aldehydes leads to
allylic alcohols that are then transformed to the allylic amines via
Overman's [3,3]-sigmatropic rearrangement of imidates. Oxidative cleavage of
the allylic amines furnishes amino acids in good yields and excellent ee's.
The scope and utility of this method are demonstrated by the synthesis of
challenging allylic amines and their subsequent transformation to valuable
nonproteinogenic amino acids, including both D and L configured
(1-adamantyl)glycine.
Y. K. Chen. A. E. Lurain, P. J. Walsh, J. Am. Chem. Soc., 2002,
124, 12225-12231.
Use of a zirconocene catalyst based on the Brintzinger ligand and catalytic
amounts of methyl aluminoxanes (MAO) effect a >99% regiocontrol of Negishi
carboaluminations of 1-alkynes in toluene.
B. H. Lipshutz, T. Butler, A. Lower, J. Am. Chem. Soc., 2006,
128, 15396-15398.
Hydroboration of a variety of 1-bromo-1-acetylenes with dicyclohexyl borane,
reaction with t-BuLi, and transmetalation to zinc generates a (Z)-disubstituted
vinylzinc reagent. In situ reaction of this reagent with aldehydes generates
(Z)-disubstituted allylic alcohols in high yields.
S.-J. Jeon, E. L. Fischer, P. J. Carroll, P. J. Walsh, J. Am. Chem. Soc.,
2006,
128, 9618-9619.
An easy access to (Z)-trisubstituted allylic alcohols is based on
E to Z isomerization of 1-bromo-1-dialkylvinylboranes upon
reaction with dialkylzinc reagents. Subsequent transmetalation to give (Z)-trisubstituted
vinylzinc species is followed by trapping with aldehydes to furnish a series
of (Z)-trisubstituted allylic alcohols.
Y. K. Chen, P. J. Walsh, J. Am. Chem. Soc.,
2004,
126, 3702-3703.
Various N-acylethylenediamine-based ligands were screened as
catalysts for the asymmetric addition of vinylzinc reagents to aldehydes.
The optimized ligand was found to catalyze the formation of (E)-allylic
alcohols with high enantioselectivities for both aromatic and α-branched
aldehydes, and vinylzinc reagents derived from both bulky and straight chain
terminal alkynes.
C. M. Sprout, M. L. Richmond, C. T. Seto, J. Org. Chem., 2005,
70, 7408-7417.
A highly enantioselective method for catalytic reductive coupling of alkynes
and aldehydes afforded allylic alcohols with complete E/Z
selectivity, generally >95:5 regioselectivity, and in up to 96% ee. In
conjunction with ozonolysis, this process allows the enantioselective
synthesis of α-hydroxy ketones.
K. M. Miller, W.-S. Huang, T. F. Jamison, J. Am. Chem. Soc., 2003,
125, 3442-3443.
A new procedure for catalytic reductive coupling of aldehydes and alkynes
uses Ni(COD)2 with an imidazolium carbene ligand as the catalyst
and triethylsilane as the reducing agent.
G. M. Mahandru, G. Liu, J. Montgomery, J. Am. Chem. Soc.,
2004,
126, 3698-3699.
A bidentate chiral phosphoramide based on a 2,2'-bispyrrolidine skeleton
afforded good yield, efficient turnover, and high enantioselectivity in
allylation reactions of various unsaturated aldehydes with substituted
allylic trichlorosilanes. The reaction of γ-disubstituted allylic
trichlorosilanes allowed the construction of stereogenic, quaternary
centers.
S. E. Denmark, J. Fu, M. J. Lawler, J. Org. Chem.,
2006,
71, 1523-1536.
Highly diastereo- and enantioselective syntheses of 1,5-disubstituted (E)-1,5-anti-pent-2-endiols
and (Z)-1,5-syn-pent-2-endiols have been achieved via the
one-pot coupling of two different aldehydes with bifunctional
γ-boryl-substituted allylborane reagents, which were generated in situ by
the hydroboration of allenes with diisopinocampheylborane. The
stereospecificity is discussed.
E. M. Flamme, W. R. Roush, J. Am. Chem. Soc., 2002,
124, 13644-13645.
On exposure to BuLi, 3-bromo-2-iodocyclopent-2-enol O-TBS ether
undergoes iodine-lithium permutation with complete regioselectivity.
Reaction with different electrophiles affords the corresponding
2-substituted-3-bromocyclopentenol derivatives. Subsequent bromo-lithium
exchange with t-BuLi, followed by reaction with an equal or different
electrophile, affords 2,3-disubstituted cyclopentenols.
M. Luparia, A. Vadalà, G. Zanoni, G. Vidari, Org. Lett.,
2006,
8, 2147-2150.
An iridium-catalyzed, hydrogen-mediated reductive C-C bond formation of
alkynes in the presence of α-ketoesters affords β,γ-unsaturated α-hydroxyesters in
excellent yield, with complete control of olefin geometry and, in most cases,
with excellent regiocontrol.
M.-Y. Ngai, A. Barchuk, M. J. Krische, J. Am. Chem. Soc., 2007,
129, 280-281.
Highly enantioselective direct catalytic reductive couplings of 1,3-enynes
to activated ketones such as ethyl pyruvate have been achieved by using
chirally modified cationic rhodium catalysts in the presence of hydrogen to
afford dienylated α-hydroxy esters with exceptional levels of regio- and
enantiocontrol.
J.-R. Kong, M.-Y. Ngai, M. J. Krische, J. Am. Chem. Soc.,
2006,
128, 718-719.
Slow addition of a terminal alkyne and water to a mixture of an aldehyde,
CrCl2, NiCl2 and a catalytic amount of triphenylphosphine in
DMF at 25°C generates a 1,2-disubstituted allylic alcohol
regioselectively.
K. Takai, S. Sakamoto, T. Isshiki, Org. Lett., 2003, 5,
653-655.
A stereoselective multicomponent synthesis of (Z)-β-bromo
Baylis-Hillman ketones uses MgBr2 as both the Lewis acidic promoter
and the bromine source for the Michael-type addition with α,β-acetylenic ketones
to form an active β-bromo allenolate intermediate, which in turn attacks various
aldehydes to afford β-bromo Baylis-Hillman adducts in good yields and Z-selectivity.
H.-X. Wei, R. L. Jasoni, J. Hu, G. Li, P. W. Pare, Tetrahedron,
2004, 60, 10233-10237.
The samarium diiodide promoted addition of α-halo-α,β-unsaturated esters to
carbonyl compounds led to (Z)-2-(1-hydroxyalkyl)-2,3-alkenoates in
good yields and very high stereoselectivity. A mechanism is proposed to
explain this transformation.
J. M. Concellon, M. Huerta, J. Org. Chem., 2005,
70, 4714-4719.
A simple and highly stereoselective method has been developed for the
synthesis of (Z)-β-iodo Baylis-Hillman adducts using CeCl3·7H2O/NaI
as an inexpensive and readily available reagent system.
J. S. Yadav, B. V. S. Reddy, M. K. Gupta, B. Eeshwaraiah, Synthesis,
2005, 57-60.
A nickel(0) N-heterocyclic carbene complex-catalyzed coupling of α-silyloxy
aldehydes and alkynylsilanes provides an effective entry to various anti-1,2-diols
with excellent diastereoselectivity.
K. Sa-ei, J. Montgomery, Org. Lett.,
2006,
8, 4441-4443.
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.
| Related
|
