Diastereomeric P*-mono- and P*,P*-bidentate diamidophosphite ligands based on 1,4:3,6-dianhydro-d-mannitol in asymmetric metallocomplex catalysis

Article abstract of DOI:10.1007/s11172-008-0327-x

Synthesis of diastereomeric mono-and bidentate diamidophosphites bearing P*-stereo-centers and phosphabicyclo[3.3.0]octane backbone and their coordination with rhodium(i) and palladium(ii) are considered. Their use in Rh-catalyzed asymmetric allylation allowed one to achieve 87% ee values and the use in Rh-catalyzed asymmetric hydrogenation gave up to 98% ee.

Full text of DOI:10.1007/s11172-008-0327-x

Russian Chemical Bulletin, International Edition, Vol. 57, No. 11, pp. 2311—2319, November, 2008
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Diastereomeric P*ꢀmonoꢀ and P*,P*ꢀbidentate diamidophosphite
ligands based on 1,4:3,6ꢀdianhydroꢀDꢀmannitol in asymmetric
metallocomplex catalysis
K. N. Gavrilov,a S. V. Zheglov,a P. A. Vologzhanin,a E. A. Rastorguev,a A. A. Shiryaev,a
M. G. Maksimova,a S. E. Lyubimov,b E. B. Benetsky,b A. S. Safronov,b P. V. Petrovskii,b
V. A. Davankov,b B. Schäffner,c and A. Börnerc
aDepartment of Chemistry, S. A. Esenin Ryazan State University,
46 ul. Svobody, 390000 Ryazan, Russian Federation.
Fax: +7 (4912) 775 498. Eꢀmail: k.gavrilov@rsu.edu.ru
bA. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences,
28 ul. Vavilova, 119991 Moscow, Russian Federation.
Fax: +7 (495) 135 6471. Eꢀmail: lssp452@mail.ru
cLeibnizꢀInstitut für Katalyse, Universität Rostock e.V.,
29a A.ꢀEinsteinꢀStr., 18059 Rostock, Germany.
Fax: 49 381 12815000. Eꢀmail: Armin.Boerner@catalysis.de
Synthesis of diastereomeric monoꢀ and bidentate diamidophosphites bearing P*ꢀstereoꢀ
centers and phosphabicyclo[3.3.0]octane backbone and their coordination with rhodium(I)
and palladium(II) are considered. Their use in Rhꢀcatalyzed asymmetric allylation allowed one
to achieve 87% ee values and the use in Rhꢀcatalyzed asymmetric hydrogenation gave up to
98% ee.
Key words: P*ꢀchiral diamidophosphites, ligands, rhodium complexes, palladium comꢀ
plexes, asymmetric allylation, asymmetric hydrogenation, deracemization, 1,4:3,6ꢀdianhydroꢀ
Dꢀmannitol.
Asymmetric metallocomplex catalysis represents a
highly efficient methodology for the preparation of valuꢀ
able enantiomerically pure organic and organoelement
compounds.1—3 Chemical and optical yields close to quanꢀ
titative are achieved in enantioselective catalytic transforꢀ
mations due to the most careful optimization of various
reaction parameters. The key unit of the optimization
process is the correct choice of the ligand group and ratioꢀ
nal design of each ligand from this ligand group.4 Among
phosphorusꢀcontaining ligands, the predominant position
is occupied by P,Pꢀbidentate ligands. However, in the
recent time many researchers use more electronꢀwithꢀ
drawing compounds of the phosphite type. The latter are
especially attractive by simplicity of their preparation from
accessible precursors and stability to oxidative destrucꢀ
tion. In addition, they are characterized by the pronounced
πꢀacidity and low cost.5—10 At the same time, only several
promising P*,P*ꢀbidentate ligands of the phosphite type
bearing stereogenic phosphorus atoms are described.11—13
This is rather surprising, because it is well known2
that ligands with asymmetric donor atoms are excellent
stereoselectors.
It is worth noting that cheap chiral diols bearing
several C*ꢀstereocenters are a very abundant pool for the
synthesis of P,Pꢀbidentate phosphites.4—10 In particular, a
series of phosphite and phosphinite ligands 1—3 based on
1,4:3,6ꢀdianhydroꢀDꢀmannitol (see below) were successꢀ
fully used in selected reactions of asymmetric hydrogenaꢀ
tion and allylic substitution.14—17
t
R = R´ = H (a); R = Me, R´ = H (b); R = R´ = Bu (c)
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2266—2274, November, 2008.
1066ꢀ5285/08/5711ꢀ2311 © 2008 Springer Science+Business Media, Inc.

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Russ.Chem.Bull., Int.Ed., Vol. 57, No. 11, November, 2008
Gavrilov et al.
and application in asymmetric catalysis of the first P*,P*ꢀ
bidentate diamidophosphite (SC,RP)ꢀ4 bearing the
phosphabicyclo[3.3.0]octane fragment. In the present
work, we present the data on its further catalytic use and
comparison with the efficiency of its specially obtained
diastereomer (RC,SP)ꢀ4 with the opposite absolute conꢀ
figuration of the 2´ꢀP*ꢀ and 5´ꢀC*ꢀstereocenters. In addiꢀ
tion, P*,P*ꢀbidentate ligands 4 and analogous P*ꢀ
monodentate ligands 5 also based on 1,4:3,6ꢀdianhydroꢀ
Dꢀmannitol were compared.
Results and Discussion
The synthesis of new diamidophosphites with P*ꢀ
stereocenters was carried out according to Scheme 1. It
should be mentioned that this method is convenient and
simple, being performed through the oneꢀstep phosphoꢀ
rylation of 1,4:3,6ꢀdianhydroꢀDꢀmannitol 7 or its Oꢀbenꢀ
zyl derivative 8 by (2R,5S)ꢀ and (2S,5R)ꢀenantiomers of
reactant 6 in THF. In turn, (2R,5S)ꢀ6 and (2S,5R)ꢀ6 are
obtained18 easily and in high yield from accessible (S)ꢀ
and (R)ꢀglutamic anilides.25,26
At the same time, we proposed18—23 a series of P*ꢀ
monoꢀ and P*,Nꢀbidentate diamidophosphites representꢀ
ing a new highly efficient ligand group for enantioselective
processes of Pdꢀcatalyzed allylation and Rhꢀcatalyzed
hydrogenation. We have recently reported24 the synthesis
As follows from the 31P NMR data (Table 1), comꢀ
pounds 4 and 5 are stereoindividual. The ligands (L) based
on (S)ꢀglutamic acid (SC,RP)ꢀ4 and (SC,RP)ꢀ5 have the
Scheme 1

Dianhydromannitol diamidophosphite ligands
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 11, November, 2008 2313
Table 1. Data of 31P NMR spectroscopy (CDCl3) for ligands 4
and 5 and their cationic rhodium and palladium complexes 9—12
Scheme 3
Соединение
δ
1JP,Rh/Hz
Р
(SC,RP)ꢀ4
(RC,SP)ꢀ4
(SC,RP)ꢀ5
(RC,SP)ꢀ5
(SC,RP)ꢀ9
(RC,SP)ꢀ9
(SC,RP)ꢀ10
(RC,SP)ꢀ10
(SC,RP)ꢀ11
(RC,SP)ꢀ11
(SC,RP)ꢀ12
(RC,SP)ꢀ12
123.1
122.9
123.1
123.0
111.5
113.6
117.7
113.4
114.3
110.9
119.0
113.7
222.2
224.5
223.0
223.7
(S)ꢀconfiguration of the 5´ꢀC*ꢀstereocenters and (R)ꢀconꢀ
figuration of the 2´ꢀP*ꢀstereocenters, and their “unnatuꢀ
ral” diastereomers (RC,SP)ꢀ4 and (RC,SP)ꢀ5 have the
opposite configurations: (R)ꢀconfiguration for 5´ꢀC* and
(S)ꢀconfiguration for 2´ꢀP*.
P*ꢀMonodentate diamidophosphites (SC,RP)ꢀ5 and
(RC,SP)ꢀ5 form cationic complexes 11 and 12 also bearing
two phosphorus centers cisꢀarranged at Rh and Pd
I
II
The 13C NMR spectra of these substances exhibit
(Scheme 3).
2
The sameꢀtype structure of the first coordination
sphere of rhodium complexes 9 and 11 and palladium
complexes 10 and 12 is indicated by the substantial proxꢀ
imity of their chemical shifts and spinꢀspin coupling
constants in the 31P NMR spectra (see Table 1). In the
31P NMR spectra, the signals of compounds 10 and 12
are narrow symmetric singlets, indicating either the fast
mutual transformation of their exoꢀ and endoꢀisomers, or
the absence of one of them (see Ref. 31).
Diamidophosphites 4 and 5 were tested in the
Rhꢀcatalyzed asymmetric hydrogenation of a series
of prochiral unsaturated methyl esters 13, 15, and 17
(Scheme 4, Table 2).
high values of spinꢀspin coupling constants JC(8´),P
(35.8—38.3 Hz), indicating cisꢀorientation between the
lone electron pair of the phosphorus atom and C(8´) atom
and pseudoequatorial orientation of the exocyclic subꢀ
stituents at the phosphorus atom.18,26—30
Ligands 4 and 5 are rather stable in air and capable of
prolong storage under a dry atmosphere. Similarly to reꢀ
lated compounds 1—3 (see Refs 4—17), (SC,RP)ꢀ4,
(RC,SP)ꢀ4 are typical chelating agents by their coorꢀ
dination compounds. Particularly, their reactions
with [Rh(COD)2]BF4 (COD is cyclooctaꢀ1,5ꢀdiene) and
[Pd(All)Cl]2 (in the presence of AgBF4) afford cationic
metallochelates 9 and 10 with cisꢀorientation of the phosꢀ
phorus atoms (Scheme 2).
Scheme 4
Scheme 2

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Gavrilov et al.
Table 2. Data on the Rhꢀcatalyzed hydrogenation of substrates 13, 15, and 17 (5 atm H2, CH2Cl2, P/Rh = 2, 20 °C, 24 h)
Entry
Catalyst
Substrate
Conversion (%)
ee (%)
1
2
3
4
5
6
7
8
[Rh(COD)2]BF4/(SC,RP)ꢀ4
[Rh(COD)2]SbF6/(SC,RP)ꢀ4
[Rh(COD)2]BF4/(RC,SP)ꢀ4
[Rh(COD)2]SbF6/(RC,SP)ꢀ4
[Rh(COD)2]BF4/(SC,RP)ꢀ5
[Rh(COD)2]BF4/(RC,SP)ꢀ5
[Rh(COD)2]BF4/(SC,RP)ꢀ4
[Rh(COD)2]BF4/(RC,SP)ꢀ4
[Rh(COD)2]BF4/(SC,RP)ꢀ4
[Rh(COD)2]SbF6/(SC,RP)ꢀ4
[Rh(COD)2]SbF6/(RC,SP)ꢀ4
[Rh(COD)2]BF4/(SC,RP)ꢀ5
[Rh(COD)2]BF4/(RC,SP)ꢀ5
13
13
13
13
13
13
15
15
17
17
17
17
17
100
100
65
100
75
90
100
85
100
100
100
100
100
86 (S)
81 (S)
39 (R)
41 (R)
15 (S)
57 (R)
87 (R)
51 (R)
24 (R)
65 (R)
11 (S)
3 (R)
9
10
11
12
13
2 (S)
In all cases, “natural” diastereomer (SC,RP)ꢀ4 proꢀ
vides much higher ee values of products 14, 16, and 18
(and sometimes the conversion of the starting substrates)
than (RC,SP)ꢀ4. The use of the both isomers of ligand 4
makes it possible to obtain products 14 and 18 with the
opposite absolute configurations (see Table 2, entries
1—4 and 9—11). It is interesting that in the hydrogenaꢀ
tion of 17 the [Rh(COD)2]SbF6 precatalyst provides conꢀ
siderably higher enantioselectivity than [Rh(COD)2]BF4
(see Table 2, entries 9 and 10). On the contrary, “unnatuꢀ
ral” P*ꢀmonodentate diamidophosphite (RC,SP)ꢀ5 maniꢀ
fests the enhanced activity and asymmetric induction in
the synthesis of 14 compared to its “natural” diastereoꢀ
mer (SC,RP)ꢀ5 (see Table 2, entries 5 and 6). At the same
time, in the hydrogenation of substrate 17 the use of the
both diastereomers of ligand 5 provides almost racemic
product 18 (see Table 2, entries 12 and 13). It should be
mentioned that, unlike ligands of the phosphite type based
on 2,2´ꢀdihydroxyꢀ1,1´ꢀbinaphthyl,32,33 monodentate
diamidophosphites 5 in Rhꢀcatalyzed hydrogenation are
worse stereoselectors than bidentate chelating agents 4.
Compounds 4 and 5 were also used in Pdꢀcatalyzed
allylic substitution with (E)ꢀ1,3ꢀdiphenylallyl acetate 19
as a substrate (Scheme 5, Tables 3 and 4).
Scheme 5
In the allylic sulfonylation of 19 with sodium
pꢀtoluenesulfinate, isomeric ligands 4 provide the formaꢀ
tion of the opposite enantiomers of sulfone 20, and the
efficiency of (SC,RP)ꢀ4 is somewhat higher as a whole.
However, monodentate diamidophosphite (SC,RP)ꢀ5 is
most efficient, and (S)ꢀ20 is formed with 96% yield and
ee 97% in the reaction involving (SC,RP)ꢀ5 (Table 3, entry
8). In the case of alkylation of 19 by dimethyl malonate,
the both diastereomers (SC,RP)ꢀ4 and (RC,SP)ꢀ4 turned
out to be excellent stereoselectors that perform the
Pdꢀcatalyzed synthesis of (S)ꢀ21 with the enantioselecꢀ
tivity up to 98%, and (SC,RP)ꢀ4 is again somewhat more
efficient (Table 3, entries 11—13 and 14—16).
*BSA is N,Oꢀbis(trimethylsilyl)acetamide
(E)ꢀ1,3ꢀdiphenylallyl acetate 19. Particularly, in the
reaction involving benzylamine and ligands 4 the achieved
ee value was up to 92%; the high asymmetric induction
was observed for (SC,RP)ꢀ4 and CH2Cl2 as solvent
(Table 4, entries 1—4). The allylic amination of 19 by
pyrrolidine using the [Pd(All)Cl]2/(SC,RP)ꢀ4 catalytic
system or isolated complex (SC,RP)ꢀ10 occurs with the
quantitative conversion and high enantioselectivity for
product (R)ꢀ23 (87–95%, Table 4, entries 5—10) regardꢀ
less of the L/Pd molar ratio and nature of the solvent.
Various nitrogenꢀcontaining nucleophiles (Scheme 5)
were involved in the Pdꢀcatalyzed allylic amination of

Dianhydromannitol diamidophosphite ligands
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 11, November, 2008 2315
Table 3. Data on the Pdꢀcatalyzed allylic sulfonylation of 19 with sodium pꢀtoluenesulfinite and the allylic alkylation of 19 with
dimethyl malonate (20 °C, 48 h)
Entry
Catalyst
Solvent
Conversion (%)*
еe (%)
Allylic sulfonylation
1
2
3
4
5
6
7
8
9
10
[Pd(All)Cl]2/2(SC,RP)ꢀ4
[Pd(All)Cl]2/4(SC,RP)ꢀ4
(SC,RP)ꢀ10
[Pd(All)Cl]2/2(RC,SP)ꢀ4
[Pd(All)Cl]2/4(RC,SP)ꢀ4
(RC,SP)ꢀ10
[Pd(All)Cl]2/2(SC,RP)ꢀ5
[Pd(All)Cl]2/4(SC,RP)ꢀ5
(SC,RP)ꢀ12
THF
THF
THF
THF
THF
THF
THF
THF
THF
THF
75
69
94
65
88
43
87
96
91
35
68 (S)
50 (S)
89 (S)
78 (R)
68 (R)
50 (R)
92 (S)
97 (S)
90 (S)
50 (S)
(RC,SP)ꢀ12
Allylic alkylation
11
12
13
14
15
16
[Pd(All)Cl]2/2(SC,RP)ꢀ4
[Pd(All)Cl]2/4(SC,RP)ꢀ4
(SC,RP)ꢀ10
[Pd(All)Cl]2/2(RC,SP)ꢀ4
[Pd(All)Cl]2/4(RC,SP)ꢀ4
(RC,SP)ꢀ10
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
72
80
58
62
64
40
98 (S)
95 (S)
98 (S)
88 (S)
90 (S)
96 (S)
*Chemical yield of the product of allylic sulfonylation of 20.
Table 4. Data on the Pdꢀcatalyzed allylic amination of 19 with benzylamine (20 °C, 12 h) and pyrrolidine (20 °C, 48 h)
Entry
Catalyst
Solvent
Conversion (%)*
еe (%)
Allylic amination with benzylamine
1
2
3
4
[Pd(All)Cl]2/2(SC,RP)ꢀ4
[Pd(All)Cl]2/2(SC,RP)ꢀ4
[Pd(All)Cl]2/2(RC,SP)ꢀ4
[Pd(All)Cl]2/2(RC,SP)ꢀ4
CH2Cl2
PC*
CH2Cl2
PC
40
98
99
64
92 (R)
72 (R)
78 (R)
37 (R)
Allylic amination with pyrrolidine
5
6
7
8
[Pd(All)Cl]2/2(SC,RP)ꢀ4
[Pd(All)Cl]2/4(SC,RP)ꢀ4
[Pd(All)Cl]2/2(SC,RP)ꢀ4
[Pd(All)Cl]2/4(SC,RP)ꢀ4
(SC,RP)ꢀ10
CH2Cl2
CH2Cl2
THF
THF
CH2Cl2
THF
CH2Cl2
CH2Cl2
THF
THF
CH2Cl2
THF
CH2Cl2
CH2Cl2
THF
THF
CH2Cl2
THF
CH2Cl2
CH2Cl2
THF
THF
CH2Cl2
THF
100
100
100
100
100
99
100
100
60
84
100
77
100
100
40
88
100
96
100
100
23
85
100
89
92 (R)
93 (R)
94 (R)
95 (R)
90 (R)
87 (R)
73 (S)
79 (S)
75 (S)
76 (S)
69 (S)
66 (S)
83 (R)
90 (R)
25 (R)
87 (R)
70 (R)
92 (R)
78 (S)
80 (S)
68 (S)
76 (S)
72 (S)
70 (S)
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
(SC,RP)ꢀ10
[Pd(All)Cl]2/2(RC,SP)ꢀ4
[Pd(All)Cl]2/4(RC,SP)ꢀ4
[Pd(All)Cl]2/2(RC,SP)ꢀ4
[Pd(All)Cl]2/4(RC,SP)ꢀ4
(RC,SP)ꢀ10
(RC,SP)ꢀ10
[Pd(All)Cl]2/2(SC,RP)ꢀ5
[Pd(All)Cl]2/4(SC,RP)ꢀ5
[Pd(All)Cl]2/2(SC,RP)ꢀ5
[Pd(All)Cl]2/4(SC,RP)ꢀ5
(SC,RP)ꢀ12
(SC,RP)ꢀ12
[Pd(All)Cl]2/2(RC,SP)ꢀ5
[Pd(All)Cl]2/4(RC,SP)ꢀ5
[Pd(All)Cl]2/2(RC,SP)ꢀ5
[Pd(All)Cl]2/4(RC,SP)ꢀ5
(RC,SP)ꢀ12
(RC,SP)ꢀ12
* PC is propylene carbonate.

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Gavrilov et al.
Table 5. Data on the Pdꢀcatalyzed allylic amination of 19 with dipropylamine (20 °C, 48 h)
Catalyst
Solvent
Conversion (%)*
еe (%)
[Pd(All)Cl]2/2(SC,RP)ꢀ4
[Pd(All)Cl]2/4(SC,RP)ꢀ4
[Pd(All)Cl]2/2(SC,RP)ꢀ4
[Pd(All)Cl]2/4(SC,RP)ꢀ4
(SC,RP)ꢀ10
CH2Cl2
CH2Cl2
THF
THF
CH2Cl2
THF
CH2Cl2
CH2Cl2
THF
THF
CH2Cl2
THF
CH2Cl2
CH2Cl2
THF
THF
CH2Cl2
THF
CH2Cl2
CH2Cl2
THF
THF
CH2Cl2
THF
100
100
47
100
91
44
98
100
37
72
100
47
96
90
34
52
100
71
87
100
29
90 (+)
77 (+)
76 (+)
70 (+)
88 (+)
90 (+)
68 (–)
75 (–)
72 (–)
71 (–)
79 (–)
76 (–)
76 (+)
82 (+)
75 (+)
77 (+)
48 (+)
68 (+)
68 (–)
74 (–)
70 (–)
70 (–)
28 (–)
54 (–)
(SC,RP)ꢀ10
[Pd(All)Cl]2/2(RC,SP)ꢀ4
[Pd(All)Cl]2/4(RC,SP)ꢀ4
[Pd(All)Cl]2/2(RC,SP)ꢀ4
[Pd(All)Cl]2/4(RC,SP)ꢀ4
(RC,SP)ꢀ10
(RC,SP)ꢀ10
[Pd(All)Cl]2/2(SC,RP)ꢀ5
[Pd(All)Cl]2/4(SC,RP)ꢀ5
[Pd(All)Cl]2/2(SC,RP)ꢀ5
[Pd(All)Cl]2/4(SC,RP)ꢀ5
(SC,RP)ꢀ12
(SC,RP)ꢀ12
[Pd(All)Cl]2/2(RC,SP)ꢀ5
[Pd(All)Cl]2/4(RC,SP)ꢀ5
[Pd(All)Cl]2/2(RC,SP)ꢀ5
[Pd(All)Cl]2/4(RC,SP)ꢀ5
(RC,SP)ꢀ12
42
100
74
(RC,SP)ꢀ12
Scheme 6
Under the same conditions, (RC,SP)ꢀ4 provides lower conꢀ
version (in THF) and enantioselectivity (ee 66–79% for
(S)ꢀ23, Table 4, entries 11—16). Similarly P*ꢀmonodenꢀ
tate diamidophosphite (SC,RP)ꢀ5 is a better stereoselector
than its “unnatural” diastereomer (RC,SP)ꢀ5: (R)ꢀ23 and
(S)ꢀ23 are formed with enantioselectivities up to 92
and 80%, respectively (Table 4, entries 17—28). In this
case, P*ꢀmonodentate ligands 5 are not almost inferior to
P*,P*ꢀbidentate 4 in efficiency.
The deracemization of allylic esters is usually carried
out in a CH2Cl2—H2O (9 : 1) medium.34 However, we
used a unique procedure22 carried out in anhydrous
CH2Cl2. This method makes it possible to exclude the
stage of ester hydrolysis from the catalytic cycle and to widely
use the waterꢀsensitive phosphorusꢀcontaining ligands.
Under these conditions, the [Pd(All)Cl]2/(SC,RP)ꢀ4 (1 : 2)
catalytic system provides good conversion of 25 (84%)
and ee of product (R)ꢀ26 (82%). The analogous catalyst
based on “unnatural” diastereomer (RC,SP)ꢀ4 is much
less efficient: only the 50% conversion of 25 and 13% ee
for product (R)ꢀ26 were achieved here.
Summating the aforesaid, we can conclude the
following. In asymmetric Rhꢀcatalyzed hydrogenation
P*ꢀmonodentate diamidophosphites 5 are less efficient
stereoselectors than P*,P*ꢀbidentate ligands 4, whereas
in Pdꢀcatalyzed allylation they can demonstrate the close
and even high productivity. Almost in all cases, “natural”
diastereomers (SC,RP)ꢀ4 and (SC,RP)ꢀ5 provide better
enantioselectivity than “unnatural” (RC,SP)ꢀ4 and (RC,SP)ꢀ5.
Analogous dependences are characteristic of the
amination of 19 with dipropylamine (Scheme 5, Table 5).
The best asymmetric induction is also achieved when
“natural” diamidophosphite ligands are used: ee 70–90%
for (+)ꢀ24 in the case of (SC,RP)ꢀ4 and ee 68–79%
for (–)ꢀ24 — (RC,SP)ꢀ4; ее 48—82% for (+)ꢀ24 when
(SC,RP)ꢀ5 is used and ee 28—74% for (–)ꢀ24 using
(RC,SP)ꢀ5 (Table 4). Enantioselectivity is poorly sensitive
to the L/Pd molar ratio and solvent nature. On the
contrary, the conversion of substrate 19 decreases from
the quantitative one in CH2Cl2 to moderate in THF.
In this case, P*,P*ꢀbidentate compounds 4 turned out
to be somewhat more efficient than P*ꢀmonodentate
compounds 5.
Bidentate ligands (SC,RP)ꢀ4 and (RC,SP)ꢀ4 were use in
the practically significant deracemization reaction that
provides valuable optically active allylic alcohols,34 including
(E)ꢀ1,3ꢀdiphenylpropꢀ2ꢀenꢀ1ꢀol (26). Ethyl (E)ꢀ1,3ꢀdiꢀ
phenylallyl carbonate 25 was chosen as the substrate
(Scheme 6).

Dianhydromannitol diamidophosphite ligands
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 11, November, 2008 2317
sodium pꢀtoluenesulfinate and dimethyl malonate are commerꢀ
cially available (Aldrich).
In the most part of catalytic transformations, the use of
isomeric ligands makes it possible to obtain products with
opposite absolute configurations. It is important that
P*,P*ꢀbidentate diamidophosphites 4 are more universal
stereoinductors than the known phosphites and phosꢀ
phinites 1—3. For example, ligand (SC,RP)ꢀ4 is somewhat
inferior to 1 in enantioselectivity in the Rhꢀcatalyzed
synthesis of 11 (86 and 98% ee, respectively) but provides
nearly the same optical yield of product 16 (87 and 89%).14
At the same time, in the Pdꢀcatalyzed allylic substitution
of (E)ꢀ1,3ꢀdiphenylallyl acetate 19 involving benzylamine
and dimethyl malonate, compounds 1c, 2, and 3 make it
possible to achieve ee not higher than 49% (see Refs 15
and 17), whereas ligands 4 provide enantioselectivity close
to the absolute value.
Synthesis of P,Pꢀbidentate ligands (SC,RP)ꢀ4 and (RC,SP)ꢀ4
(general procedure). A solution of 1,4:3,6ꢀdianhydroꢀDꢀmannitol
(0.73 g, 5 mmol) in THF (15 mL) was added dropwise for 20 min
to a vigorously stirred solution of (2R,5S)ꢀ or (2S,5R)ꢀ2ꢀchloroꢀ
3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicyclo[3.3.0]octane (2.41 g,
10 mmol) and Et3N (1.45 mL, 10.4 mmol) in THF (25 mL) at
20 °C. The resulting mixture was heated to boiling, refluxed
with stirring for 1.5 h, and cooled to 20 °C, and Et3N·HCl was
removed by filtration. The filtrate was evaporated in vacuo
(40 Torr). The obtained residue was washed with hexane and
dried in vacuo (45 min, 1 Torr).
3,6ꢀBis[(2R,5S)ꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octꢀ2ꢀyloxy]ꢀ(3R,3aS,6R,6aS)ꢀhexahydrofuro[3,2ꢀb]ꢀ
furan ((SC,RP)ꢀ4). The yield was 2.02 g (73%), white powder,
m.p. 69—70 °C. Found (%): C, 60.89; H, 6.63; N, 9.89.
C28H36N4O4P2. Calculated (%): C, 60.64; H, 6.54; N, 10.10.
13C NMR (CDCl3), δ: 26.3 (d, C(7´), 3J = 3.7 Hz), 31.9 (s,
C(6´)), 48.3 (d, С(8´), 2J = 37.9 Hz), 54.7 (d, С(4´), 2J = 6.9 Hz),
62.5 (d, C(5´), 2J = 8.4 Hz), 71.3 (s, C(2), C(5)), 72.7 (d, C(3),
Experimental
31P and 13C NMR spectra were recorded on a Bruker Avanceꢀ
400 instrument (161.98 and 100.61 MHz) relative to 85% H3PO4
in D2O and CDCl3 (δ 76.91), respectively. Signals in the 13C NMR
spectra were assigned Cusing the Jꢀmodulated echo procedure. Mass
spectra with electron impact ionization (EI, 70 eV) were
measured in a Varian MATꢀ311 instrument, mass spectra with
electrospray ionization (ESI) were obtained on a Finnigan LCQ
Advantage instrument, and those with laser desorption ionization
(MALDI TOF/TOF) were detected on a Bruker Daltonics
Ultraflex instrument. Elemental analysis was carried out at the
Laboratory of Organic Microanalysis at the A. N. Nesmeyanov
Institute of Organoelement Compounds (Russian Academy of
Sciences).
All reactions were carried out under dry argon atmosphere
in absolute solvents. The (2R,5S)ꢀ and (2S,5R)ꢀenantiomers of
phosphorylating agent 6, namely, 2ꢀchloroꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ
2ꢀphosphabicyclo[3.3.0]octane and Oꢀbenzylꢀ1,4:3,6ꢀdianhydroꢀ
Dꢀmannitol 8, as well as the starting complexes [Rh(COD)2]BF4
and [Pd(All)Cl]2 were obtained by known procedures.18,35—37
The starting substrates, viz., methyl (Z)ꢀ2ꢀacetamidoꢀ
3ꢀphenylacrylate 17, (E)ꢀ1,3ꢀdiphenylallyl acetate 19, and
ethyl (E)ꢀ1,3ꢀdiphenylallyl carbonate 25, were synthesized
according to known procedures.38,37,39 Catalytic experiments
on the asymmetric hydrogenation of substrates 13, 15, and 17
and determination of their conversions and enantiomeric excesses
for products 14, 16, and 18 (using GL and HPLC, chiral columns
packed with GꢀTA, HydrodexꢀβꢀTBDAc, Lipodex E, and Daicel
Chiralcel ODꢀH) were carried out according to published
procedures.30,40,41 Catalytic experiments on the asymmetric
allylation of substrate 19 by sodium pꢀtoluenesulfinate, benzylꢀ
amine, pyrrolidine, and dipropylamine and determination of its
conversion and enantiomeric composition of products 20—24
(HPLC, chiral columns (R,R)ꢀWHELKꢀ01 and Daicel Chiralcel
ODꢀH) were carried out according to published procedures.18,42—44
Catalytic experiments on the deracemization of substrate 25 and
determination of its conversion and its product 26 (HPLC, chiral
column Daicel Chiralcel ODꢀH) were carried out using known
procedures.22
2
3
C(6), J = 5.5 Hz), 80.8 (d, C(3a), C(6a), J = 1.8 Hz), 115.0
(d, CHAr, 3J = 11.7 Hz), 119.2 (s, CHAr), 129.0 (s, CHAr), 145.5
(d, CAr, 2J = 16.4 Hz). MS (EI), m/z (Irel (%)): 554 [M]+ (8).
3,6ꢀBis[(2S,5R)ꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octꢀ2ꢀyloxy]ꢀ(3R,3aS,6R,6aS)ꢀhexahydrofuro[3,2ꢀb]ꢀ
furan ((RC,SP)ꢀ4). The yield was 2.16 g (78%), white powder,
m.p. 109—110 °C. Found (%): C, 60.94; H, 6.68; N, 9.95.
C28H36N4O4P2. Calculated (%): C, 60.64; H, 6.54; N, 10.10.
13С NMR (CDCl3), δ: 26.4 (d, С(7´), 3J = 4.0 Hz), 31.8 (s,
C(6´)), 48.1 (d, С(8´), 2J = 35.8 Hz), 54.8 (d, С(4´), 2J = 7.3 Hz),
62.9 (d, С(5´), 2J = 8.0 Hz), 72.7 (s, C(2), C(5)), 73.5 (d, C(3),
C(6), 2J = 5.4 Hz), 80.5 (d, C(3a), C(6a), 3J = 1.5 Hz), 114.0 (d,
CHAr, 3J = 11.4 Hz), 119.2 (s, CHAr), 129.5 (s, CHAr), 146.1 (d,
CAr, 2J = 15.8 Hz). MS (EI), m/z (Irel (%)): 554 [M]+ (6).
Synthesis of Pꢀmonodentate ligands (SC,RP)ꢀ5 and (RC,SP)ꢀ5
(general procedure). A solution of Oꢀbenzylꢀ1,4:3,6ꢀdianhydroꢀ
Dꢀmannitol (1.18 g, 5 mmol) in THF (15 mL) was added
dropwise for 20 min to a vigorously stirred solution of (2R,5S)ꢀ
or (2S,5R)ꢀ2ꢀchloroꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octane (1.21 g, 5 mmol) and Et3N (0.73 mL, 5.2 mmol)
in THF (15 mL) at 20 °C. The resulting mixture was heated to
boiling, refluxed with stirring for 1.5 h, and cooled to 20 °C, and
Et3N·HCl was removed by filtration. The filtrate was evaporated
in vacuo (40 Torr). The products were purified by column
chromatography on silica gel using ethyl acetate as eluent.
3ꢀ[(2R,5S)ꢀ3ꢀPhenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicyclo[3.3.0]octꢀ
2ꢀyloxy]ꢀ6ꢀbenzyloxyꢀ(3R,3aS,6R,6aR)ꢀhexahydrofuro[3,2ꢀb]ꢀ
furan ((SC,RP)ꢀ5). The yield was 1.74 g (79%), yellowish oil.
Found (%): C, 65.69; H, 6.76; N, 6.19. C24H29N2O4P. Calcuꢀ
lated (%): C, 65.44; H, 6.64; N, 6.36. 13C NMR (CDCl3), δ:
26.4 (d, С(7´), 3J = 3.7 Hz), 31.9 (s, C(6´)), 48.2 (d, С(8´),
2J = 37.9 Hz), 54.8 (d, С(4´), 2J = 6.9 Hz), 62.5 (d, С(5´),
2J = 8.4 Hz), 71.0 (s, C(5)), 71.5 (s, C(2)), 72.4 (s, PhCH2O),
2
72.6 (d, C(3), J = 5.5 Hz), 79.6 (s, C(6)), 79.7 (s, C(6a)), 81.6
3
3
(d, C(3a), J = 2.2 Hz), 115.0 (d, CHAr, J = 11.3 Hz), 119.3
(s, CHAr), 127.9 (s, CHAr—Bn), 128.0 (s, CHAr—Bn), 128.5 (s,
CHAr—Bn), 129.2 (s, CHAr), 137.8 (s, CAr—Bn), 145.5 (d, CAr
,
2J = 16.4). MS (EI), m/z (Irel (%)): 441 [M]+ (6).
1,4:3,6ꢀDianhydroꢀDꢀmannitol 7, the starting substrates
dimethyl itaconate 13 and 2ꢀacetamidomethyl acrylate 15, and
3ꢀ[(2S,5R)ꢀ3ꢀPhenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicyclo[3.3.0]octꢀ
2ꢀyloxy]ꢀ6ꢀbenzyloxyꢀ(3R,3aS,6R,6aR)ꢀhexahydrofuro[3,2ꢀb]ꢀ

2318
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 11, November, 2008
Gavrilov et al.
furan ((RC,SP)ꢀ5). The yield was 1.87 г (85%), yellowish oil.
Found (%): C, 65.64; H, 6.73; N, 6.12. Calculated (%):
C, 65.44; H, 6.64; N, 6.36. 13С NMR (CDCl3), δ: 26.2 (d,
С(7´), 3J = 3.7 Hz), 32.0 (s, C(6´)), 48.3 (d, С(8´), 2J = 38.3 Hz),
resulting solution, and the reaction mixture was stirred for 1.5 h
at 20 °C. The precipitate of AgCl formed was separated by
filtration. Solvent excess was removed in vacuo (40 Torr) to a
volume of ~0.5 mL, and ether was added. The precipitate formed
was separated by centrifugation, washed with ether (2×5 mL),
and dried in air and in vacuo (1 Torr).
{3,6ꢀBis[(2R,5S)ꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octꢀ2ꢀyloxy]ꢀ(3R,3aS,6R,6aS)ꢀhexahydrofuro[3,2ꢀb]ꢀ
furanꢀP,P}(πꢀallyl)palladium(2+) tetrafluoroborate ((SC,RP)ꢀ10).
The yield was 92%, light yellow powder, m.p. 126—129 °C
(with decomp.). Found (%): C, 47.45; H, 5.34; N, 7.27.
C31H41BF4N4O4P2Pd. Calculated (%): C, 47.20; H, 5.24; N,
7.10. MS (MALDI TOF/TOF), m/z (Irel (%)): 702 [M – BF4]+
(14), 661 [M – All – BF4]+ (100).
{3,6ꢀBis[(2S,5R)ꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octꢀ2ꢀyloxy]ꢀ(3R,3aS,6R,6aS)ꢀhexahydrofuro[3,2ꢀb]ꢀ
furanꢀP,P}(πꢀallyl)palladium (2+) tetrafluoroborate ((RC,SP)ꢀ10).
The yield was 90%, light yellow powder, m.p. 141—145 °C
(with decomp.). Found (%): C, 47.41; H, 5.30; N, 6.98.
C31H41BF4N4O4P2Pd. Calculated (%): C, 47.20; H, 5.24; N,
7.10. MS (MALDI TOF/TOF), m/z (Irel (%)): 702 [M – BF4]+
(10), 661 [M – All – BF4]+ (100).
Bis{3ꢀ[(2R,5S)ꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octꢀ2ꢀyloxy]ꢀ6ꢀbenzyloxyꢀ(3R,3aS,6R,6aR)ꢀhexahydroꢀ
furo[3,2ꢀb]furanꢀP}(πꢀallyl)palladium(2+) tetrafluoroborate
((SC,RP)ꢀ12). The yield was 92%, light yellow powder,
m.p. 98—101 °C (with decomp.). Found (%): C, 55.12; H, 5.60;
N, 5.18. C51H63BF4N4O8P2Pd. Calculated (%): C, 54.93; H,
5.69; N, 5.02. MS (MALDI TOF/TOF), m/z (Irel (%)): 1028
[M – BF4]+ (5), 987 [M – All – BF4]+ (100).
2
2
54.3 (d, С(4´), J = 7.3 Hz), 63.0 (d, С(5´), J = 8.8 Hz), 71.0
3
(s, C(5)), 71.3 (d, C(2), J = 1.5 Hz), 72.3 (s, PhCH2O), 72.5
2
(d, C(3), J = 5.1 Hz), 79.4 (s, C(6)), 79.8 (s, C(6a)), 81.6 (d,
C(3a), 3J = 1.8 Hz), 114.8 (d, CHAr 3J = 11.7 Hz), 119.1
,
(s, CHAr), 127.7 (s, CHAr—Bn), 127.8 (s, CHAr—Bn), 128.3 (s,
CHAr—Bn), 129.0 (s, CHAr), 137.6 (s, CAr—Bn), 145.2 (d, CAr
,
2J = 16.0 Hz). MS (EI), m/z (Irel (%)): 441 [M]+ (5).
Synthesis of cationic rhodium complexes (SC,RP)ꢀ9, (RC,SP)ꢀ9,
(SC,RP)ꢀ11, and (RC,SP)ꢀ11 (general procedure). A solution
of the corresponding P,Pꢀbidentate or Pꢀmonodentate ligand
(0.1 or 0.2 mmol) in CH2Cl2 (5 mL) was added dropwise for
30 min to a stirred solution of [Rh(COD)2]BF4 (0.041 g,
0.1 mmol) in CH2Cl2 (5 mL) at 20 °C. The reaction mixture
was stirred for more 1 h at 20 °C. Solvent excess was removed
in vacuo (40 Torr) to a volume of ~0.5 mL, and ether was added.
The precipitate formed was separated by centrifugation, washed
with ether (2×5 mL), and dried in air and in vacuo (1 Torr).
{3,6ꢀBis[(2R,5S)ꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octꢀ2ꢀyloxy]ꢀ(3R,3aS,6R,6aS)ꢀhexahydrofuro[3,2ꢀb]ꢀ
furanꢀP,P}(cyclooctaꢀ1,5ꢀdiene)rhodium (1+) tetrafluoroꢀ
borate ((SC,RP)ꢀ9). The yield was 93%, light yellow powder,
m.p. 113—116 °C (with decomp.). Found (%): C, 51.02; H,
5.81; N, 6.62. C36H48BF4N4O4P2Rh. Calculated (%): C, 50.72;
H, 5.68; N, 6.57. MS (ESI), m/z (Irel (%)): 765 [M – BF4]+ (8),
657 [M – COD – BF4]+ (100).
{3,6ꢀBis[(2S,5R)ꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octꢀ2ꢀyloxy]ꢀ(3R,3aS,6R,6aS)ꢀhexahydrofuro[3,2ꢀb]ꢀ
Bis{3ꢀ[(2S,5R)ꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octꢀ2ꢀyloxy]ꢀ6ꢀbenzyloxyꢀ(3R,3aS,6R,6aR)ꢀ
hexahydrofuro[3,2ꢀb]furanꢀP}(πꢀallyl)palladium(2+)
tetrafluoroborate ((RC,SP)ꢀ12). The yield was 95%, sandꢀ
yellow powder, m.p. 104—106 °C (with decomp.). Found (%):
C, 55.17; H, 5.80; N, 4.96. C51H63BF4N4O8P2Pd. Calcuꢀ
lated (%): C, 54.93; H, 5.69; N, 5.02. MS (MALDI TOF/TOF),
m/z (Irel (%)): 1028 [M – BF4]+ (3), 987 [M – All – BF4]+
(100).
furanꢀP,P)(cyclooctaꢀ1,5ꢀdiene)rhodium(1+)
tetrafluoroꢀ
borate ((RC,SP)ꢀ9). The yield was 91%, light yellow powder,
m.p. 132—135 °C (with decomp.). Found (%): C, 50.90; H,
5.76; N, 6.42. C36H48BF4N4O4P2Rh. Calculated (%): C, 50.72;
H, 5.68; N, 6.57. MS (EI), m/z (Irel (%)): 765 [M – BF4]+ (11),
657 [M – COD – BF4]+ (100).
Bis(3ꢀ[(2R,5S)ꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octꢀ2ꢀyloxy]ꢀ6ꢀbenzyloxyꢀ(3R,3aS,6R,6aR)ꢀhexaꢀ
hydrofuro[3,2ꢀb]furanꢀP)(cyclooctaꢀ1,5ꢀdiene)rhodium(1+)
tetrafluoroborate ((SC,RP)ꢀ11). The yield was 89%, yellow
powder, m.p. 102—105 °C (with decomp.). Found (%): C, 57.21;
H, 5.90; N, 4.85. C56H70BF4N4O8P2Rh. Calculated (%):
C, 57.06; H, 5.99; N, 4.75. MS (ESI), m/z (Irel (%)): 984
[M – COD – BF4]+ (100), 543 [M – COD – BF4 – L]+ (11).
Bis(3ꢀ[(2S,5R)ꢀ3ꢀphenylꢀ1,3ꢀdiazaꢀ2ꢀphosphabicycloꢀ
[3.3.0]octꢀ2ꢀyloxy]ꢀ6ꢀbenzyloxyꢀ(3R,3aS,6R,6aR)ꢀ
hexahydrofuro[3,2ꢀb]furanꢀP)(cyclooctaꢀ1,5ꢀdiene)rhodium(1+)
tetrafluoroborate ((RC,SP)ꢀ11). The yield was 95%, yellow
powder, m.p. 117—120 °C (with decomp.). Found (%): C, 57.30;
H, 6.10; N, 4.64. C56H70BF4N4O8P2Rh. Calculated (%):
C, 57.06; H, 5.99; N, 4.75. MS (ESI), m/z (Irel (%)): 984
[M – COD – BF4]+ (100), 543 [M – COD – BF4 – L]+ (16).
Synthesis of cationic palladium complexes (SC,RP)ꢀ10,
(RC,SP)ꢀ10, (SC,RP)ꢀ12, and (RC,SP)ꢀ12 (general procedure).
A solution of the corresponding P,Pꢀbidentate or Pꢀmonodentate
ligand (0.2 or 0.4 mmol) in CH2Cl2 (7 mL) was added dropꢀ
wise for 30 min to a stirred solution of [Pd(All)Cl]2 (0.037 g,
0.1 mmol) in CH2Cl2 (5 mL) at 20 °C. The reaction mixture was
stirred for 1 h more at 20 °C. A solution of AgBF4 (0.2 mmol,
0.039 g) in THF (5 mL) was added dropwise for 30 mL to the
This work was financially supported by the INTAS
(Grant 05ꢀ1000008ꢀ8064) and the Russian Foundation
for Basic Research (Project No. 08ꢀ03ꢀ00416ꢀa).
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Received May 13, 2008;
in revised form July 4, 2008