Metal-organocatalytic tandem azide addition/oxyamination of aldehydes for the enantioselective synthesis of β-amino α-hydroxy esters

Article abstract of DOI:10.1002/ejoc.201301915

The tandem reaction of α,β-unsaturated aldehydes with trimethylsilyl azide and 2,2,6,6-tetramethylpiperidin-1-yloxy in the presence of chiral amines and iron complexes as the catalysts in a one-pot reaction enantioselectively afforded β-azido α-oxyaminated aldehydes. Further synthetic modification of the product afforded β-amino α-hydroxy esters in good yields with good diastereo- and enantioselectivities.

Full text of DOI:10.1002/ejoc.201301915

SHORT COMMUNICATION
DOI: 10.1002/ejoc.201301915
Metal–Organocatalytic Tandem Azide Addition/Oxyamination of Aldehydes
for the Enantioselective Synthesis of β-Amino α-Hydroxy Esters
Pranab K. Shyam[a] and Hye-Young Jang*[a,b]
Keywords: Organocatalysis / Radicals / Aldehydes / Azides / Iron
The tandem reaction of α,β-unsaturated aldehydes with tri-
methylsilyl azide and 2,2,6,6-tetramethylpiperidin-1-yloxy in
the presence of chiral amines and iron complexes as the cata-
lysts in a one-pot reaction enantioselectively afforded β-azido
α-oxyaminated aldehydes. Further synthetic modification of
the product afforded β-amino α-hydroxy esters in good yields
with good diastereo- and enantioselectivities.
Introduction
A tremendous amount of effort has been devoted to de-
veloping synthetic methods for optically active α-, β-, and
γ-amino aldehydes and their derivatives, such as amino
acids, owing to their broad utility in natural product synthe-
sis and in the pharmaceutical industries.[1,2] In particular,
the chiral amine catalyzed synthesis of amino aldehydes has
received great attention, for which the direct and highly
enantioselective addition of an amine group at different po-
sitions of an aldehyde has been made possible under envi-
ronmentally benign conditions (Scheme 1). Depending on
the catalytically competent species (enamine, iminium, or
dienamine), different amine sources have been used to af-
ford various amino aldehydes with good enantioselectivi-
ties.[3–5]
Among the organocatalyzed syntheses of amino alde-
hydes, the synthesis of β-amino aldehydes through the
Michael addition of a nitrogen nucleophile to an iminium
intermediate has attracted our interest, because we have
been involved in the study of asymmetric cascade organo-
catalytic reactions involving the iminium-catalyzed Michael
addition of various nucleophiles to α,β-unsaturated alde-
hydes.[6–8] The cascade reaction conditions involving
2,2,6,6-tetramethylpiperidinyloxy (TEMPO) and azide may
afford synthetically and pharmaceutically useful β-amino α-
hydroxy carbonyl compounds (Scheme 1),[9] which have
been synthesized by various methods,[10,11] for example, the
oxyamination of alkenes,[10] hydroxylation of β-amino enol-
ates,[11h] amination of keto esters,[11i] Henry reaction of
carbonyl compounds,[11j,11k,11l] Mannich reaction of α-oxy-
Scheme 1. Syntheses of amino aldehydes by organocatalysis.
aldehydes,[11m,11n] reduction of α-acetoxy-β-enamino es-
ters,[11o] and reduction of β-amino α-keto esters.[11p] In
comparison to the previously reported methods, the pro-
posed organocatalyzed tandem addition approach may af-
ford enantiomerically enriched β-amino α-hydroxy carbonyl
precursors from commercially available starting materials
with step economy without the use of expensive and highly
air- and moisture-sensitive metal complexes. In addition to
the synthesis of β-amino α-hydroxy carbonyl compounds,
β-azido α-oxyaminated aldehydes, formed from organocata-
lytic reactions, contain easily manipulated and versatile az-
[a] Division of Energy Systems Research, Ajou University
443749 Suwon, South Korea
E-mail: hyjang2@ajou.ac.kr
http://ajou.ac.kr/~hyjang2
[b] Korea Carbon Capture & Sequestration R&D Center,
Deajeon 305-343, Korea
Supporting information for this article is available on the
WWW under http://dx.doi.org/10.1002/ejoc.201301915.
Eur. J. Org. Chem. 2014, 1817–1822
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P. K. Shyam, H.-Y. Jang
SHORT COMMUNICATION
ide and aldehyde functional groups, which can be converted and metal catalysts.[14] As the azide source, trimethylsilyl
into various other functional groups. azide (TMSN3) was used along with benzoic acid to afford
Although the Michael addition of azides to ketones, es- HN3. Suitable metal catalysts for the addition of TEMPO
ters, carboxylic acids, amides, and electron-deficient nitro were investigated; the use of FeCl3·6H2O as the catalyst af-
compounds has been reported,[12] the Michael addition of forded 1b in good yield (Table 1, entry 2). To increase the
azides to α,β-unsaturated aldehydes has been rarely re- stereoselectivity of the reaction, the sterically bulky organo-
ported because of competitive 1,2-addition and the polyme- catalyst (R)-2-{bis[3,5-bis(trifluoromethyl)phenyl][(trimeth-
rization of aldehydes in the presence of nitrogen nucleo- ylsilyl)oxy]methyl}pyrrolidine (B) was used to afford 1b in
philes.[13] The catalytic version of the enantioselective higher yield and enantioselectivity (Table 1, entry 5). If the
Michael addition of azides to α,β-unsaturated aldehydes reaction temperature was lowered to –15 °C, the enantio-
has not been reported yet. In this study, the enantioselective selectivity slightly increased (Table 1, entry 6). Then, vari-
tandem iminium-catalyzed azide addition and enamine/ ous carboxylic acids, bases, and F– sources [CsF and tetra-
iron-catalyzed oxyamination of α,β-unsaturated aldehydes butylammonium fluoride (TBAF)] were investigated to gen-
afforded optically active α,β-disubstituted aldehydes, which erate the azide nucleophile (Table 1, entries 7–12). Tri-
were further modified to biologically important β-amino α- fluoroacetic acid (TFA) catalyzed the reaction to afford 1b
hydroxy esters.
with slightly lower diastereo- and enantioselectivity than
other acids and the base. CsF did not promote the reaction
at all, and TBAF induced the highest enantioselectivity, al-
beit in a low yield (3%). Upon screening the metal catalysts,
Results and Discussion
The asymmetric tandem addition of azide and TEMPO higher yields were obtained with the use of hydrated iron
to cinnamaldehyde (1a) was investigated in the presence of complexes. Therefore, water (1 equiv.) was added to the re-
(S)-2-[diphenyl(trimethylsilyloxy)methyl]pyrrolidine
(A) action mixture containing FeCl3·6H2O; however, a lower
Table 1. Optimization of the enantioselective tandem addition of azide and TEMPO to 1a.
[a] H2O (1 equiv.).
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Metal–Organocatalytic Tandem Azide Addition/Oxyaminations
yield and selectivity were obtained (Table 1, entry 13). In Table 2. Tandem addition of azide and TEMPO to α,β-unsaturated
carbonyl compounds.[a]
addition to catalysts A and B, diverse proline derivatives
(e.g., C, E, and F), proline (D), and imidazolidinone cata-
lysts (e.g., G and H) were investigated, all of which afforded
1b in low yields with low enantioselectivities (Table 1, en-
tries 14–19). Catalysts B, C, E, and F generated (2R,3R)-1b,
and catalysts A, D, G, and H afforded (2S,3S)-1b. More-
over, other solvents (THF, toluene, DMF, CHCl3, and
CH2Cl2) were used; however, 1b was formed in less than
5% yield (THF: 2%, toluene: 5%, DMF: 1%, CHCl3: 4%,
CH2Cl2: 3%). As an azido source, NaN3 was used instead
of TMSN3 under the optimized conditions, and desired tan-
dem addition product 1b was not isolated. Because this tan-
dem reaction comprises both Michael addition and oxyam-
ination, the formation of a simple azide addition product
from the simple Michael addition of 1a was attempted in
the absence of both TEMPO and the metal complex. In
the absence of only TEMPO, however, no simple Michael
addition product was isolated. Presumably, the azide ad-
dition product may not be stable under the asymmetric
iminium catalysis conditions, and thus no asymmetric azide
addition to the α,β-unsaturated aldehydes would occur, as
reported. Upon combining both the azide addition and
oxyamination protocols, α,β-unsaturated aldehyde 1a was
smoothly converted into 1b. Furthermore, chiral amine cat-
alysts and the stereocontrolled azido group at the β-posi-
tion cooperatively controlled the stereochemistry of the α-
position to afford 1b with excellent diastereo- and enantio-
selectivity.
Next, a diverse array of α,β-unsaturated aldehydes were
subjected to the optimized reaction conditions for the tan-
dem azide/TEMPO addition. As listed in Table 2, 4-bromo-
cinnamaldehyde (2a) was converted into 2b in 51% yield
with 84% enantiomeric excess (ee; Table 2, entry 1). The
transformation of 4-methylcinnamaldehyde (3a) into 3b re-
sulted in a yield and enantioselectivity that was similar to
that obtained with 1b (Table 2, entry 2). Relative to the
enantioselectivity obtained with para-substituted cinnamal-
dehyde derivatives, the reaction of ortho-methoxycinnamal-
dehyde (4a) resulted in slightly reduced enantioselectivity
(Table 2, entry 3). The reactions of naphthalene- and
dichlorophenyl-substituted aldehydes 5a and 6a afforded 5b
and 6b in 49% yield (80% ee) and 59% yield (82%ee),
respectively (Table 2, entries 4 and 5). The reaction of thio-
phenyl aldehyde 7a afforded 7b in 45% yield with the high-
[a] Reaction conditions: aldehyde (0.25 mmol) was added to a solu-
est enantioselectivity (90%ee; Table 2, entry 6). The reac-
tion of cyclopropyl-substituted aldehyde 8a resulted in a
lower yield and a lower enantioselectivity relative to that of
the aromatic substituted aldehydes (Table 2, entry 7).
Methyl vinyl ketone (9a) was subjected to the reaction con-
ditions to afford 9b in 60% yield; however, no enantio-
tion of (R)-2-[bis(3,5-bis(trifluoromethyl)phenyl(trimethylsilyloxy)-
methyl]pyrrolidine (20 mol%), FeCl3·6H2O (10 mol%), benzoic acid
(0.5 mmol), TMSN3 (0.5 mmol), and TEMPO (0.5 mmol) in
CH3CN. The reaction mixture was stirred in the air at –15 °C for
20 h.
selectivity was achieved. In the reaction of 9a, chiral cata- sponding esters successfully afforded 1c and 1cЈ in 80 and
lyst B was not involved in the oxyamination step. Instead, 62% yield, respectively. A combination of zinc metal (Zn)
an enol intermediate that was formed by the reaction of the and acetic acid was used to cleave the O–N bond of
ketone with the acid reacted with the Fe–TEMPO complex. TEMPO. To our delight, cleavage of the O–N bond and
The utility of our protocol was shown by the synthesis azide reduction occurred simultaneously to afford β-amino
of optically active β-amino α-hydroxy esters from 1b α-hydroxy esters 1d and 1dЈ in 50 and 51% yield, respec-
(Scheme 2). The conversion of aldehyde 1b into the corre- tively. The absolute and relative stereochemistry of 1dЈ was
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P. K. Shyam, H.-Y. Jang
SHORT COMMUNICATION
established by comparing its optical rotation and 1H NMR oxidants. The mechanism involving the participation of
spectroscopic data with the reported data.[11p] The enantio- azido radicals generated from TMSN3 and TEMPO was
selectivity of 1d and 1dЈ was measured by HPLC analysis, also considered.[16] However, in the absence of metal cata-
which indicated no decrease in the enantioselectivity during lysts, the reaction did not proceed, and this indicates that
the synthetic modification of 1b.
this reaction cannot occur through a simple radical process.
Conclusions
Herein, we reported a tandem reaction involving the im-
inium-catalyzed Michael addition of azides and the iron-
catalyzed TEMPO addition to α,β-unsaturated aldehydes.
A diverse array of β-azido α-oxyaminated aldehydes were
prepared in good yields with good diastereo- and enantio-
selectivities under environmentally benign conditions. Fur-
ther synthetic modification of the product afforded β-amino
α-hydroxy esters from easily accessible reactants in four
steps. The potential application of this protocol for the syn-
theses of biologically and pharmaceutically important
building blocks was demonstrated. In addition, we showed
for the first time that azide nucleophiles can be used in the
chiral amine catalyzed Michael addition of α,β-unsaturated
aldehydes. Problems associated with the Michael addition
of azides to α,β-unsaturated aldehydes were solved by a tan-
dem reaction protocol. Subsequent organocatalyzed α-oxy-
amination of β-azido aldehydes solved the problems related
to azide addition to α,β-unsaturated aldehydes.
Scheme 2. Synthesis of β-amino α-hydroxy esters; DIC = N,NЈ-di-
isopropylcarbodiimide, DMAP = 4-(dimethylamino)pyridine.
A reaction mechanism for the tandem addition of azide
and TEMPO to α,β-unsaturated aldehydes is proposed, as
shown in Scheme 3. It comprises two catalytic cycles: (1) a
catalytic cycle for the iminium-mediated azide addition and
(2) a cycle for the enamine-mediated TEMPO addition. The
first catalytic cycle begins with the formation of iminium
salt I from cinnamaldehyde and catalyst B. The subsequent
Michael addition of an azide nucleophile to iminium I af-
Experimental Section
fords enamine intermediate II, which undergoes FeIII
–
General: Anhydrous solvents were transferred by an oven-dried sy-
TEMPO addition. The presence of a FeIII–TEMPO com-
plex was proposed in the FeIII-complex-catalyzed α-oxy-
amination of aldehydes.[15] The reduced FeII species is then
oxidized by TEMPO or oxygen and adds to the catalytic
cycle. Because the reaction runs in air and uses 3 equiv. of
TEMPO, the oxidation of FeII to FeIII is possible by both
ringe. Dichloromethane was distilled from calcium hydride. 1H
NMR spectra were recorded with
a Varian Mercury plus
(400 MHz) spectrometer. Chemical shifts are reported in delta (δ)
units, parts per million (ppm) downfield from tetramethylsilane.
13C NMR spectra were recorded with a Varian Mercury plus
(100 MHz) spectrometer. Chemical shifts are reported in delta (δ)
units, parts per million (ppm) relative to the center of the triplet at δ
= 77.00 ppm for deuteriochloroform. TEMPO and the chiral amine
catalysts were purchased from Aldrich, and FeCl3·6H2O was pur-
chased from Kanto Chemical (97.0% purity). These chemicals were
used without purification.
General Procedure for the Catalytic Reaction: A mixture of alde-
hyde (0.25 mmol), trimethylsilyl azide (0.50 mmol), benzoic acid
(0.50 mmol), TEMPO (0.75 mmol), FeCl3·6H2O (0.025 mmol), and
(R)-α,α-bis[3,5-bis(trifluoromethyl)phenyl]-2-pyrrolidinemethanol
trimethylsilyl ether (0.05 mmol) in CH3CN (0.625 mL) was stirred
in the air at –15 °C for 16–22 h. The solvent was removed under
reduced pressure to produce a residue that was purified by column
chromatography on a silica gel (hexane/diethyl ether = 99:1) to ob-
tain the final pure product.
Supporting Information (see footnote on the first page of this arti-
cle): Experimental procedures and 1H NMR and 13C NMR spectra
Acknowledgments
This study was supported by the Korea Research Foundation
(grant numbers 2009-0094046 and 2013008819) and a Korea CCS
R&D Center (KCRC) grant from the Korea Government, Ministry
of Education, Science and Technology (grant number 2012-
0008935).
Scheme 3. A plausible reaction mechanism.
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Metal–Organocatalytic Tandem Azide Addition/Oxyaminations
McQuade, J. Am. Chem. Soc. 2007, 129, 9216–9221; c) B. Sim-
mons, A. M. Walji, D. W. C. MacMillan, Angew. Chem. Int.
Ed. 2009, 48, 4349–4353; Angew. Chem. 2009, 121, 4413–4417;
d) S. Chercheja, S. K. Nadakudity, P. Eilbracht, Adv. Synth.
Catal. 2010, 352, 637–643; e) A. Quintard, A. Alexakis, Adv.
Synth. Catal. 2010, 352, 1856–1860; f) S. Lin, G.-L. Zhao, L.
Deiana, J. Sun, Q. Zhang, H. Leijonmarck, A. Córdova, Chem.
Eur. J. 2010, 16, 13930–13934; g) A. Quintard, A. Alexakis, C.
Mazet, Angew. Chem. Int. Ed. 2011, 50, 2354–2358; Angew.
Chem. 2011, 123, 2402–2406; h) M. Rueping, H. Sundén, L.
Hubener, E. Sugiono, Chem. Commun. 2012, 48, 2201–2203; i)
Z. Shao, H. Zhang, Chem. Soc. Rev. 2009, 38, 2745–2755; j) C.
Zhong, X. Shi, Eur. J. Org. Chem. 2010, 2999–3025; k) Z. Du,
Z. Shao, Chem. Soc. Rev. 2013, 42, 1337–1378.
For asymmetric cascade organocatalytic reactions involving the
iminium-catalyzed Michael addition of malonate to α,β-unsat-
urated aldehydes, see: a) H.-S. Yoon, X.-H. Ho, J. Jang, H.-J.
Lee, S.-J. Kim, H.-Y. Jang, Org. Lett. 2012, 14, 3272–3275; b)
X.-H. Ho, H.-J. Oh, H.-Y. Jang, Eur. J. Org. Chem. 2012, 5655–
5659; for asymmetric cascade organocatalytic reactions involv-
ing the iminium-catalyzed Michael addition of malonate and
nitromethane to α,β-unsaturated aldehydes, see: c) J.-H. Kim,
E.-J. Park, H.-J. Lee, X.-H. Ho, H.-S. Yoon, P. Kim, H. Yun,
H.-Y. Jang, Eur. J. Org. Chem. 2013, 4337–4344.
[1]
For reviews on the synthesis of β-amino acids, see: a) D. C.
Cole, Tetrahedron 1994, 50, 9517–9582; b) E. Juaristi, D. Quin-
tana, J. Escalante, Aldrichim. Acta 1994, 27, 3–11; c) J.-A. Ma,
Angew. Chem. Int. Ed. 2003, 42, 4290–4299; Angew. Chem.
2003, 115, 4426–4435; d) M. Liu, M. P. Sibi, Tetrahedron 2002,
58, 7991; e) E. Juaristi, V. A. Soloshonok, Enantioselective Syn-
thesis of β-Amino Acids, 2nd ed., John Wiley & Sons, Hoboken,
2005; f) D. Seebach, A. K. Beck, S. Capone, G. Deniau, U.
Grosˇelj, E. Zass, Synthesis 2009, 1–31; g) B. Weiner, W. Szym-
an´ski, D. B. Janssen, A. J. Minnaard, B. L. Feringa, Chem. Soc.
Rev. 2010, 39, 1656–1691.
For reviews on the synthesis of α- and γ-amino acids, see: a)
M. J. O’Donnell, Acc. Chem. Res. 2004, 37, 506–517; b) C.
Nájera, J. M. Sasano, Chem. Rev. 2007, 107, 4584–4671; c) M.
Ordónez, C. Cativiela, Tetrahedron: Asymmetry 2007, 18, 3–99.
For recent aminocatalysis reviews, see: a) A. Berkessel, H.
Gröger, Asymmetric Organocatalysis, Wiley-VCH, Weinheim,
Germany, 2005; b) G. Lelais, D. W. C. MacMillan, Aldrichim.
Acta 2006, 39, 79–87; c) M. Marigo, K. A. Jørgensen, Chem.
Commun. 2006, 2001–2011; d) N. Marion, D. González, S. P.
Nolan, Angew. Chem. Int. Ed. 2007, 46, 2988–3000; Angew.
Chem. 2007, 119, 3046–3058; e) B. List, Chem. Rev. 2007, 107,
5413–5415; f) A. Erkkilä, I. Majander, P. M. Pihko, Chem. Rev.
2007, 107, 5416–5470; g) S. Mukherjee, J. W. Yang, S.
Hoffmannm, B. List, Chem. Rev. 2007, 107, 5471–5569; h) T.
Hashimoto, K. Maruoka, Chem. Rev. 2007, 107, 5656–5682; i)
L.-W. Ye, I. Zhou, Y. Tang, Chem. Soc. Rev. 2008, 37, 1140–
1152; j) P. Melchiorre, M. Marigo, A. Carlone, G. Bartoli, An-
gew. Chem. Int. Ed. 2008, 47, 6138–6171; Angew. Chem. 2008,
120, 6232–6265; k) L.-W. Xu, J. Luo, Y. Lu, Chem. Commun.
2009, 1807–1821; l) C. Palomo, M. Oiarbide, R. López, Chem.
Soc. Rev. 2009, 38, 632–653.
[2]
[3]
[8]
[9]
a) C. S. Swindell, N. E. Krauss, S. B. Horwitz, I. Ringel, J.
Med. Chem. 1991, 34, 1176–1184; b) D. Guénard, F. Guéritte-
Voegelein, P. Potier, Acc. Chem. Res. 1993, 26, 160–167; c)
M. L. Miller, I. Ojima, Chem. Rec. 2001, 1, 195–211; d) D. G. I.
Kinston, Chem. Commun. 2001, 867–880; e) A. Madhan, A. R.
Kumar, B. V. Rao, Tetrahedron: Asymmetry 2001, 12, 2009–
2011; f) S. B. Horwitz, J. Nat. Prod. 2004, 67, 136–138; g) S.-
y. Tosaki, R. Tsuji, T. Ohshima, M. Shibasaki, J. Am. Chem.
Soc. 2005, 127, 2147–2155.
[10]
[11]
[4]
For selected articles on Sharpless reactions, see: a) K. B.
Sharpless, A. O. Chong, K. Oshima, J. Org. Chem. 1976, 41,
177–179; b) E. Herranz, K. B. Sharpless, J. Org. Chem. 1978,
43, 2544–2548; c) G. Li, H.-T. Chang, K. B. Sharpless, Angew.
Chem. Int. Ed. Engl. 1996, 35, 451–454; Angew. Chem. 1996,
108, 449–452; d) P. O’Brien, Angew. Chem. Int. Ed. 1999, 38,
326–329; Angew. Chem. 1999, 111, 339; e) L. Harris, S. P. H.
Mee, R. H. Furneaux, G. J. Gainsford, A. Luxenburger, J. Org.
Chem. 2011, 76, 358–372.
For reviews on iminium catalysis, see: a) H.-C. Guo, J.-A. Ma,
Angew. Chem. Int. Ed. 2006, 45, 354–366; Angew. Chem. 2006,
118, 362–375; b) G. Lelais, D. W. C. MacMillan, Aldrichim.
Acta 2006, 39, 79–87; c) B. List, Chem. Commun. 2006, 819–
824; d) C. Palomo, A. Mielgo, Angew. Chem. Int. Ed. 2006, 45,
7876–7880; Angew. Chem. 2006, 118, 8042–8046; e) M. J.
Gaunt, C. C. C. Johansson, A. McNally, N. T. Vo, Drug Dis-
covery Today 2007, 12, 8–27; f) D. Enders, C. Grondal,
M. R. M. Hüttl, Angew. Chem. Int. Ed. 2007, 46, 1570–1581;
Angew. Chem. 2007, 119, 1590–1601; g) D. Almasi, D. A.
Alonso, C. Nájera, Tetrahedron: Asymmetry 2007, 18, 299–365;
h) Y. Zhang, W. Wang, Catal. Sci. Technol. 2012, 2, 42–53.
For selective articles on dienamine catalysis, see: a) C. Appayee,
A. J. Fraboni, S. E. Brenner-Moyer, J. Org. Chem. 2012, 77,
8828–8834; b) M. Ikeda, Y. Miyake, Y. Nishibayashi, Organo-
metallics 2012, 31, 3810–3813; c) J. Stiller, E. Marqués-López,
R. P. Herrera, R. Fröhlich, C. Strohmann, M. Christmann,
Org. Lett. 2011, 13, 70–73; d) S. Bertelsen, M. Marigo, S.
Brandes, P. Dinér, K. A. Jørgensen, J. Am. Chem. Soc. 2006,
128, 12973–12980.
For reviews on organocatalytic domino reactions, see: a) B.
List, Chem. Commun. 2006, 819–824; b) D. Enders, C. Gron-
dal, M. R. M. Hüttl, Angew. Chem. Int. Ed. 2007, 46, 1570–
1581; Angew. Chem. 2007, 119, 1590–1601; c) S. B. Tsogoeva,
Eur. J. Org. Chem. 2007, 1701–1716; d) X. Yu, W. Wang, Org.
Biomol. Chem. 2008, 6, 2037–2046; e) A. Dondoni, A. Massi,
Angew. Chem. Int. Ed. 2008, 47, 4638–4660; Angew. Chem.
2008, 120, 4716–4739; f) J. Zhou, Chem. Asian J. 2010, 5, 422–
434; g) B. Westermann, M. Ayaz, S. S. van Berkel, Angew.
Chem. Int. Ed. 2010, 49, 846–849; Angew. Chem. 2010, 122,
858–861; h) H. Pellissier, Adv. Synth. Catal. 2012, 354, 237–
294; i) R. C. Wende, P. R. Schreiner, Green Chem. 2012, 14,
1821–1849.
For selected articles on the synthesis of β-amino α-hydroxy
carbonyl compounds, see: a) W. H. Pearson, J. V. Hines, J. Org.
Chem. 1989, 54, 4235–4237; b) S. C. Bergmeier, D. M. Stanch-
ina, J. Org. Chem. 1999, 64, 2852–2859; c) J. E. Semple, T. D.
Owens, K. Nguyen, O. E. Levy, Org. Lett. 2000, 2, 2769–2772;
d) Y. Aoyagi, R. P. Jain, R. M. Williams, J. Am. Chem. Soc.
2001, 123, 3472–3477; e) S. Raghavan, M. A. Rasheed, Tetrahe-
dron: Asymmetry 2003, 14, 1371–1374; f) D. Uraguchi, K. Sori-
machi, M. Terada, J. Am. Chem. Soc. 2005, 127, 9360–9361; g)
J. A. R. Rodrigues, H. M. S. Milagre, C. D. F. Milafre, P. J. S.
Moran, Tetrahedron: Asymmetry 2005, 16, 3099–3106; h) M. E.
Bunnage, A. N. Chernega, S. G. Davies, C. J. Goodwin, J.
Chem. Soc. Perkin Trans. 1 1994, 2373–2384; i) K. Juhi, K. A.
Jørgensen, J. Am. Chem. Soc. 2002, 124, 2420–2421; j) I. Kud-
yba, J. Raczko, J. Jurczak, J. Org. Chem. 2004, 69, 2844–2850;
k) J. C. Borah, S. Gogoi, J. Boruwa, B. Kalita, N. C. Barua,
Tetrahedron Lett. 2004, 45, 3689–3691; l) N. Gogoi, J. Boruwa,
N. C. Barua, Tetrahedron Lett. 2005, 46, 7581–7582; m) P.
Dziedzic, P. Schyman, M. Kullberg, A. Córdova, Chem. Eur.
J. 2009, 15, 4044–4048; n) P. Dziedzic, J. Vesely, A. Córdova,
Tetrahedron Lett. 2008, 49, 6631–6634; o) Y. Jiang, X. Chen,
Y. Zheng, Z. Xue, C. Shu, W. Yuan, X. Zhang, Angew. Chem.
Int. Ed. 2011, 50, 7304–7307; Angew. Chem. 2011, 123, 7442–
7445; p) C. G. Goodman, D. T. Do, J. S. Johnson, Org. Lett.
2013, 15, 2446–2449.
[5]
[6]
[7]
For selected recent reviews and articles on tandem organocata-
lytic reactions with the use of transition-metal complexes, see:
a) S. L. Poe, M. Kobasˇlija, D. T. McQuade, J. Am. Chem. Soc.
2006, 128, 15586–15587; b) S. L. Poe, M. Kobasˇlija, D. T.
[12]
a) D. J. Guerin, T. E. Horstmann, S. J. Miller, Org. Lett. 1999,
1, 1107–1109; b) J. K. Myers, E. N. Jacobsen, J. Am. Chem.
Soc. 1999, 121, 8959–8960; c) T. E. Horstmann, D. J. Guerin,
Eur. J. Org. Chem. 2014, 1817–1822
© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
1821

P. K. Shyam, H.-Y. Jang
SHORT COMMUNICATION
S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635–3658; Angew.
Chem. 2000, 112, 3781–3784; d) L.-W. Xu, L. Li, C.-G. Xia,
S.-L. Zhou, J.-W. Li, Tetrahedron Lett. 2004, 45, 1219–1221; e)
D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134–
2136; f) I. Adamo, F. Benedetti, F. Berti, P. Campamer, Org.
Lett. 2006, 8, 51–54; g) M. Nielsen, W. Zhuang, K. A.
Jørgensen, Tetrahedron 2007, 63, 5849–5854; h) T. Angelini, S.
Bonollo, D. Lanari, F. Pizzo, L. Vaccaro, Org. Lett. 2012, 14,
4610–4613.
Kudo, Chem. Commun. 2010, 46, 8040–8042; c) J. F. Van Hum-
beck, S. P. Simonovich, R. R. Knowles, D. W. C. MacMillan,
J. Am. Chem. Soc. 2010, 132, 10012–10014; d) T. Kano, H.
Mii, K. Maruoka, Angew. Chem. Int. Ed. 2010, 49, 6638–6641;
Angew. Chem. 2010, 122, 6788–6791; e) S. P. Simonovich, J. F.
Van Humbeck, D. W. C. MacMillan, Chem. Sci. 2012, 3, 58–
61.
[15]
J. F. Van Humbeck, S. P. Simonovich, R. R. Knowles, D. W. C.
MacMillan, J. Am. Chem. Soc. 2010, 132, 10012–10014.
[13] a) J. Wengel, J. Lau, E. B. Pedersen, C. M. Nielsen, J. Org.
Chem. 1991, 56, 3591–3594; b) C. Gauthier, Y. Ramondenc, G.
Plé, Tetrahedron 2001, 57, 7513–7517; c) S.-G. Kim, T.-H. Park,
Synth. Commun. 2007, 37, 1027–1035.
[14] a) M. P. Sibi, M. Hasegawa, J. Am. Chem. Soc. 2007, 129,
4124–4125; b) K. Akagawa, T. Fujiwara, S. Sakamoto, K.
[16] a) H. Miyazoe, S. Yamago, J.-i. Yoshida, Angew. Chem. Int. Ed.
2000, 39, 3669–3671; Angew. Chem. 2000, 112, 3815–3817; b)
T. Wang, M. Jiao, J. Am. Chem. Soc. 2013, 135, 11692–11695.
Received: December 24, 2013
Published Online: January 29, 2014
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© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2014, 1817–1822