Phase-transfer enantioselective monoalkylation of prochiral nickel(ii) complexes catalyzed by 3,3′-bis[hydroxy(diphenyl)methyl]-1,1′- binaphthyl-2,23′-diol (BIMBOL) as a route to α-amino acids

Article abstract of DOI:10.1007/s11172-012-0329-6

An achiral nickel complex with a Schiff base derived from glycine was alkylated with alkyl halides under conditions of asymmetric phase-transfer catalysis. The chiral tetraol (R)-BIMBOL was employed as a catalyst. The enantiomeric purity of the alkylation products was up to 88%. Subsequent decomposition of the complexes afforded the corresponding a-amino acids.

Full text of DOI:10.1007/s11172-012-0329-6

Russian Chemical Bulletin, International Edition, Vol. 61, No. 12, pp. 2344—2349, December, 2012
2344
Phaseꢀtransfer enantioselective monoalkylation of prochiral
nickel(II) complexes catalyzed by 3,3´ꢀbis[hydroxy(diphenyl)methyl]ꢀ
1,1´ꢀbinaphthylꢀ2,2´ꢀdiol (BIMBOL) as a route to ꢀamino acids
Yu. N. Belokon,a V. I. Maleev,a Yu. V. Samoilichenko,a M. A. Moskalenko,a K. V. Hakobyan,b and A. S. Saghyanb
aA. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences,
28 ul. Vavilova, 119991 Moscow, Russian Federation.
Fax: +7 (499) 135 5085. Eꢀmail: yubel@ineos.ac.ru
bDepartment of Chemistry, Yerevan State University,
1 ul. Manoogiana, 0025 Yerevan, Republic of Armenia
An achiral nickel complex with a Schiff base derived from glycine was alkylated with
alkyl halides under conditions of asymmetric phaseꢀtransfer catalysis. The chiral tetraol
(R)ꢀBIMBOL was employed as a catalyst. The enantiomeric purity of the alkylation prodꢀ
ucts was up to 88%. Subsequent decomposition of the complexes afforded the corresponding
ꢀamino acids.
Key words: phaseꢀtransfer asymmetric catalysis, ꢀamino acids, nickel complexes, alkylation.
Enantiomerically pure ꢀamino acids, especially nonꢀ
proteinogenic ones, are frequently used as building blocks
for designing important medicines and modern antibiotꢀ
ics1,2 as well as modified enzymes and peptides.3,4 In the
last few years, they have also served as chiral catalysts for
asymmetric synthesis.5 Catalytic asymmetric synthesis has
important advantages over other routes to amino acids6
such as (1) the possibility of preparing nonꢀproteinogenic
and/or Dꢀamino acids and (2) formation of large amounts
of an enantioenriched product from a racemic or achiral
starting material through the use of small amounts of
a chiral catalyst.
Schiff bases derived from alanine esters (Scheme 1) in the
presence of solid NaOH. Based on the results obtained,
we have developed a method of asymmetric synthesis of
quaternary amino acids with considerable asymmetric inꢀ
duction.19 This catalyst acts by transforming TADDOL
into a conjugated alkoxide base that is soluble in the orꢀ
ganic phase. The driving force of the process is the reacꢀ
tion of the base with a CH acid (Schiff base of alanine)
followed by alkylation of an intermediate carbanion in
a complex with TADDOL. Application of this approach
to the synthesis of amino acids containing an acidic
ꢀproton failed because the conjugated TADDOL base
was very strong and the final product underwent in situ
racemization.
Because of this, it is currently important to develop
efficient methods for catalytic asymmetric synthesis of
amino acids.6—11
Among the merits of phaseꢀtransfer asymmetric catalꢀ
ysis are feasible procedures, mild reaction conditions,
inexpensive starting reagents and solvents, and the possiꢀ
bility of easily scaling the synthesis.12
Scheme 1
Phaseꢀtransfer asymmetric catalytic ꢀalkylation of
prochiral glycine synthons is a very attractive approach to
the synthesis of enantioenriched ꢀamino acids.13 Most of
the phaseꢀtransfer catalysts employed earlier for this purꢀ
pose belong to the alkaloid cinchonine derivatives.12 They
are difficult to modify rationally and this is a serious drawꢀ
back precluding "fine tuning" of the catalyst to various
substrates needed to achieve reasonable reactivity and seꢀ
lectivity.14—18
R = Me, X = H; R = Pri, X = H; R = Pri, X = Cl; R = Pri, X = F;
R = But, X = H
R´= Bn, allyl, ꢀnaphthylmethyl; Y = Br, Cl
Earlier, we have demonstrated that ,,´,´ꢀtetraꢀ
arylꢀ1,3ꢀdioxolaneꢀ4,5ꢀdiyldimethanol (TADDOL) effiꢀ
ciently catalyzes phaseꢀtransfer asymmetric alkylation of
Recently, we have found that the use of salts of (R)ꢀ or
(S)ꢀ3,3´ꢀbis[hydroxy(diphenyl)methyl]ꢀ1,1´ꢀbinaphthylꢀ
2,2´ꢀdiol (BIMBOL) as phaseꢀtransfer catalysts for enanꢀ
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2322—2327, December, 2012.
1066ꢀ5285/12/6112ꢀ2344 © 2012 Springer Science+Business Media, Inc.

BIMBOLꢀcatalyzed alkylation of nickel(II) complexes Russ.Chem.Bull., Int.Ed., Vol. 61, No. 12, December, 2012
2345
Table 1. Efficiency—structure relationship for the catalyst in the
monoalkylation of complex 1 with benzyl bromide
Entry Catalyst
B
t/min
Y (%)
eeb (%)
1
2
3
4
5
6
7
(R)ꢀTADDOL NaOH
(R)ꢀTADDOL NaOH
10
60
60
60
60
60
60
10
30
14
65
75
85
67
12 (R)
0
17 (R)
9 (S)
0
(S)ꢀBINOL
(R)ꢀBIMBOL
NaOH
NaOH
(R)ꢀTADDOL KOH
(R)ꢀBINOL
(R)ꢀBIMBOL
KOH
KOH
16 (S)
50 (S)
Note. B is the base used, t is the reaction time, and Y is the yield.
a Reaction conditions: ~20 C, CH2Cl2, 10 mol.% catalyst,
NaOH (10 equiv.) or KOH (2.5 equiv.), benzyl bromide
(1.2 equiv. with respect to 1).
b ee of the corresponding phenylalanine was determined by GLC
on a chiral column.
dling these substances. Third, all the resulting enantioꢀ
enriched alkylation products have high specific rotation
and hence their enantiomeric purity can be determined
much more easily.21
tioselective Michael addition involving nickel complexes
with Schiff bases derived from glycine (1) and dehydroꢀ
alanine (2) affords glutamic acid derivatives with no apꢀ
preciable racemization.20
Results and Discussion
It was interesting to extend the scope of this system by
applying it to phaseꢀtransfer alkylation for the synthesis of
amino acids containing an acidic ꢀproton. BIMBOL itself
can easily be prepared from commercial BINOL.
Here we describe phaseꢀtransfer alkylation of achiral
nickel complex 1 with BIMBOL as a catalyst.
The use of an achiral nickel complex with a glycine
derivative as a substrate provides a number of important
advantages. First, this complex can efficiently be coordiꢀ
nated with a chiral catalyst, thus predetermining the diꢀ
rection of an attack of an alkylating agent on the glycine
moiety. Second, both the starting complex and the alkylaꢀ
tion product are brightly colored, which facilitates hanꢀ
The catalytic efficiencies of TADDOL, BINOL, and
(R)ꢀBIMBOL in the alkylation of complex 1 with benzyl
bromide as an example (Scheme 2) under conditions of
phaseꢀtransfer catalysis are compared in Table 1.
It can be seen that (R)ꢀTADDOL favors rapid racemꢀ
ization of the alkylation product (see Table 1, entries 1, 2,
and 5). BINOL is highly efficient only with KOH as a base;
however, the ee of the product is 16% only (see Table 1,
entries 3 and 6). (R)ꢀBIMBOL actively catalyzes the
alkylation reaction in the presence of both KOH and
NaOH (see Table 1, entries 4 and 7). However, the enanꢀ
tiomeric purity of the product was measurable (50%) only
when KOH was used (see Table 1, entry 7). Thus, the
Scheme 2
X = Br, I; R = All (3), Bn (4), 4ꢀFꢀBn (5), 4ꢀIꢀBn (6), 4ꢀNO2ꢀBn (7), C2H5 (8), All (9)
Reagents and conditions: i. RX (2 equiv.); (R)ꢀBIMBOL (10 mol.%); CH2Cl2; base; 20 °C.

2346
Russ.Chem.Bull., Int.Ed., Vol. 61, No. 12, December, 2012
Belokon et al.
catalyst containing four OH groups (BIMBOL) is highly
active and provides higher enantioselectivity than do the
aforementioned diols.
Further, we studied alkylation of complex 1 with alkyl
halides in the presence of (R)ꢀBIMBOL under various
conditions; no dialkylation products were detected. This
is due to a lower C—H acidity of the amino acid moiety in
the monoalkylated complex and the steric hindrances to
an attack of a second alkylating agent.21
To optimize the reaction conditions, we alkylated comꢀ
plex 1 with allyl bromide in the presence of a number of
alkali metal hydroxides; other variables included the solꢀ
vent and the concentrations of the starting reagents. The
results obtained are summarized in Table 2.
As expected, the reaction does not occur when no base
is used (see Table 2, entry 1). With a strong base, BunLi,
the alkylation proceeds rapidly, although with no asymꢀ
metric induction (see Table 2, entry 2). With weaker bases
(alkali metal hydroxides), the enantioselectivy of the reacꢀ
tion substantially depends on the metal ion used. The enanꢀ
tiomeric purity of the product is unsatisfactory with NaOH
as a base (see Table 2, entries 3, 4). For other alkali metꢀ
als, ee decreases in the order: K > Cs > Rb (see Table 2,
entries 6, 10, 11).
entry 5), while addition of water (e.g., the use of 50%
aqueous KOH) blocks the reaction so that no alkylation
product is formed even in four hours (see Table 2, entry 9).
Even a small amount of water added to the reaction mixture
decreases the reaction rate, probably because of hydrolysis
of (R)ꢀBIMBOL phenolate, an actual catalytic species.
A similar effect of water has been noted in the study of phaseꢀ
transfer alkylation with TADDOL as a catalyst.19
An increase in either the amount of the base or the
reaction time (see Table 2, entries 7, 8) results in the forꢀ
mation of alkylation products with lower enantiomeric
purity, which can be attributed to promotion of racemizaꢀ
tion as a side process.
The choice of solvent is also crucial since the alkylaꢀ
tion reaction gives good results only in anhydrous CH2Cl2
(see Table 2, entries 12—14).
Alkylation with other alkylating agents was carried out
under the optimized reaction conditions (see Table 2, enꢀ
try 6). The data obtained are given in Table 3.
The use of (R)ꢀBIMBOL affords an (S)ꢀproduct. With
(S)ꢀBIMBOL, as expected, an (R)ꢀproduct is formed (see
Table 3, entry 2). Thus, by employing the catalytic system
described above (note that both BIMBOL enantiomers
are equally accessible), one can obtain amino acids of
both (R)ꢀ and (S)ꢀconfigurations.
The presence of water in the reaction mixture is also
crucial. Alkylation in anhydrous CH2Cl2 with anhydrous
KOH as a base affords a product with ee 88% (see Table 2,
The reaction mechanism is similar to that proposed
earlier for the catalysis with TADDOL19 and involves the
Table 2. (R)ꢀBIMBOLꢀcatalyzed monoalkylation of complex 1 with allyl bromidea
25
Entry
B (equiv.)
Solvent
t/min
Y (%)
[]D
ee (%)
1
2
3
4
5b,c
6c
7c
8
—
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
THF
120
20
120
60
120
60
60
120
240
60
0
80
15
70
30
60
60
70
0
70
80
30
10
30
—
0
+64
0
+2902
+2682
+2481
+1909
—
+1262
+1134
+56
ꢀ
0
2(S)
0
88(S)
81(S)
75(S)
58(S)
—
38(S)
34(S)
2(S)
—
BunLi (1)
NaOH (1)
NaOH (10)
KOH (1.5)
KOH (2.5)
KOH (3)
KOH (3)
9
50% aqueous KOH
CsOH•H2O (2.5)
RbOH (2.5)
KOH (1.5)
KOH (1.5)
KOH (1.5)
10
11
12
13
14
60
120
120
120
PhMe
MeCN
—
+120
4(S)
Note. B is the base used, t is the reaction time, and Y is the yield.
a (R)ꢀBIMBOL (10 mol.%) and an excess of allyl bromide (2 equiv.) with respect to complex 1 were used.
b An excess of allyl bromide (1.2 equiv.) was used with respect to complex 1.
c In entries 5—7, first the specific rotation angles of the complexes obtained were measured and then the correꢀ
sponding amino acids were isolated. Their enantiomeric purity was determined by GLC on a chiral phase. The ee of
the amino acid was plotted versus []D25 of the complex and the resulting plot was used to determine the enantioꢀ
25
meric purity of the products obtained in the other entries from []D without isolating the amino acid. For the
enantiomerically pure complex (S)ꢀ4, []D25 (CHCl3/MeOH) is 3306.

BIMBOLꢀcatalyzed alkylation of nickel(II) complexes Russ.Chem.Bull., Int.Ed., Vol. 61, No. 12, December, 2012
2347
Table 3. (R)ꢀBIMBOLꢀcatalyzed monoalkylation of complex 1a
[]D +109.8 (c 1.00, CHCl3) (cf. Ref. 23: []D +113.4
(c 1.00, CHCl3)), m.p. 186—188 C (cf. Ref. 24: m.p. 176—179 C).
1H NMR (CDCl3), : 4.79 (s, 2 H, OH); 6.70 (s, 2 H, OH);
7.14—7.17 (m, 2 H, Ar); 7.19 (s, 2 H, Ar); 7.28—7.40 (m, 24 H,
Ar), 7.65—7.68 (m, 2 H, Ar). Found (%): C, 79.2; H, 5.8.
C46H34O4•2H2O•Me2CO. Calculated (%): C, 78.9; H, 5.9.
(S)ꢀ3,3´ꢀBis[hydroxy(diphenyl)methyl]ꢀ1,1´ꢀbinaphthylꢀ2,2´ꢀ
diol ((S)ꢀBIMBOL) was prepared from (S)ꢀBINOL with
ee 99.9% (retention time 5.058 min) as described earlier;23
[]D25 –107.3 (c 1.00, CHCl3) (cf. Ref. 23: []D20 –109.5 (c 1.00,
CHCl3)).
25
20
25
Entry Product
Alkylating
t/min
Y
[]D
eeb
agent (equiv.)
(%)
(%)
1
2
3
4
5
6
3
AllBr (2)
BnBr (2)
4ꢀFꢀBnBr (2)
4ꢀIꢀBnBr (2)
4ꢀNO2ꢀBnBr (2)
C2H5I (3)
60
60
60
60
60
70 +2682 81 (S)
67 +1703 50 (S)
60 +2128 63 (S)
65 +1349 40 (S)
82 +974 29 (S)
20 +358 11 (S)
4c
5
6
7
8
240
The nickel(II) complex used as a substrate was synthesized
according to a known procedure.21 The 1H NMR spectra of the
complex obtained are identical with the literature data.21
(Nꢀ{Phenyl[2ꢀ(pyridineꢀ2ꢀcarboxamido)phenyl]methylꢀ
idene}glycinatoꢀN,N´,N´´,O)nickel(II) (complex 1), m.p. >280 C
(decomp.). 1H NMR (CDCl3), : 3.89 (s, 2 H, CH2); 6.84—6.89
(m, 1 H, Ar); 6.96—6.99 (m, 1 H, Ar); 7.16—7.18 (m, 2 H, Ar);
7.41—7.53 (m, 2 H, Ar); 7.60—7.62 (m, 3 H, Ar); 7.94—7.96
(m, 1 H, Ar); 8.03—8.08 (m, 1 H, Ar); 8.33—8.35 (m, 1 H, Ar);
9.03—9.06 (m, 1 H, Ar). Found (%): C, 60.58; H, 3.60; N, 10.05.
C21H15N3O3Ni. Calculated (%): C, 60.62; H, 3.63; N, 10.10.
Monoalkylation of complex 1 under the conditions of phaseꢀ
transfer catalysis (general procedure with allyl bromide as an exꢀ
ample). (R)ꢀBIMBOL (0.0047 g, 7.2•10–6 mol), freshly ground
KOH (0.010 g, 1.8•10–4 mol), and the starting complex 1 (0.03 g,
7.2•10–5 mol) were mixed in a roundꢀbottom flask filled with
argon. The mixture was dissolved with stirring in anhydrous
CH2Cl2 (1 mL). After 7—8 min, allyl bromide (0.012 mL,
1.44•10–4 mol) was added to the stirred mixture. The course of
the reaction was monitored by TLC (SiO2, CHCl3—Me2CO
(5 : 1) as an eluent). For all alkylated products, the Rf values are
close (0.45); for the starting complex 1, Rf is 0.09). After 1 h,
glacial AcOH (0.015 mL, 2.6•10–4 mol) was added and the reꢀ
action mixture was stirred for an additional 5—10 min and puriꢀ
fied by column chromatography on SiO2 with CHCl3—Me2CO
(5 : 1) as an eluent. The yield of product 3 was 70% (0.022 g,
5.04•10–5 mol).
Note. t is the reaction time and Y is the yield.
Reaction conditions: ~20 C, CH2Cl2, (R)ꢀBIMBOL
(10 mol.%), KOH (2.5 equiv. with respect to 1).
b The ee values of the amino acids obtained were determined by
GLC on a chiral phase.
c With (S)ꢀBIMBOL as a catalyst, the (R)ꢀenantiomer of the
product was obtained.
a
formation of BIMBOL phenolate on the surface of a solid
base. This chiral phenolate abstracts a proton from comꢀ
plex 1 to form neutral BIMBOL and the carbanion of
complex 1. The K+ ion and both the components are comꢀ
bined into a chiral complex as discussed earlier.20 The
phenyl substituent in the carbanion of complex 1 effects
chiral shielding of the glycine moiety. Subsequent alkylaꢀ
tion of the chiral carbanion leads to the formation of the
target product.
To sum up, BIMBOL is a an efficient catalyst for asymꢀ
metric phaseꢀtransfer alkylation. Our current investigaꢀ
tions pursue the use of this catalyst in various C—C bond
making reactions and its structural modification for
achieving better efficiency.
Experimental
During the alkylation reactions, a small amount of dinuclear
complex 10 was detected. This complex25 is produced by a side
reaction involving oxidation of the starting reagent 1 in the presꢀ
ence of oxygen and a base.25 To avoid the formation of this byꢀ
product, the dried solvent was degassed by a freeze—thaw proceꢀ
dure in vacuo (this procedure serves to remove oxygen and, acꢀ
cordingly, prevent oxidation into the above byꢀproduct).
1
H NMR spectra were recorded on Bruker Avance 300
spectrometers in CDCl3, CD3OD, and D2O; chemical shifts are
referenced to the residual signals of the deuterated solvent. Optiꢀ
cal rotation was measured on a Perkin—Elmer 341 polarimeter
(temperatureꢀcontrolled cell, l = 5 cm, 25 C).
Silica gel 60 (Merck) was used as a sorbent.
Analysis of amino acids was carried out by GLC on ꢀcycloꢀ
dextrin as a chiral phase with nꢀpropyl trifluoroacetates.
The enantiomeric purity of BINOL was verified by liquid
chromatography on a Chiralcel® IBꢀ3 column (hexane—PriOH
(90 : 10) as an eluent, flow rate 1.0 mL min–1, UV detector,
254 nm).
All alkylation reactions were carried out under dry argon.
Solvents were purified according to standard procedures.22
Elemental analysis of the compounds obtained was performed
at the Elemental Analysis Laboratory of the A. N. Nesmeyanov
Institute of Organoelement Compounds (Russian Academy
of Sciences).
(R)ꢀ3,3´ꢀBis[hydroxy(diphenyl)methyl]ꢀ1,1´ꢀbinaphthylꢀ2,2´ꢀ
diol ((R)ꢀBIMBOL) was prepared from (R)ꢀBINOL with
ee 99.9% (retention time 5.499 min) as described earlier;23
Decomposition of the complexes and isolation of amino acids
(with complex 3 as an example). A 18% aqueous solution of HCl
(0.4 mL) was added at 50 C to a stirred solution of alkylated

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Russ.Chem.Bull., Int.Ed., Vol. 61, No. 12, December, 2012
Belokon et al.
complex 3 (0.069 g, 1.5•10–4 mol) in methanol (0.2 mL). Stirꢀ
ring was continued until the red color of the solution characterꢀ
istic of these complexes disappeared. Then the mixture was
cooled to ~20 C. The precipitate of the achiral ligand
Nꢀ(2ꢀbenzoylphenyl)picolinamide that formed as hydrochloride
was filtered off. The mother liquor was concentrated in vacuo.
This was followed by addition of water and 5% aqueous NH3 to
reach pH 7—8. The residual amounts of the ligand were extractꢀ
ed with CHCl3.
The amino acid was isolated from an aqueous solution using
the DOWEX (50×8) cationꢀexchange resin (H+) with 5% aqueꢀ
ous NH3 as an eluent. Ammonia was removed from the eluate,
which was then concentrated in vacuo. The amino acid was anaꢀ
lyzed by GLC.
tained from complex 1 and 4ꢀiodobenzyl bromide as described
above. Yield 65% (0.029 g, 4.7•10–5 mol), []D25 +1349 (c 0.116,
CHCl3—MeOH), ee 40% (S), m.p. 140—142 C. 1H NMR
(CDCl3), : 2.86 and 3.11 (ABX system, 2 H, CH2, JAB = 13.7 Hz,
JAX = 2.6 Hz, JBX = 5.5 Hz); 4.43 (ABX system, 1 H, JAX = 2.6 Hz,
JBX = 5.5 Hz); 6.87 (d, 2 H, Ar, J = 4.1 Hz); 7.21—7.26 (m, 3 H,
Ar); 7.36—7.45 (m, 3 H, Ar); 7.56 (d, 2 H, Ar, J = 8.1 Hz);
7.61—7.66 (m, 3 H, Ar); 7.73 (d, 1 H, Ar, J = 5.3 Hz); 7.93
(d, 1 H, Ar, J = 7.8 Hz), 8.09 (t, 1 H, Ar, J = 7.7 Hz); 8.79
(d, 1 H, Ar, J = 8.6 Hz).
(Nꢀ{Phenyl[2ꢀ(pyridineꢀ2ꢀcarboxamido)phenyl]methylidene}ꢀ
(S)ꢀ4ꢀnitrophenylalaninatoꢀN,N´,N´´,O)nickel(II) (7) was obꢀ
tained from complex 1 and 4ꢀnitrobenzyl bromide as described
above. Yield 82% (0.032 g, 5.9•10–5 mol), []D25 +974 (c 0.107,
CHCl3—MeOH), ee 29% (S), m.p. 175—177 C. 1H NMR
(CDCl3), : 3.05 and 3.25 (ABX system, 2 H, CH2, JAB = 13.1 Hz,
JAX = 2.7 Hz, JBX = 5.7 Hz); 4.48 (ABX system, 1 H, JAX = 2.7 Hz,
JBX = 5.7 Hz); 6.88 (d, 2 H, Ar, J = 4.1 Hz); 7.22—7.27 (m, 1 H,
Ar); 7.33—7.46 (m, 3 H, Ar); 7.61 (d, 2 H, Ar, J = 8.4 Hz);
7.64—7.71 (m, 4 H, Ar); 7.81 (d, 1 H, Ar, J = 7.5 Hz); 7.96
(t, 1 H, Ar, J = 7.6 Hz); 8.07 (d, 2 H, Ar, J = 8.5 Hz); 8.76
(d, 1 H, Ar, J = 8.6 Hz).
Complexes 3—9 were obtained according to the optimized
procedure.
(Nꢀ{Phenyl[2ꢀ(pyridineꢀ2ꢀcarboxamido)phenyl]methylidene}ꢀ
(S)ꢀ2ꢀaminopentꢀ4ꢀenoatoꢀN,N´,N´´,O)nickel(II) (3). Yield 60%
(0.020 g, 4.3•10–5 mol), []D25 +2682 (c 0.1, CHCl3—MeOH),
ee 81% (S), m.p. 232—235 C. 1H NMR (CDCl3), : 2.53—2.58
(m, 2 H, CH2); 4.15—4.18 (m, 1 H, CH); 5.21 (d, 1 H,
CH=CHH, J = 17.0 Hz); 5.38 (d, 1 H, CH=CHH, J = 10.0 Hz);
6.42—6.55 (m, 1 H, CH=CH2); 6.83—6.87 (m, 2 H, Ar); 7.14—7.16
(m, 1 H, Ar); 7.34—7.43 (m, 2 H, Ar); 7.47—7.52 (m, 1 H, Ar);
7.57—7.62 (m, 3 H, Ar); 7.95 (d, 1 H, Ar, J = 7.1 Hz); 8.04—8.09
(m, 1 H, Ar); 8.27 (d, 1 H, Ar, J = 5.4 Hz); 8.98 (d, 1 H, Ar,
J = 8.6 Hz). Found (%): C, 63.24; H, 4.34; N, 9.16. C24H19N3O3Ni.
Calculated (%) C, 63.20; H, 4.20; N, 9.21.
(Nꢀ{Phenyl[2ꢀ(pyridineꢀ2ꢀcarboxamido)phenyl]methylidene}ꢀ
(S)ꢀ2ꢀaminobutanoatoꢀN,N´,N´´,O)nickel(II) (8) was obtained
from complex 1 and ethyl iodide as described above. The reꢀ
action time was 4 h. Yield 20% (0.0064 g, 1.4•10–5 mol),
25
[]D +358 (c 0.128, CHCl3—MeOH), ee 11% (S), m.p.
1
274—276 C. H NMR (CDCl3), : 1.45 (t, 3 H, J = 7.5 Hz);
(Nꢀ{Phenyl[2ꢀ(pyridineꢀ2ꢀcarboxamido)phenyl]methylidꢀ
ene}ꢀ(S)ꢀphenylalaninatoꢀN,N´,N´´,O)nickel(II) (4) was obꢀ
tained from complex 1 and benzyl bromide as described above.
1.80 (m, 1 H, CH2); 2.02 (m, 1 H, CH2); 4.06 (m, 1 H, CH);
6.81—6.87 (m, 2 H, Ar); 7.13 (d, 1 H, Ar, J = 6.9 Hz); 7.39—7.44
(m, 2 H, Ar); 7.51 (t, 1 H, Ar, J = 6.9 Hz), 7.55—7.61 (m, 3 H,
Ar); 7.96 (d, 1 H, Ar, J = 7.8 Hz), 8.07 (t, 1 H, Ar, J = 7.8 Hz);
8.30 (d, 1 H, Ar, J = 5.3 Hz), 9.00 (d, 1 H, Ar, J = 8.7 Hz).
2ꢀAminopentꢀ4ꢀenoic acid (9) was obtained by acid hydrolyꢀ
sis of complex 3 (0.069 g, 1.5•10–4 mol) (see above). Yield 62%
(0.0107 g, 9.3•10–5 mol), ee 81% (S), m.p. 250—252 C.
1H NMR (CDCl3), : 2.26—2.40 (m, 2 H, CH2); 3.50 (t, 1 H,
CH, J = 5.8 Hz); 4.97 (m, 2 H, CH=CH2); 5.46 (m, 1 H,
CH=CH2). Found (%): C, 52.14; H, 7.9; N, 12.18. C5H9NO2.
Calculated (%): C, 52.16; H, 7.88; N, 12.17.
25
Yield 67% (0.024 g, 4.8•10–5 mol), []D +1703 (c 0.12,
CHCl3—MeOH), ee 50% (S), m.p. 276—278 C. 1H NMR
(CDCl3), : 2.93 and 3.20 (ABX system, 2 H, CH2, JAB = 13.4 Hz,
JAX = 2.9 Hz, JBX = 5.5 Hz); 4.43 (ABX system, 1 H, JAX = 2.9 Hz,
JBX = 5.5 Hz); 6.86—6.90 (m, 2 H, Ar); 6.92 (t, 1 H, Ar, J = 7.4 Hz);
7.20—7.25 (m, 3 H, Ar); 7.34—7.44 (m, 3 H, Ar); 7.47 (d, 2 H,
Ar, J = 7.3 Hz); 7.58—7.65 (m, 3 H, Ar); 7.75 (d, 1 H, Ar,
J = 5.3 Hz); 7.83 (d, 1 H, Ar, J = 7.1 Hz); 7.97 (t, 1 H, Ar,
J = 7.7 Hz); 8.78 (d, 1 H, Ar, J = 8.6 Hz). Found (%): C, 66.46;
H, 4.10; N, 8.22. C28H21N3O3Ni. Calculated (%): C, 66.40;
H, 4.15; N, 8.30.
(Nꢀ{Phenyl[2ꢀ(pyridineꢀ2ꢀcarboxamido)phenyl]methylidene}ꢀ
(R)ꢀphenylalaninatoꢀN,N´,N´´,O)nickel(II) (Rꢀ4) was obtained
as described above from complex 1 and benzyl bromide
(1.1 equiv. with respect to 1) in the presence of (S)ꢀBIMBOL
and KOH (1 equiv.). Yield 40% (0.014 g, 2.9•10–5 mol),
[]D25 –1273 (c 0.093, CHCl3—MeOH), ee 37% (R).
(Nꢀ{Phenyl[2ꢀ(pyridineꢀ2ꢀcarboxamido)phenyl]methylidene}ꢀ
(S)ꢀ4ꢀfluorophenylalaninatoꢀN,N´,N´´,O)nickel(II) (5) was obꢀ
tained from complex 1 and 4ꢀfluorobenzyl bromide as described
above. Yield 60% (0.023 g, 4.3•10–5 mol), []D25 +2128 (c 0.115,
CHCl3—MeOH), ee 63% (S), m.p. 101—103 C. 1H NMR
(CDCl3), : 2.91 and 3.16 (ABX system, 2 H, CH2, JAB = 13.6 Hz,
JAX = 2.6 Hz, JBX = 5.3 Hz); 4.41 (ABX system, 1 H,
JAX = 2.6 Hz, JBX = 5.3 Hz); 6.86—6.94 (m, 4 H, Ar); 7.18—7.25
(m, 1 H, Ar); 7.37—7.45 (m, 5 H, Ar); 7.62—7.66 (m, 3 H, Ar);
7.76 (d, 1 H, Ar, J = 5.3 Hz); 7.88 (d, 1 H, Ar, J = 7.6 Hz), 8.02
(t, 1 H, Ar, J = 7.7 Hz); 8.77 (d, 1 H, Ar, J = 8.6 Hz).
This work was financially supported by the Russian
Foundation for Basic Research (Project No. 11ꢀ03ꢀ00206).
References
1. P. J. Knerr, W. van der Donk, J. Am. Chem. Soc., 2012,
134, 7648.
2. P. Conti, L. Tamborini, A. Pinto, A. Blondel, P. Minoprio,
A. Mozarelli, C. De Micheli, Chem. Rev., 2011, 111, 6919.
3. J. T. Ngo, D. A. Tirrell, Acc. Chem. Res., 2011, 44, 677.
4. I. N. Ugwumba, K. Ozawa, Z. Xu, F. Ely, J. Foo, A. J. Herit,
C. Coppin, S. Brown, M. C. Taylor, D. L. Ollis, L. N.
Mander, G. Schenk, N. E. Dixon, G. Otting, J. G. Oakeꢀ
shot, C. J. Jackson, J. Am. Chem. Soc., 2011, 133, 326.
5. J. Paradowska, M. Stodulski, J. Mlynarski, Angew. Chem.
Int. Ed., 2009, 48, 2.
6. M. Breuer, K. Ditrich, T. Habicher, B. Hauer, M. Kebeler,
R. Sturmer, T. Zelinski, Angew. Chem. Int. Ed., 2004, 43, 788.
7. S. Matsunaga, T. Yoshino, Chem. Rev., 2011, 11, 260.
(Nꢀ{Phenyl[2ꢀ(pyridineꢀ2ꢀcarboxamido)phenyl]methylidene}ꢀ
(S)ꢀ4ꢀiodophenylalaninatoꢀN,N´,N´´,O)nickel(II) (6) was obꢀ

BIMBOLꢀcatalyzed alkylation of nickel(II) complexes Russ.Chem.Bull., Int.Ed., Vol. 61, No. 12, December, 2012
2349
8. A. Viso, R. F. de la Pradilla, M. Tortosa, A. Garcia, A. Flores,
Chem. Rev., 2011, 111, PR1—42.
hyan, A. T. Tsaloev, K. K. Babievsky, Amino Acids, 2012,
43, 299.
9. C. Cativiela, M. D. DiazꢀdeꢀVillegas, Tetrahedron: Asymꢀ
metry, 2007, 18, 569.
10. K. Maruoka, Chem. Rev., 2010, 10, 254.
11. X.ꢀL. Qiu, F.ꢀL. Qing, Eur. J. Org. Chem., 2011, 3261.
12. M. J. O´Donnell, Acc. Chem. Res., 2004, 37, 506.
13. M. J. O´Donnell, Aldrich Acta, 2001, 34, 3.
21. Y. N. Belokon, N. B. Bespalova, T. D. Churkina, I. Cisaroꢀ
va, M. G. Ezernitskaya, S. R. Harutyunyan, R. Hrdina,
H. B. Kagan, P. Kocovsky, K. A. Kochetkov, O. V. Larionov,
K. A. Lyssenko, M. North, M. Polasek, A. S. Peregudov,
V. V. Prisyazhnyuk, S. Vyscocil, J. Am. Chem. Soc., 2003,
125, 12860.
14. T. Hashimoto, K. Maruoka, Chem. Rev., 2007, 107, 5656.
15. T. Ooi, K. Maruoka, Angew. Chem. Int. Ed., 2007, 46, 4222.
16. T. Ooi, K. Maruoka, Aldrich Acta, 2007, 40, 77.
17. K. Maruoka, T. Ooi, T. Kano, Chem. Commun., 2007, 1487.
18. K. Maruoka, Org. Proc. Res. Dev., 2008, 12, 679.
19. Y. N. Belokon, K. A. Kochetkov, T. D. Churkina, N. S.
Ikonnikov, A. A. Chesnokov, O. V. Larionov, I. Singh, V. S.
Parmar, S. Vyscocil, H. B. Kagan, J. Org. Chem., 2000,
65, 7041.
22. A. J. Gordon, R. A. Ford, The Chemist´s Companion: A Handꢀ
book of Practical Data, Techniques, and References, John
Wiley and Sons, New York, 1972.
23. Q. Wang, X. Chen, L. Tao, L. Wang, D. Xiao, X.ꢀQ. Yu,
L. Pu, J. Org. Chem., 2007, 72, 97.
24. Y.ꢀL. Zhang, Q.ꢀH. Fan, J. Chem. Res. (S), 2005, 778.
25. V. A. Soloshonok, H. Ueki, J. Am. Chem. Soc., 2007,
129, 2426.
20. Y. N. Belokon, Z. T. Gugkaeva, K. V. Hakobyan, V. I.
Maleev, M. A. Moskalenko, V. N. Khrustalev, A. S. Sagꢀ
Received September 21, 2012;
in revised form November 12, 2012