Synthesis and transformations of metallacycles 32. Novel method for the synthesis of cyclopentanols from aluminacyclopentanes

Article abstract of DOI:10.1023/B:RUCB.0000024841.74897.c2

Cyclopentanols were synthesized by a one-pot method involving Cp₂ZrCl₂-catalyzed cycloalumination of α-olefins with trialkylalanes followed by the in situ reactions of aluminacyclopentanes with esters in the presence of catalytic amounts of Cu, Ni or Pd salts and complexes.

Full text of DOI:10.1023/B:RUCB.0000024841.74897.c2

Russian Chemical Bulletin, International Edition, Vol. 53, No. 1, pp. 133—136, January, 2004
133
Synthesis and transformations of metallacycles
32.* Novel method for the synthesis of cyclopentanols
from aluminacyclopentanes
U. M. Dzhemilev,ꢀ A. G. Ibragimov, L. O. Khafizova, R. R. Gilyazev, and V. A. D´yakonov
Institute of Petrochemistry and Catalysis, Bashkortostan Republic Academy of Sciences
and Ufa Research Center of the Russian Academy of Sciences,
141 prosp. Oktyabrya, 450075 Ufa, Russian Federation.
Fax: +7 (347 2) 31 2750. Eꢀmail: ink@anrb.ru
Cyclopentanols were synthesized by a "oneꢀpot" method involving Cp2ZrCl2ꢀcatalyzed
cycloalumination of αꢀolefins with trialkylalanes followed by the in situ reactions of
aluminacyclopentanes with esters in the presence of catalytic amounts of Cu, Ni or Pd salts and
complexes.
Key words: cyclopentanols, olefins, cycloalumination, aluminacyclopentanes, catalysis,
esters.
Cyclopentanols and their derivatives are intermediate
products in the synthesis of perfumes and medicines.2—4
Along with familiar routes to cyclopentanols (reduction
of cyclopentanones, hydration of cyclopentenes, etc.),
reactions of in situ formed 1,4ꢀdimagnesium compounds
with esters attract attention.5—7 In these reactions, cycloꢀ
pentanols have been selectively obtained from compounds
containing no cyclopentane fragments. However, 1,4ꢀdiꢀ
magnesium compounds are not easily accessible, which
limits the synthetic value of these reactions.
to selectively give, upon hydrolysis of the reaction
mixture, 3ꢀ(nꢀalkyl)cyclopentanols 3a,b in ∼75% yield
(Scheme 1). Apparently, the reaction mechanism includes
generation of an intermediate carbocation center at the
orthoester C atom of OAC, its stabilization by intramoꢀ
Scheme 1
With the aim of developing a "oneꢀpot" method for
the synthesis of cyclopentanols from accessible αꢀolefins
and extending the area of application of cyclic organoꢀ
aluminum compounds (OAC)8,9 in synthetic practice, we
studied the reactions of in situ formed aluminacycloꢀ
pentanes (ACP) with esters in the presence of salts and
complexes of transition metals.
Results and Discussion
Trialkylalanes are known10 to react with esters at elꢀ
evated temperature (35—80 °C) to give a mixture of priꢀ
mary, secondary, and tertiary alcohols and ketones. Reꢀ
action products and their total yield depend on the strucꢀ
ture of the starting OAC, the reaction temperature, and
the reagent ratio.
1—3
R1
R2
a
Bun
H
b
c
d
nꢀC6H13 nꢀC6H13 nꢀC6H13
H
Me
Et
We found that ACP 1a,b prepared in situ by
Cp2ZrCl2ꢀcatalyzed cycloalumination of αꢀolefins
(hexꢀ1ꢀene and octꢀ1ꢀene) with Et3Al react with alkyl
formates in the presence of 10 mol.% CuCl (20 °C, 7 h)
1—3
e
f
g
h
R1
R2
Ph
H
CH2Ph
H
CH2Ph
Et
H
* For Part 31, see Ref. 1.
R3 = Alk
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 130—133, January, 2004.
1066ꢀ5285/04/5301ꢀ0133 © 2004 Plenum Publishing Corporation

134
Russ.Chem.Bull., Int.Ed., Vol. 53, No. 1, January, 2004
Dzhemilev et al.
Table 1. Effect of the catalyst nature on the yield
of cyclopentanol 3b (ACP : HCO2Et = 1 : 3,
a catalyst (10 mol.%), hexane, 20 °C, 7 h)
Scheme 2
Entry
Catalyst
Yield of 3b (%)
1
2
3
4
5
6
7
8
9
10
CuCl
CuI
Cu(acac)2 + 2 Ph3P
ZrCl4
Ni(acac)2 + 2 Ph3P
NiCl2 + 2 Ph3P
PdCl2 + 2 Ph3P
NiCl2
76
70
37
30
43
38
32
25
20
—
PdCl2
—
lecular ring isomerization into aluminum alkoxides 2, and
hydrolysis of the latter to form target cyclopentanols 3.
In situ formed ACP 1 react with esters of organic acids
(acetic and propionic) or with acetyl chloride or bromide
to give 1,3ꢀdialkylcyclopentanols 3c,d (see Scheme 1).
The longer the alkyl substituent at the carbonyl C
atom in the ester, the lower the yields of the correspondꢀ
ing cyclopentanols. Among the salts and complexes of
transition metals (Cu, Ni, Pd, and Zr) we used in the
cyclization, copper compounds proved to be most active
(Table 1). The reactions were carried out in hexane beꢀ
cause the yields of the target products in other (aromatic
and ethereal) solvents were lower (Table 2).
4, 5: ∆3 (a), ∆4 (b)
Scheme 3
The developed "oneꢀpot" synthesis opens a conveꢀ
nient route to cyclopentanols, their structures being mainly
determined by the starting olefins. Under our reacꢀ
tion conditions (10 mol.% CuCl, 20 °C, 7 h, hexane),
cyclopentanols 3e—h and 5a,b were obtained from vinylꢀ
cyclohexene, styrene, allylbenzene, and dicyclopentaꢀ
diene (in the last case, the reaction proceeds through
OAC 4a,b (Scheme 2)).
7
R1
R2
a
b
c
d
Bun
Et
Bun nꢀC6H13 Bun
Me
H
H
The reactions of in situ formed11 transꢀ3,4ꢀdialkylꢀ
aluminacyclopentanes 6 with alkyl carboxylates afford
cyclopentanols 7, in which the alkyl substituents are also
trans (Scheme 3).
Thus, our "oneꢀpot" method for the synthesis of cyclic
alcohols involves cycloalumination of olefins with triꢀ
R3 = Alk; [Zr] = ZrCl4, Cp2ZrCl2
alkylalanes followed by the in situ reaction of the resulting
aluminacyclopentanes with alkyl carboxylates in the presꢀ
ence of transition metal salts or complexes to give, upon
hydrolysis of the reaction mixture, desired cyclopentanols.
Table 2. Effect of the solvent nature on the yield
of cyclopentanol 3b (ACP : HCO2Et = 1 : 3,
CuCl (10 mol.%), 20 °C, 7 h)
Experimental
Reactions with organometallic compounds were carried out
in a flow of dry argon. Solvents were dried and distilled immediꢀ
ately before use. Commercially available 95% Et3Al was used.
Reaction products were analyzed on a Chromꢀ5 chromatograph
in a helium flow (column 1200×3 mm, 5% SEꢀ30). IR spectra
were recorded on an IR75 spectrometer (thin film). Mass specꢀ
tra were recorded on a MXꢀ1306 spectrometer (70 eV, 200 °C).
1H and 13C NMR spectra were recorded on Jeol FXꢀ90 Q inꢀ
Entry
Solvent
Yield of 3b (%)
1
2
3
4
5
Hexane
Toluene
Benzene
THF
76
54
52
10
9
Ether

Novel route to cyclopentanols
Russ.Chem.Bull., Int.Ed., Vol. 53, No. 1, January, 2004
135
strument (89.55 (1H) and 22.5 MHz (13C)) in CDCl3. The yields
of the products were determined by GLC.
13C NMR, δ: 25.26 (C(10)); 27.60, 27.82 (C(4)); 28.52 (C(11));
30.73 (C(7)); 35.32, 35.68 (C(6)); 37.32, 37.68 (C(5)); 39.16,
39.39 (C(3)); 43.07, 43.50 (C(2)); 75.81, 76.18 (C(1)); 126.50
(C(8)); 127.18 (C(9)). MS, m/z (Irel (%)): 166 [M+] (0.72), 148
(17.79), 134 (0.57), 122 (1.06), 108 (1.91), 94 (8.55), 81 (39.84),
80 (100), 58 (1.29), 44 (1.95), 30 (1.00), 29 (18.01).
3ꢀPhenylcyclopentanols (3f)*. Yield 64%, Rf 0.52. Found (%):
C, 81.23; H, 8.52. C11H14O. Calculated (%): C, 81.44; H, 8.70.
IR, ν/cm–1: 3380, 3015, 2990, 2950, 2840, 1710, 1490, 1450,
1395, 1180, 750, 700. 1H NMR, δ: 1.45—2.25 (m, 6 H, CH2);
3.10—3.25 (m, 1 H, CH—Ph); 4.40 (m, 1 H, CH—OH);
7.00—7.50 (m, 5 H, Ph). 13C NMR, δ: 28.91, 29.20 (C(4));
32.65, 33.49 (C(5)); 35.65, 36.01 (C(3)); 43.95, 44.25 (C(2));
73.51, 73.75 (C(1)); 126.04 (C(9)); 127.08 (C(7)); 127.53 (C(8),
C(10)); 128.48 (C(11)); 141.62 (C(6)). MS, m/z (Irel (%)): 162
[M]+ (31.87), 145 (9.42), 144 (100), 143 (52.88), 118 (25.89),
104 (53.75), 90 (2.04), 77 (29.56), 29 (17.74).
CuClꢀcatalyzed reactions of 3ꢀsubstituted 1ꢀethylꢀACP with
esters (general procedure). Cp2ZrCl2 (0.5 mmol), hexane (3 mL),
an olefin (10 mmol), and Et3Al (12 mmol) were placed in a glass
reaction vessel under dry argon at 0 °C. The reaction mixture
was warmed to ∼20 °C and stirred for 12 h. At –15 °C, CuCl
(1 mmol) was added and then an ester (30 mmol) was slowly
added dropwise. The reaction mixture was allowed to warm to
∼20 °C, stirred for 8 h, and hydrolyzed with aqueous 8—10%
HCl. The organic material was extracted with ether or hexane,
and the extracts were dried with CaCl2. The products were isoꢀ
lated by column chromatography (silica gel L 40/100 µm, hexꢀ
ane—Et2O (10 : 1) as the eluent).
3ꢀ(nꢀButyl)cyclopentanols (3a)*. Yield 76%, Rf 0.45.
Found (%): C, 75.82; H, 12.63. C9H18O. Calculated (%):
C, 76.00; H, 12.76. IR, ν/cm–1: 3355, 2985, 2950, 2840, 1730,
1450, 1385, 1230, 1030, 925, 730. 1H NMR, δ: 0.90 (t, 3 H, Me,
J = 6.0 Hz); 1.15—1.52 (m, 6 H, CH2); 1.78—2.35 (m, 7 H, CH,
CH2 (ring)); 4.29 (m, 1 H, CH—OH). 13C NMR, δ: 14.50
(C(9)); 22.74 (C(8)); 30.28 (C(7)); 30.78, 30.86 (C(4)); 32.08,
32.79 (C(6)); 35.97, 36.05 (C(5)); 37.84, 37.98 (C(3)); 39.95
(C(2)); 76.47, 76.82 (C(1)). MS, m/z: 124 [M – 18]+.
3ꢀ(nꢀHexyl)cyclopentanols (3b)*. Yield 75%, Rf 0.46.
Found (%): C, 77.39; H, 12.84. C11H22O. Calculated (%):
C, 77.58; H, 13.02. IR, ν/cm–1: 3380, 2990, 2950, 2840, 1720,
1460, 1380, 1185, 1030, 950, 720. 1H NMR, δ: 0.91 (t, 3 H, Me,
J = 6.0 Hz); 1.18—1.51 (m, 10 H, CH2); 1.78—2.35 (m, 7 H,
CH, CH2 (ring)); 4.30 (m, 1 H, CH—OH). 13C NMR, δ: 14.06
(C(11)); 22.62 (C(10)); 29.46 (C(8)); 28.49 (C(7)); 30.57, 30.66
(C(4)); 31.87 (C(9)); 32.20, 32.96 (C(6)); 35.77, 35.86 (C(5));
36.52, 37.90 (C(3)); 39.62 (C(2)); 76.55, 76.95 (C(1)). MS,
m/z (Irel (%)): 152 [M – 18]+ (5.26), 112 (1.52), 85 (2.48), 71
(2.63), 67 (100), 57 (16.28), 43 (31.01), 29 (27.50).
3ꢀ(nꢀHexyl)ꢀ1ꢀmethylcyclopentanols (3c)*. Yield 68%,
Rf 0.59. Found (%): C, 78.02; H, 13.01. C12H24O. Calcuꢀ
lated (%): C, 78.19; H, 13.13. IR, ν/cm–1: 3350, 2990, 2950,
2840, 1720, 1460, 1380, 1235, 1100, 1030, 1000, 925, 900, 730,
700. 1H NMR, δ: 0.90 (t, 3 H, Me, J = 6.0 Hz); 1.20—1.58 (m,
10 H, CH2); 1.33 (s, 3 H, Me); 1.61—2.51 (m, 7 H, CH,
CH2 (ring)). 13C NMR, δ: 14.07 (C(11)); 22.67 (C(10)); 28.52,
28.78 (C(12)); 29.50, 29.56 (C(7), C(8)); 31.19, 31.45 (C(4));
31.90 (C(9)); 36.52, 36.98 (C(6)); 38.41, 39.06 (C(3)); 40.75,
41.59 (C(5)); 48.23, 48.62 (C(2)); 79.74, 79.96 (C(1)). MS,
m/z: 184 [M]+.
3ꢀBenzylcyclopentanols (3g)*. Yield 69%, Rf 0.53. Found (%):
C, 81.57; H, 8.98. C12H16O. Calculated (%): C, 81.77; H, 9.15.
IR, ν/cm–1: 3380, 2990, 3015, 2995, 2950, 1715, 1600, 1490,
1450, 1400, 1180, 750, 700. 1H NMR, δ: 1.58—2.25 (m, 7 H,
CH, CH2); 2.62 (d, 2 H, CH2—Ph, J = 5.6 Hz); 4.28 (m, 1 H,
CH—OH); 7.00—7.48 (m, 5 H, Ph). 13C NMR, δ: 30.34, 30.54
(C(4)); 32.09, 32.39 (C(5)); 38.78, 39.36 (C(3)); 39.72, 40.33
(C(5)); 41.60, 42.06 (C(2)); 76.38, 76.57 (C(1)); 126.00 (C(10));
128.24 (C(8), C(12)); 128.42 (C(9), C(11)); 141.38 (C(7)).
3ꢀBenzylꢀ1ꢀethylcyclopentanols (3h)*. Yield 55%, Rf 0.64.
Found (%): C, 82.09; H, 9.23. C14H20O. Calculated (%):
C, 82.30; H, 9.87. IR, ν/cm–1: 3360, 3015, 2960, 2905, 1710,
1600, 1490, 1450, 1400, 730, 700. 1H NMR, δ: 0.92 (t, 3 H, Me,
J = 6.0 Hz); 1.10—2.20 (m, 9 H, CH, CH2); 2.38—2.90 (m,
1 H, CH—Ph); 6.98—7.50 (m, 5 H, Ph). 13C NMR, δ: 8.62,
8.82; 30.73, 31.38; 34.57; 38.60, 39.64; 39.90, 41.01; 42.24, 42.83;
45.69, 46.34; 82.27, 82.76; 125.68, 128.21, 128.73, 141.74.
Tetracyclo[5.5.1.02,6.08,12]tridecꢀ3ꢀenꢀ11ꢀol (5a) and tetraꢀ
cyclo[5.5.1.02,6.08,12]tridecꢀ4ꢀenꢀ11ꢀol (5b) (∼1 : 1). Yield 65%,
Rf 0.51. Found (%): C, 81.95; H, 9.49. C13H18O. Calculated (%):
C, 82.06; H, 9.53. 1H NMR, δ: 1.08—2.48 (m, 14 H, CH2, CH);
5.48—5.66 (m, 2 H, CH=CH); 4.34 (m, 1 H, CH—OH).
13C NMR, δ: 5a: 26.53 (C(9)), 31.97 (C(13)), 33.17 (C(5)),
38.02 (C(1)), 39.65 (C(10)), 40.72 (C(7)), 41.72 (C(6)), 42.16
(C(8)), 45.51 (C(12)), 53.29 (C(2)), 75.42 (C(11)), 130.14
(C(4)), 132.51 (C(3)); 5b: 26.53 (C(9)), 31.57 (C(13)), 32.97
(C(3)), 36.17 (C(12)), 38.02 (C(1)), 39.65 (C(10)), 41.41 (C(7)),
42.16 (C(8)), 43.78 (C(2)), 51.92 (C(6)), 75.30 (C(11)), 130.76
(C(4)), 132.23 (C(5)).
Reactions of transꢀ3,4ꢀdisubstituted 1ꢀalkylꢀACP with esꢀ
ters. A solution of a corresponding R3Al (10 mmol) was preꢀ
pared according to a known procedure and placed in a glass
reaction vessel under argon.10 Copper(I) chloride (1 mmol) was
added at –15 °C, and then an ester (30 mmol) was slowly added
dropwise. The reaction was carried out and the reaction products
were isolated as described above for 3ꢀsubstituted 1ꢀethylꢀACP.
transꢀ3,4ꢀDibutylcyclopentanol (7a). Yield 75%, Rf 0.61.
Found (%): C, 78.53; H, 13.01. C13H26O. Calculated (%):
C, 78.72; H, 13.21. IR, ν/cm–1: 3350, 2985, 2845, 1725, 1450,
1385, 1230, 1030, 925, 730. 1H NMR, δ: 0.86—0.90 (m, 6 H,
Me); 1.15—1.30 (m, 12 H, CH2); 1.65—2.35 (m, 6 H, CH, CH2
(ring)); 4.30 (m, 1 H, CH—OH). 13C NMR, δ: 14.12 (C(9),
C(13)); 22.66 (C(8), C(12)); 29.85 (C(7), C(11)); 34.35 (C(6),
C(10)); 39.10 (C(3), C(4)); 42.02 (C(2), C(5)); 73.25 C(1).
1ꢀEthylꢀ3ꢀ(nꢀhexyl)cyclopentanols (3d)*. Yield 60%, Rf 0.52.
Found (%): C, 78.51; H, 13.04. C13H26O. Calculated (%):
C, 78.72; H, 13.21. IR, ν/cm–1: 3350, 2990, 2950, 2840, 1720,
1450, 1380, 1230, 1030, 920, 730. 1H NMR, δ: 0.83—1.02 (m,
6 H, Me); 1.20—1.57 (m, 12 H, CH2); 1.61—2.51 (m, 7 H, CH,
CH2 (ring)). 13C NMR, δ: 8.49, 8.72 (C(13)); 14.00 (C(11));
22.68 (C(10)); 28.48, 29.49 (C(7), C(8)); 30.86, 31.38 (C(4));
31.87 (C(9)); 34.41, 34.47 (C(12)); 36.33, 36.37 (C(6)); 36.95,
37.14 (C(5)); 38.02, 38.57 (C(3)); 46.00, 46.45 (C(2)); 82.31,
82.80 (C(1)). MS, m/z: 198 [M]+.
3ꢀCyclohexenylcyclopentanols (3e)*. Yield 65%, Rf 0.68.
Found (%): C, 79.28; H, 10.70. C11H18O. Calculated (%):
C, 79.46; H, 10.91. 1H NMR, δ: 1.60—2.21 (m, 14 H, CH,
CH2); 4.28 (m, 1 H, CH—OH); 5.15—5.75 (m, 2 H, CH=CH).
* A mixture of cisꢀ and transꢀisomers (∼2 : 1).

136
Russ.Chem.Bull., Int.Ed., Vol. 53, No. 1, January, 2004
Dzhemilev et al.
transꢀ3,4ꢀDi(nꢀhexyl)cyclopentanol (7b). Yield 74%, Rf 0.60.
Nauk, Ser. Khim., 2003, 2302 [Russ. Chem. Bull., Int. Ed.,
2003, 52, 2434].
2. J. S. Cha and O. O. Kwon, J. Org. Chem., 1997, 62, 3019.
3. K. V. Lebedeva, V. A. Minyailo, and Yu. B. Pyatnova,
Feromony nasekomykh [Insect Pheromones], Nauka, Mosꢀ
cow, 1984, 189 pp. (in Russian).
4. I. N. Bratus, Khimiya dushistykh veshchestv [The Chemistry of
Perfumes], Pishchevaya promꢀst´, Moscow, 1979, 304 pp.
(in Russian).
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Found (%): C, 80.03; H, 13.19. C17H34O. Calculated (%):
C, 80.24; H, 13.47. 1H NMR, δ: 0.88—0.91 (m, 6 H, Me);
1.15—1.30 (m, 20 H, CH2); 1.65—2.35 (m, 6 H, CH,
CH2 (ring)); 4.30 (m, 1 H, CH—OH). 13C NMR, δ: 14.15
(C(11), C(17)); 22.54 (C(10), C(16)); 26.15 (C(7), C(13)); 29.42
(C(8), C(14)); 31.72 (C(9), C(15)); 34.31 (C(6), C(12)); 39.02
(C(3), C(4)); 41.45 (C(2), C(5)); 72.18 (C(1)).
transꢀ3,4ꢀDi(nꢀbutyl)ꢀ1ꢀmethylcyclopentanol (7c). Yield
73%, Rf 0.68. Found (%): C, 78.98; H, 13.11. C14H28O. Calcuꢀ
1
lated (%): C, 79.18; H, 13.29. H NMR, δ: 0.83—0.95 (m, 6 H,
Me); 1.14—1.29 (m, 12 H, CH2); 1.32 (s, 3 H, Me); 1.65—2.35
(m, 6 H, CH, CH2 (ring)). 13C NMR, δ: 14.12 (C(9), C(13));
22.69 (C(8), C(12)); 26.92 (C(14)); 31.93 (C(7), C(11));
34.53 (C(6), C(10)); 38.15 (C(3), C(4)); 41.94 (C(2), C(5));
72.83 (C(1)).
transꢀ3,4ꢀDi(nꢀbutyl)ꢀ1ꢀethylcyclopentanol (7d). Yield 69%,
Rf 0.71. Found (%): C, 79.37; H, 13.20. C15H30O. Calcuꢀ
lated (%): C, 79.58; H, 13.36. 1H NMR, δ: 0.86—0.92 (m, 9 H,
Me); 1.24—1.62 (m, 14 H, CH2); 1.67—2.54 (m, 6 H, CH,
CH2 (ring)). 13C NMR, δ: 8.80 (C(15)); 14.11 (C(9), C(13));
22.69 (C(8), C(12)); 29.95 (C(7), C(11)); 32.42 (C(14));
33.90 (C(6), C(10)); 37.41 (C(3), C(4)); 38.44 (C(2), C(5));
76.65 (C(1)).
6. C. D. Nenitzescu and I. Necsoiu, J. Am. Chem. Soc., 1950,
72, 3483.
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Zelenova, and U. M. Dzhemilev, Zh. Org. Khim., 1985, 21,
259 [J. Org. Chem. USSR, 1985, 21 (Engl. Transl.)].
8. U. M. Dzhemilev and A. G. Ibragimov, Usp. Khim.,
2000, 69, 134 [Russ. Chem. Rev., 2000, 69, 121 (Engl.
Transl.)].
9. U. M. Dzhemilev and A. G. Ibragimov, Izv. Akad. Nauk,
Ser. Khim., 1998, 816 [Russ. Chem. Bull., 1998, 47, 786 (Engl.
Transl.)].
10. G. A. Tolstikov and V. P. Yur´ev, Alyuminiiorganicheskii
sintez [Organoaluminum Synthesis], Nauka, Moscow, 1979,
290 pp. (in Russian).
11. U. M. Dzhemilev, A. G. Ibragimov, A. B. Morozov, R. R.
Muslukhov, and G. A. Tolstikov, Izv. Akad. Nauk SSSR,
Ser. Khim., 1991, 1607 [Bull. Acad. Sci. USSR, Div. Chem.
Sci., 1991, 40, 1425 (Engl. Transl.)].
This work was financially supported by the Russian
Foundation for Basic Research (Project Nos. 02ꢀ03ꢀ
97903a and 03ꢀ03ꢀ33050a).
References
1. A. G. Ibragimov, L. O. Khafizova, G. N. Gil´fanova, L. R.
Yakupova, A. L. Borisova, and U. M. Dzhemilev, Izv. Akad.
Received July 30, 2003