Straightforward regio- and stereo-selective synthesis of t-2-[(diphenylphosphinoyl)methyl]-c-3-(disubstitutedphosphinoyl)-r-1- cyclopentanols

Article abstract of DOI:10.1016/S0040-4020(02)00314-9

A 3-step, regio- and stereo-selective, high-yielding synthesis of t-2-[(diphenylphosphinoyl)methyl]-c-3-(disubstitutedphosphinoyl)-r-1- cyclopentanols (8a-d) is described. Reaction of epoxides 2a-d and/or 5a-d with the lithium derivative of methyldiphenylphosphine oxide (9) gave cyclopentanols 8a-d. Base-catalyzed rearrangement of epoxides 2a-d and/or 5a-d led to 3-(disubstitutedphosphinoyl)cyclopent-2-en-1-ols (7a-d) which on reaction with the lithium derivative of 9 gave also 8a-d. The relative configurations of 2a and 8b-d were obtained by single crystal X-ray diffraction analysis.

Full text of DOI:10.1016/S0040-4020(02)00314-9

TETRAHEDRON
Pergamon
Tetrahedron 58 22002) 3473±3484
Straightforward regio- and stereo-selective synthesis
of t-2-[ꢀdiphenylphosphinoyl)methyl]-c-3-
ꢀdisubstitutedphosphinoyl)-r-1-cyclopentanols
a,p
a
b
a
Pelayo Camps, Gisela Colet, Merce Font-Bardia, Victoria MunÄoz-Torrero, Xavier Solans
b
Á
and Santiago Vazquez
a
Â
a
 Á Á
Laboratori de Quõmica Farmaceutica, Facultat de Farmacia, Universitat de Barcelona, Av. Diagonal 643, E-08028 Barcelona, Spain
b
Á Â Â
Departament de Cristallogra®a i Diposits Minerals, Facultat de Geologia, Universitat de Barcelona, Av. Martõ i Franques,
E-08028 Barcelona, Spain
Received 21 January 2002; revised 28 February 2002; accepted 15 March 2002
AbstractÐA 3-step, regio- and stereo-selective, high-yielding synthesis of t-2-[2diphenylphosphinoyl)methyl]-c-3-2disubstitutedphosphi-
noyl)-r-1-cyclopentanols 28a±d) is described. Reaction of epoxides 2a±d and/or 5a±d with the lithium derivative of methyldiphenyl-
phosphine oxide 29) gave cyclopentanols 8a±d. Base-catalyzed rearrangement of epoxides 2a±d and/or 5a±d led to 3-2disubsti-
tutedphosphinoyl)cyclopent-2-en-1-ols 27a±d) which on reaction with the lithium derivative of 9 gave also 8a±d. The relative con®gurations
of 2a and 8b±d were obtained by single crystal X-ray diffraction analysis. q 2002 Elsevier Science Ltd. All rights reserved.
1. Introduction
to give g-2hydroxyalkyl)phosphine oxides in good yields.3
Thus, we imagined the synthesis of diphosphines of general
structure 1 by regioselective opening of trans-epoxides 2
which could be obtained from 22-cyclopentenyl)phosphine
oxides 23) 2Fig. 1).
Application of chiral diphosphine ligands in transition
metal-catalyzed asymmetric processes has been extensively
studied in the past two decades.1 This activity has led to the
discovery of a number of highly enantioselective chiral
phosphine-based catalysts which have been used in the
pharmaceutical industry for the synthesis of enantiopure
drugs.2
2. Results and discussion
Reaction of an excess of 22-cyclopentenyl)magnesium
chloride 24) with diphenyl- or dialkyl-chlorophosphines
gave, after air oxidation, phosphine oxides 3a±d, in medium
to high yields.4
As part of our interest on the synthesis and applications in
asymmetric catalysis of 1,4-diphosphines we planned the
synthesis of a series of diphosphines of general structure 1
2Fig. 1). The hydroxyl group of compounds 1 could be of
interest to develop polymer-based chiral ligands and to
separate the racemic mixture via diastereomeric derivatives
at an appropriate stage of the synthesis.
Epoxidation of 3a±d with m-chloroperbenzoic acid
2m-CPBA)5 gave a stereoisomeric mixture of the corre-
sponding epoxides 2a±d and 5a±d in quantitative yields,
which could be easily separated by column chromato-
graphy, the trans stereoisomer being always the main
component. The trans arrangement of 2a was established
by spectroscopic means and by single crystal X-ray diffrac-
tion analysis, while in the case of 2b±d, comparison of their
1H and 13C NMR data with those of 2a was conclusive.
Several of these epoxides crystallized in hydrated form, as
it was shown by their elemental analyses.
Lithiated alkyldiphenylphosphine oxides react with epoxides
Figure 1. Retrosynthetic analysis of diphosphine 1.
Keywords: phosphine oxides; Michael reaction; epoxide.
Corresponding author. Tel.: 134-93-402-4536; fax: 134-93-403-5941;
When epoxide 2c hemihydrate was reacted for the ®rst time
with the lithium derivative of methyldiphenylphosphine
oxide 29), generated from 9 21 equiv.) and an excess of
n-butyllithium 21.6 equiv.) in anhydrous THF, allylic alco-
hol 7c 219% yield) and starting 9 291% yield) were the only
p
e-mail: camps@farmacia.far.ub.es
0040±4020/02/$ - see front matter q 2002 Elsevier Science Ltd. All rights reserved.
PII: S0040-4020202)00314-9

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P. Camps et al. / Tetrahedron 58 42002) 3473±3484
dioxide was obtained 267% yield), whose 1H and 13C
NMR spectra showed it not to be the expected product 6c,
but the isomeric 3-2diisopropylphosphinoyl)-2-[2diphenyl-
phosphinoyl)methyl]-1-cyclopentanol. Although the relative
con®guration of this compound could not be deduced from
the NMR data, the single crystal X-ray diffraction analysis
showed it to be the 2t-2,c-3,r-1)-stereoisomer 28c).
Moreover, the same product 8c was obtained 292% yield) on
reaction of the stereoisomeric anhydrous compound 5c, with
the lithium derivative of 9. The fact that the same product 8c
was obtained starting whether from 2c or 5c suggests that
both reactions occur through a common intermediate.
Taking into account the isolation of the allylic alcohol 7c
as a byproduct, the lithium derivative of 7c could be the
common intermediate in these reactions, whose conversion
to 8c might take place regioselectively through a Michael
addition of the lithium derivative of 9 to the b-position of
the lithium salt of the unsaturated a,b-phosphine oxide
7c. The stereoselectivity of this addition could be ®rst
kinetically controlled by the lithiated hydroxy group of 7c
2anti-addition) followed by thermodynamically controlled
protonation of the intermediate a-phosphinoyl carbanion6
to give the more stable 2t-2,c-3,r-1)-8c. When allylic alcohol
7c was reacted with the lithium derivative of 9 under similar
reaction conditions, 8c was obtained 256% yield), thus
con®rming the hypothesis of the intermediacy of the lithium
derivative of 7c in the conversions of 2c and 5c to 8c
2Scheme 1).
Scheme 1. Reagents and conditions: 2a) R2PCl, anh. THF, 08C; 2b) air;
2c) m-CPBA 220% molar excess), CH2Cl2, 258C, 18 h; 2d) KOH, EtOH,
258C, 18 h; 2e) lithium derivative of methyldiphenyphosphine oxide 29)
2from 9 in anh. THF and 1.6 M n-BuLi in hexanes).
isolated products, after column chromatography of the crude
reaction mixture. Since no other products derived from
epoxide 2c were isolated, the low yield of 7c might be
associated to its high polarity that would make dif®cult its
extraction from the aqueous phase. Formation of 7c could be
explained by abstraction of the acidic cyclopentyl a-phos-
phinoyl proton followed by cleavage of the vicinal C±O
bond.6 This transformation could be induced by any base
present in the reaction medium. In fact, the allylic alcohol 7c
was obtained in good yield when the above reaction was
carried out in the absence of 9. Also, reaction of 2c with
ethanolic KOH gave 7c in 98% yield. The same product 7c
was also obtained 295% yield) on treatment of the stereo-
isomeric epoxide 5c with ethanolic KOH.
Similarly, reaction of the anhydrous trans-epoxide 2b with
the lithium derivative of 9 gave, after column chroma-
tography, diphosphine dioxide 8b 274% yield) and allylic
alcohol 7b 214% yield). Compound 8b was alternatively
obtained in high yield by reaction of 7b with the lithium
derivative of 9. Alcohol 7b was isolated in low yield 227%)
from the reaction of 2b with n-butyllithium and in excellent
yield 298%) from 5b by reaction with ethanolic KOH.
When anhydrous epoxide 2c 2azeotropic distillation of
water with toluene in a Dean±Stark equipment) was reacted
with the lithium derivative of 9 as before, a diphosphine
Also, compounds 8a and 8d were obtained in good yields
287.5 and 95%, respectively) by reaction of the stereo-
isomeric mixtures of epoxides 2a/5a and 2d/5d with the
lithium derivative of 9. Alternatively, the above mixtures
of epoxides were transformed into the corresponding allylic
alcohols 7a and 7d 299 and 76% yield, respectively) by
reaction with ethanolic KOH which, on treatment with the
lithium derivative of 9, gave 8a and 8d 287 and 90% yield,
respectively).
The relative con®gurations of compounds 8b and 8d were
obtained by X-ray diffraction analysis, while that of 8a was
assigned by comparison of its NMR data with those of 8b
and 8d.
1
Assignment of the H and 13C NMR spectra of the new
compounds herein described was carried out on the basis
of the COSY H/1H, COSY H/13C, NOESY and DEPT
experiments. In the cases of compounds 3a±d and 7a±d,
assignment was straightforward. Differentiation of the
stereoisomeric epoxides 2a±d from 5a±d was carried out
by comparison of the NMR data of each compound with
those of 2a, whose trans-arrangement was established by
single crystal X-ray diffraction analysis 2Fig. 2).
1
1
Figure 2. X-Ray diffraction structure 2ORTEP) of 2a.

P. Camps et al. / Tetrahedron 58 42002) 3473±3484
3475
3
Table 1. Signi®cant J213C±31P) values for compounds 5a±d
equatorial arrangement were correct, the 3J213C±31P)
coupling constant values of C3 and C4 must be much higher
because the C3±C2±C1±P and C4±C5±C1±P dihedral
angles would be close to 1808. In fact, this is the case, as
3J213C±31P)
5a
5b
5c
5d
C3±P
C4±P
6.6
9.7
9.0
10.6
8.8
10.6
10.9
10.3
3
can be seen from the J213C±31P) values corresponding to
C3 and C4 of 5a±d, collected in Table 1.
The conformation of 2a in the solid state contains an
envelope cyclopentane ring in which C5 is out of the
plane containing the rest of cyclopentanic carbon atoms
and is close to the oxiranic oxygen atom, with the diphenyl-
phosphinoyl substituent in a pseudoaxial arrangement.
In the case of diphosphine dioxides 8a±d, assignment was
carried out by assuming that the preferred conformation of
these compounds in CDCl3 solution was similar to that
observed for 8b±d in the solid state, in which the cyclo-
pentane ring adopts an envelope conformation with the C2
atom out of the plane de®ned by the rest of cyclopentanic
carbon atoms with all of the substituents in pseudoequatorial
positions and an intramolecular hydrogen bond between the
hydroxyl group and the oxygen atom of the 2diphenyl-
phosphinoyl)methyl group through a seven-membered
ring, as shown in Fig. 3 for 8c. All of the single crystals
of compounds 8b±d correspond to their monohydrates, the
water molecules 2corresponding oxygen atom O4 for 8c,
shown in Fig. 3) establishing hydrogen bonds with the
3-phosphinoyl oxygen atoms.
1
Assignment of the H NMR spectra of compounds 2a±d
was carried out by assuming that all of them exist preferen-
tially in CDCl3 solution in a conformation similar to that
observed for 2a in the solid state. Similarly, assignment of
the 1H NMR spectra of compounds 5a±d was carried out by
assuming a similar conformation to that of 2a±d, except
for the diphenylphosphinoyl substituent which occupies a
pseudoequatorial position.
Worthy of note, the observed 3J213C±31P) coupling constant
values were of diagnostic interest to con®rm the assigned
conformations, since they follow a Karplus relationship.7,8
Thus, C3 and C4 in compounds 2a±d appear as singlets,
showing that their 3J213C±31P) coupling constants are close
to 0 Hz in accord with dihedral angles C3±C2±C1±P and
C4±C5±C1±P close to 908. The above dihedral angles for 2a
obtained from the single crystal X-ray diffraction structure
were 107.3 and 95.98, respectively.
3
As before, the observed J213C±31P) values were of diag-
nostic interest to con®rm the assigned conformations.
Signi®cant 3J213C±31P) values for compounds 8a±d
together with the corresponding dihedral angles obtained
from the single crystal X-ray diffraction structures of
8b±d are collected in Table 2. The results in Table 2
con®rm the preferred conformation of compounds 8a±d in
CDCl3 solution to be similar to those observed for
compounds 8b±d in the solid state.
In the cases of compounds 5a±d, if the assumed preferred
conformations with the phosphinoyl substituents in pseudo-
Although the conjugate addition to a,b-unsaturated carbo-
nyl compounds is a well established reaction, there is little
information in the literature regarding conjugate additions
to a,b-unsaturated phosphinoyl compounds.9 It is known
that amines,10,11 amides,11 organocuprates12 and silyl
cuprates13 add to the electrophilic double bond of achiral
vinyl phosphine oxides. Moreover, Warren et al.,14 have
recently described the diastereoselective conjugated
addition of hydrogen, carbon, silicon, sulfur, nitrogen and
oxygen nucleophiles to acyclic g-oxygenated chiral vinyl
phosphine oxides to give b-substituted phosphine oxides.
However, the diastereoselective nucleophilic addition of a
phosphinoylmethyl group to a cyclic vinyl phosphine oxide
to give a 1,3-diphosphine dioxide with stereocontrolled
formation of two new stereogenic centers, as in the
examples herein reported, has no precedent.
Preliminary studies carried out with enantioenriched 7a
244% ee)15 showed its reaction with the lithium derivative
of 9 to take place without racemization. This result opens
Figure 3. X-Ray diffraction structure 2ORTEP) of 8c.
Table 2. Signi®cant 3J213C±31P) values 2Hz) for compounds 8a±d and dihedral angles 28) 2from the single crystal X-ray diffraction structures) for compounds
8b±d
3J213C±31P) 2dihedral angle)
8
a
8
b
8
c
C1±C3±POR2 2C1±C2±C3±P)
C1±CH2PO2C6H5)2 2C1±C2±CH2±P)
C3±CH2PO2C6H5)2 2C3±C2±CH2±P)
C5±C3±POR2 2C5±C4±C3±P)
CH2±C3±POR2 2C5±C4±C3±P)
10.6
2.7
12.8
4.3
11.6 2162.6)
<0 267.1)
14.2 2177.0)
5.6 2152.3)
<0 274.4)
11.6 2158.0)
<0 274.3)
14.2 2168.4)
6.0 2134.6)
<0 278.1)
12.3 2157.8)
<0 264.3)
14.5 2179.9)
6.4 2132.0)
<0 278.9)
<0

3476
P. Camps et al. / Tetrahedron 58 42002) 3473±3484
the way for the preparation of enantiopure diphosphine
dioxides 8, from which the corresponding 1,3-diphosphines
could be obtained. This kind of diphosphines have rarely
been used as ligands for metal-catalyzed asymmetric
reactions.16
at room temperature for 18 h. The mixture was cooled 2ice-
bath), treated with saturated aqueous solution of NH4Cl
250 mL), made acidic 2pHˆ1) with 5N H2SO4 235 mL),
and concentrated in vacuo to give an oily residue, which
was stirred with hexane 2200 mL) for 2 h. The hexane
solution was discarded and the hexane insoluble material
was dissolved in H2O 2100 mL), the solution was made
strongly basic with 5N NaOH 2150 mL) and was concen-
trated in vacuo to give a residue which was extracted by
stirring with ethyl acetate 23£200 mL) for 2 h each time.
The organic extracts were dried 2Na2SO4), ®ltered and
evaporated under reduced pressure to give 3a as a pale
brown solid 27.24 g). Standard column chromatography
[silica gel 2150 g), ethyl acetate] gave pure 3a 23.82 g,
45% yield). The analytical sample of 3a was obtained as a
white solid by crystallization 2hexane/ethyl acetate 3:1), mp
125±1268C. IR 2KBr), nmax: 3054, 2939, 1436, 1180, 1118,
3. Experimental
3.1. General
Melting points were determined with a MFB 595010 M
Gallenkamp melting point apparatus. Unless otherwise
stated, NMR spectra were recorded in CDCl3 in the follow-
1
ing spectrometers: H NMR 2500 MHz, Varian VXR 500),
13C NMR 275.4 MHz, Varian Gemini 300), 31P NMR
1
2121.4 MHz, Varian Unity 300 Plus). H and 13C NMR
1
1071, 918, 750, 723, 701, 640 cm21; H NMR, dˆ7.79±
chemical shifts 2d) are reported in ppm related to internal
tetramethylsilane 2TMS) and 31P NMR chemical shifts 2d)
are reported in ppm relative to 85% H3PO4 as external
standard. The multiplicity of the signals is: s, singlet; d,
doublet; t, triplet; q, quartet; h, heptuplet. For the different
cyclopentanic compounds, the term Ha or Hb are assigned to
hydrogen atoms which are cis or trans, respectively, relative
to the substituent at position 1. In compounds 8a±d, the
terms Hsyn or Hanti refer to the protons of the CH2PO2C6H5)2
methylene group, which in the assumed preferred conforma-
tion are syn or anti, respectively, to the 2-H atom. IR spectra
were recorded on a FT/IR Perkin±Elmer spectrometer,
model 1600; only strong or medium intensity absorption
bands are given. Routine MSspectra were taken on a
Hewlett±Packard 5988A spectrometer, the sample was
introduced directly or through a gas chromatograph,
Hewlett±Packard model 5890 Series II, equipped with a
30-meter HP-5 25% diphenyl±95% dimethyl-polysiloxane)
column [conditions: 10 psi, initial temperature: 1008C
22 min), then heating at a rate of 108C/min till 2508C, then
isothermic] and the electron impact technique 270 eV).
Only signi®cant ions are given: those with higher relative
abundance, except for the ions with higher m/z values. Silica
gel SDS 60 270±200 mm) or 235±70 mm) was utilized for
the standard and ¯ash column chromatography, respec-
tively. NMR and routine MSspectra were performed at the
7.71 2complex signal, 4H, diastereotopic Ar-Hortho), 7.51±
7.47 2complex signal, 2H, diastereotopic Ar-Hpara), 7.46±
7.40 2complex signal, 4H, diastereotopic Ar-Hmeta), 5.91 2m,
1H, 3-H), 5.55±5.52 2m, 1H, 2-H), 3.71±3.64 2m, 1H, 1-H),
2.39±2.09 2complex signal, 4H, 4-Ha, 4-Hb, 5-Ha, 5-Hb);
13C NMR, dˆ135.7 2CH, d, 2JC±Pˆ11.6 Hz, C3), 132.7 2C,
1
1
d, JC±Pˆ95.2 Hz) and 131.8 2C, d, JC±Pˆ94.2 Hz) 2dia-
stereotopic Ar-Cipso), 131.4 2CH, broad s, Ar-CHpara),
2
2
131.2 2CH, d, JC±Pˆ8.6 Hz) and 131.0 2CH, d, JC±P
ˆ
ˆ
3
8.6 Hz) 2diastereotopic Ar-CHortho), 128.3 2CH, d, JC±P
11.1 Hz) and 128.2 2CH, d, 3JC±Pˆ11.2 Hz) 2diastereotopic
Ar-CHmeta), 125.3 2CH, d, 3JC±Pˆ6.0 Hz, C2), 46.1 2CH, d,
1JC±Pˆ72.4 Hz, C1), 32.6 2CH2, d, 3JC±Pˆ2.0 Hz, C4), 23.6
2CH2, s, C5); 31P NMR, dˆ32.8; MS2EI), m/z 2%): 268
2Mz1, 8), 202 [HPO2C6H5)2z1, 100], 201 [PO2C6H5)21, 43],
155 224), 77 2C6H51, 48), 67 2C5H71, 33). Anal. calcd for
C17H17OP: C, 76.11; H, 6.39. Found: C, 75.82; H, 6.48.
3.1.2. Dicyclohexyl-ꢀ2-cyclopentenyl)phosphine oxide ꢀ3b).
To a suspension of Mg turnings 29.72 g, 0.40 mol) and a
catalytic amount of I2 in anhydrous THF 2120 mL) at
2108C, was added dropwise 3-chlorocyclopentene
232.8 mL, 90% content, 0.28 mol) in anhydrous THF
2120 mL). The mixture was stirred at 2108C for 5 h and
the ®ltered suspension was added via cannula to a cold
solution 2ice-bath) of chlorodicyclohexylphosphine and
diethyl ether [ratio 1.1:1 21H NMR), 9.48 g, 31.6 mmol] in
anhydrous THF 2100 mL). When the addition was over, the
ice-bath was removed and the mixture was stirred at room
temperature for 18 h. The mixture was cooled 2ice-bath),
treated with saturated aqueous solution of NH4Cl 250 mL),
made acidic 2pHˆ1) with 2N H2SO4 228 mL), and concen-
trated in vacuo to give a yellow oily residue, which was
stirred with hot diethyl ether 2400 mL) for 2 h. The ethereal
solution was discarded and the ether insoluble residue was
dissolved in H2O 2150 mL), was made basic with 5N NaOH
240 mL) and was stirred with ethyl acetate 2400 mL) for
36 h. The organic layer was separated, dried 2Na2SO4),
®ltered and evaporated in vacuo to give impure 3b as a
dark viscous oil 25.12 g). The aqueous layer was stirred
with ethyl acetate 2400 mL) for 48 h, the organic phase
was separated, dried 2Na2SO4), ®ltered and evaporated to
give a further amount of impure 3b 21.71 g), that was
combined with the previous extract. Part of this product
2580 mg) was submitted to ¯ash column chromatography
Â
Á
Serveis Cientõ®co-Tecnics of the University of Barcelona,
while elemental analyses were carried out at the Micro-
Â
analysis Service of the Centro de Investigacion y Desarrollo
2C.I.D.), C.S.I.C., Barcelona, Spain. Chlorodiisopropyl-
phosphine and chlorodiphenyl-phosphine were purchased
from Aldrich Chemical Co. and chlorodicyclohexyl-
phosphine was purchased from Strem Chemical Inc. Chloro-
dicyclopentylphosphine was prepared according to the
method previously described.17
3.1.1. ꢀ2-Cyclopentenyl)diphenylphosphine oxide ꢀ3a).
To a suspension of Mg turnings 29.1 g, 0.37 mol) and a
catalytic amount of I2 in anhydrous THF 290 mL) at
2208C, was added dropwise 3-chlorocyclopentene 228.7
mL, 97% content, 0.29 mol) in anhydrous THF 290 mL).
The mixture was stirred at 2108C for 5 h and the ®ltered
suspension was added via cannula to a cold solution 2ice-
bath) of chlorodiphenylphosphine 25.70 mL, 7.00 g, 32
mmol) in anhydrous THF 260 mL). When the addition was
over, the ice-bath was removed and the mixture was stirred

P. Camps et al. / Tetrahedron 58 42002) 3473±3484
3477
[silica gel 253 g), ethyl acetate/methanol mixtures]. On
elution with a mixture of ethyl acetate/methanol in the
ratio of 99:1, pure 3b 2280 mg) was obtained as a pale
yellow oil 237% yield). The analytical sample of 3b was
obtained as a colorless oil by distillation 21008C/1.0 Torr).
IR 2KBr), nmax: 3147 2OH st, H2O) 2924, 2849, 1445, 1404,
3H) [diastereotopic CH2CH3)2]; 13C NMR, dˆ133.8 2CH,
3
2
d, JC±Pˆ10.2 Hz, C3), 127.2 2CH, d, JC±Pˆ4.7 Hz, C2),
1
3
42.7 2CH, d, JC±Pˆ60.9 Hz, C1), 32.5 2CH2, d, JC±P
ˆ
1
3.0 Hz, C4), 25.4 2CH, d, JC±Pˆ61.0 Hz) and 25.2 2CH,
1
d, JC±Pˆ61.3 Hz) [diastereotopic CH2CH3)2], 23.7 2CH2,
broad s, C5), 16.5±16.2 [CH3, overlapped d, diastereotopic
CH2CH3)2]; 31P NMR, dˆ56.4; MS2EI), m/z 2%): 200
2Mz1, 14), 158 [2M2C3H6)z1, 2] 157 [2M2C3H7)1, 2], 134
[2M2C5H6)z1, 88], 92 [2C3H7POH2)z1, 100], 91 212), 67
2C5H71, 34). Anal. calcd for C11H21OP´2/5H2O: C, 63.68;
H, 10.60. Found: C, 63.87; H, 10.36.
1
1212, 1158, 1116, 918, 891, 852, 726 cm21; H NMR, dˆ
5.99 2dq, Jˆ5.5, 2.5 Hz, 1H, 3-H), 5.74 2dq, Jˆ5.5, 2.5 Hz,
1H, 2-H), 3.23±3.15 2m, 1H, 1-H), 2.56±2.39 2complex
signal, 2H, 4-Ha and 4-Hb), 2.28±2.11 2complex signal,
2H, 5-Ha and 5-Hb), 2.00±1.79 2complex signal, 10H),
1.77±1.67 2complex signal, 2H), 1.51±1.37 2complex
signal, 4H) and 1.31±1.18 2complex signal, 6H) 2cyclohexyl
H); 13C NMR, dˆ133.7 2CH, d, 3JC±Pˆ10.0 Hz, C3), 127.1
3.1.4. ꢀ2-Cyclopentenyl)dicyclopentylphosphine oxide
ꢀ3d). To a suspension of Mg turnings 28.8 g, 0.36 mol)
and a catalytic amount of I2 in anhydrous THF 290 mL) at
2108C was added dropwise 3-chlorocyclopentene 232.0 g,
containing 7% of cyclopentadiene, 0.29 mol) in anhydrous
THF 290 mL). The mixture was stirred for 6 h at 2108C and
the ®ltered suspension was added via cannula to a cold 2ice-
bath) solution of the chlorodicyclopentylphosphine17
25.93 g, 29 mmol) in anhydrous THF 260 mL). When
the addition was over, the ice-bath was removed and the
mixture was stirred at room temperature for 18 h. The
mixture was cooled 2ice-bath), treated with saturated
aqueous solution of NH4Cl 248 mL), made acidic 2pHˆ1)
with 5N H2SO4 2150 mL) and concentrated in vacuo to give
a residue, which was stirred with hexane 2200 mL) for 2 h.
The hexanic solution was dried 2Na2SO4), ®ltered and
evaporated in vacuo to give impure 3d as a brown oil
22.27 g). The hexane insoluble material was dissolved in
H2O 2100 mL), made basic with 5N NaOH 2200 mL) and
extracted with ethyl acetate 23£200 mL). The combined
organic extracts were dried 2Na2SO4), ®ltered and evapo-
rated in vacuo to give a further amount of impure 3d 23.43 g,
80% approximate global yield). This compound could not
be fully puri®ed and was used as such in the next stage. 1H
NMR 2300 MHz) dˆ5.88 2m, 1H, 3-H), 5.76 2m, 1H, 2-H),
3.20 2m, 1H, 1-H), 2.46 2m, 2H, 4-Ha and 4-Hb), 2.2±1.5
2complex signal, 20H, cyclopentyl H, 5-Ha and 5-Hb); 13C
NMR, dˆ133.3 2CH, d, 3JC±Pˆ10.6 Hz, C3), 127.5 2CH, d,
2
1
2CH, d, JC±Pˆ5.1 Hz, C2), 42.7 2CH, d, JC±Pˆ61.3 Hz,
1
1
C1), 36.0 2CH, d, JC±Pˆ61.4 Hz) and 35.8 2CH, d, JC±P
ˆ
61.3 Hz) 2diastereotopic cyclohexyl CH), 32.5 2CH2, d,
3JC±Pˆ3.0 Hz, C4), 26.8±25.9 2CH2, complex signal, cyclo-
hexyl CH2), 23.7 2CH2, broad s, C5); 31P NMR, dˆ49.0; MS
2EI), m/z 2%): 280 2Mz1, 9), 214 [2M2C5H6)z1, 75], 213
[2M2C5H7)1, 19], 199 [2M1H2C6H10)1, 14], 133 290),
132 [2M2C5H6±C6H10)z1, 71), 83 2C6H111, 42), 81 240),
67 2C5H71, 82), 55 2C4H71, 100). Anal. calcd for
C17H29OP´1.1H2O: C, 68.01; H, 10.48. Found: C, 67.80;
H, 10.33.
3.1.3. ꢀ2-Cyclopentenyl)diisopropylphosphine oxide ꢀ3c).
To a suspension of Mg turnings 24.86 g, 0.20 mol) and a
catalytic amount of I2 in anhydrous THF 250 mL) at
2108C was added dropwise 3-chlorocyclopentene 217.6 g,
containing 10% of cyclopentadiene, 160 mmol) in anhy-
drous THF 250 mL). The mixture was stirred for 5 h at
2108C and the ®ltered suspension was added via cannula
to a cold 2ice-bath) solution of chlorodiisopropylphosphine
22.7 mL, 2.49 g, 96% content, 16.3 mmol) in anhydrous
THF 2100 mL). When the addition was over, the ice-bath
was removed and the mixture was stirred at room tempera-
ture for 18 h. The mixture was cooled 2ice-bath), treated
with saturated aqueous solution of NH4Cl 225 mL), made
acidic 2pHˆ1) with 2N H2SO4 210 mL) and concentrated in
vacuo to give a residue, which was stirred with hot diethyl
ether 2200 mL) for 2 h. The ethereal solution was discarded
and the ether insoluble residue was dissolved in H2O
2100 mL), was made basic with 5N NaOH 230 mL) and
was stirred for 1 h with ethyl acetate 2200 mL). The organic
layer was separated, dried 2Na2SO4), ®ltered and evaporated
in vacuo to give impure 3c as a dark oil [2.22 g, 78% relative
area by GLC/MS]. The aqueous layer was extracted with
ethyl acetate 22£100 mL) and the combined organic extracts
were dried 2Na2SO4), ®ltered and evaporated under reduced
pressure to give a further amount of impure 3c 20.56 g, 90%
relative area by GLC/MS, 68% approximate global yield).
The analytical sample of 3c was obtained as a colorless oil
by distillation 2908C/0.5 Torr). IR 2KBr), nmax: 3425 2OH st,
H2O), 3054, 2961, 2934, 2874, 1464, 1172, 1149, 1025, 986,
926, 884, 687 cm21; 1H NMR, dˆ5.90 2dq, Jˆ5.0, 2.5 Hz,
1H, 3-H), 5.74 2dq, Jˆ6.0, 2.5 Hz, 1H, 2-H), 3.25±3.17 2m,
1H, 1-H), 2.56±2.40 2complex signal, 2H, 4-Ha and 4-Hb),
2.30±2.14 2complex signal, 2H, 5-Ha and 5-Hb), 2.11 2dh,
Jˆ10.0, 7.0 Hz, 1H) and 2.08 2dh, Jˆ11.0, 7.0 Hz, 1H)
[diastereotopic CH2CH3)2], 1.90 2broad s, H2O), 1.24 2dd,
Jˆ7.5, 14.0 Hz, 3H), 1.22 2dd, Jˆ7.5, 14.5 Hz, 3H), 1.208
2dd, Jˆ7.5, 14.5 Hz, 3H) and 1.207 2dd, Jˆ7.5, 14.5 Hz,
1
2JC±Pˆ4.4 Hz, C2), 45.3 2CH, d, JC±Pˆ64.6 Hz, C1), 36.6
1
1
2CH, d, JC±Pˆ65.5 Hz) and 36.4 2CH, d, JC±Pˆ65.5 Hz)
3
2diastereotopic cyclopentyl CH), 32.5 2CH2, d, JC±P
3.2 Hz, C4), 27.1±25.8 2complex signal, CH2, cyclopentyl
CH2), 23.6 2CH2, s, C5).
ˆ
3.1.5. Epoxidation of 3a: cis- and trans-ꢀ2,3-epoxycyclo-
pentyl)diphenylphosphine oxide ꢀ5a and 2a). A solution
of 3a 21.16 g, 4.3 mmol) in CH2Cl2 240 mL) was added to a
cold 2ice-bath) solution of m-CPBA 22.6 g, 57% content,
8.6 mmol) in CH2Cl2 280 mL) and the mixture was stirred
at room temperature for 18 h. The mixture was washed with
10% aqueous solution of NaHSO3 23£20 mL), saturated
aqueous solution of NaHCO3 23£20 mL), water 210 mL)
and brine 210 mL). The organic phase was dried 2Na2SO4),
®ltered and evaporated under reduced pressure to give a pale
yellow foamy solid 21.15 g). Standard column chroma-
tography of the above solid [silica gel 260 g), ethyl acetate]
gave in order of elution: 2a 20.82 g, 67% yield) and 5a
20.13 g, 11% yield). The analytical sample of 2a was
obtained as a white solid by crystallization 2mixture of
ethyl acetate/hexane in the ratio of 5:7), mp 133±1348C.
IR 2KBr), nmax: 3435 2OH st, H2O), 3051, 2922, 1436,

3478
P. Camps et al. / Tetrahedron 58 42002) 3473±3484
1
1182, 1151, 1118, 926, 838, 723, 695 cm21; H NMR,
dˆ7.83±7.78 2m, 2H) and 7.76±7.72 2m, 2H) 2diastereo-
topic Ar-Hortho), 7.54±7.43 2complex signal, 6H, diastereo-
topic Ar-Hmeta and Ar-Hpara), 3.55 2d, Jˆ2.5 Hz, 1H, 3-H),
3.49 2dd, Jˆ2.5, 1.5 Hz, 1H, 2-H), 3.15 2ddd, Jˆ9.0, 6.0,
1.5 Hz, 1H, 1-H), 1.96 2dd, Jˆ13.7, 8.2 Hz, 1H, 4-Hb),
12 cyclohexyl H, 4-Ha, 4-Hb 22.06, dd, Jˆ8.0, 13.0 Hz),
5-Ha, and 5-Hb], 1.46±1.32 2complex signal, 4H) and
1.30±1.17 2complex signal, 6H) 2rest of cyclohexyl H);
2
13C NMR, dˆ59.1 2CH, broad s, C3), 57.8 2CH, d, JC±P
ˆ
3.9 Hz, C2), 36.9 2CH, d, 1JC±Pˆ61.5 Hz) and 36.3 2CH, d,
1JC±Pˆ62.6 Hz) 2diastereotopic cyclohexyl CH), 36.0 2CH,
d, 1JC±Pˆ56.3 Hz, C1), 27.3 2CH2, broad s, C4), 26.9±25.9
2complex signal, CH2, cyclohexyl CH2), 21.0 2CH2, d,
2JC±Pˆ4.1 Hz, C5); 31P NMR, dˆ51.0; MS2EI), m/z 2%):
296 2M1, 1), 267 22), 214 [2M2C6H10)´1, 16], 199 214), 186
216), 133 225), 132 [2M22C6H10)´1, 28], 83 2C5H7O1, 45),
55 2100). Anal. calcd. for C17H29O2P: C, 68.89; H, 9.87.
Found: C, 68.79; H, 9.99. The analytical sample of 5b
was obtained as a white solid by crystallization 2ethyl
acetate), m.p. 132±133.58C. IR 2KBr), nmax: 2930, 2846,
1.95±1.86 2m, 1H, 5-Ha), 1.82±1.75 2m, 1H, 4-Ha), 1.78±
1.65 2m, 1H, 5-Hb); 13C NMR, dˆ132.1 2C, d, JC±P
ˆ
1
1
98.8 Hz) and 132.0 2C, d, JC±Pˆ95.8 Hz) 2diastereotopic
4
Ar-Cipso), 131.9 2CH, d, JC±Pˆ2.5 Hz) and 131.8 2CH, d,
4JC±Pˆ2.5 Hz) 2diastereotopic Ar-CHpara), 130.8 2CH, d,
2JC±Pˆ9.2 Hz, Ar-CHortho), 128.74 2CH, d, JC±Pˆ11.0 Hz)
3
3
and 128.72 2CH, d, JC±Pˆ11.0 Hz) 2diastereotopic
2
Ar-CHmeta), 58.6 2CH, s, C3), 57.2 2CH, d, JC±Pˆ6.1 Hz,
1
C2), 39.2 2CH, d, JC±Pˆ68.9 Hz, C1), 27.0 2CH2, s, C4),
20.5 2CH2, d, JC±Pˆ4.3 Hz, C5); 31P NMR, dˆ32.4; MS
1447, 1215, 1158, 1116, 1003, 917, 893, 856 cm21; H
2
1
2EI), m/z 2%): 284 2Mz1, 1), 283 24), 228 233), 202
[[HPO2C6H5)2]z1, 100], 201 295), 155 242), 83 2C5H7O1,
20), 77 2C6H51, 100). Anal. calcd for C17H17O2P: C,
71.82; H, 6.03. Found: C, 71.87; H, 6.06. The analytical
sample of 5a was obtained as a white solid by crystallization
2mixture of ethyl acetate/hexane in the ratio of 2:1), mp
164±164.58C. IR 2KBr), nmax: 3428 2OH st, H2O), 3051,
NMR, dˆ3.64 2broad d, Jˆ2.0 Hz, 1H, 2-H), 3.53 2broad
d, Jˆ2.5 Hz, 1H, 3-H), 2.33 2dddd, Jˆ14.0, 11.0, 8.5,
1.0 Hz, 1H, 1-H), 2.13 2dd, Jˆ13.5, 7.5 Hz, 1H, 4-Ha),
2.04±1.65 2complex signal, 13H, 11 cyclohexyl H, 5-Ha
and 5-Hb 21.74, pseudo dt, Jˆ12.5, 8.0 Hz)], 1.65±1.42
2complex signal, 6H, 5 cyclohexyl H and 4-Hb 21.62,
dddd, Jˆ14.0, 9.5, 8.0, 1.0 Hz)], 1.32±1.18 2complex
signal, 6H, rest of cyclohexyl H); 13C NMR, dˆ57.0 2CH,
s, 3JC±Pˆ10.6 Hz, C3), 56.2 2CH, d, 2JC±Pˆ3.4 Hz, C2), 38.0
2909, 1436, 1185, 1117, 850, 752, 721, 699 cm21 1H
;
NMR, dˆ7.88 2m, 2H) and 7.78 2m, 2H) 2diastereotopic
Ar-Hortho), 7.56±7.43 2complex signal, 6H, diastereotopic
Ar-Hmeta and Ar-Hpara), 3.57 2broad d, Jˆ2.0 Hz, 1H,
2-H), 3.47 2broad d, Jˆ2.5 Hz, 1H, 3-H), 2.78 2dddd, Jˆ
12.0, 10.5, 8.0, 1.0 Hz, 1H, 1-H), 2.12 2dd, Jˆ13.5, 7.5 Hz,
1H, 4-Ha), 1.81 2pseudo dt, Jˆ12.5, 8.0 Hz, 1H, 5-Hb), 1.68
2m, 1H, 4-Hb), 1.64±1.54 2m, 1H, 5-Ha); 13C NMR, dˆ
1
1
2CH, d, JC±Pˆ61.0 Hz, C1), 35.9 2CH, d, JC±Pˆ62.8 Hz)
1
and 35.7 2CH, d, JC±Pˆ62.7 Hz) 2diastereotopic cyclo-
3
hexyl CH), 27.2 2CH2, d, JC±Pˆ9.0 Hz, C4), 26.8±25.4
[complex signal, CH2, cyclohexyl CH2], 20.4 2CH2, s,
C5); 31P NMR, dˆ51.9; MS2EI), m/z 2%): 296 2Mz1, 1),
214 [2M2C6H10)z1, 6], 148 214), 133 29), 132
[2M22C6H10)z1, 7], 83 2C6H111, 33), 67 2C5H71, 100).
Anal. calcd for C17H29O2P: C, 68.89; H, 9.87. Found: C,
68.63; H, 9.81.
4
4
131.9 2CH, d, JC±Pˆ2.5 Hz) and 131.8 2CH, d, JC±P
ˆ
1
3.1 Hz) 2diastereotopic Ar-CHpara), 132.3 2C, d, JC±P
ˆ
1
97.6 Hz) and 131.2 2C, d, JC±Pˆ97.6 Hz) 2diastereotopic
2
Ar-Cipso), 131.4 2CH, d, JC±Pˆ9.1 Hz) and 131.1 2CH, d,
2JC±Pˆ9.2 Hz) 2diastereotopic Ar-CHortho), 128.5 2CH, d,
3.1.7. Epoxidation of 3c: cis- and trans-ꢀ2,3-epoxycyclo-
pentyl)diisopropylphosphine oxide ꢀ5c and 2c). From 3c
2300 mg, 1.5 mmol) and m-CPBA 2540 mg, 57% content,
1.8 mmol) and following the procedure described for 3a, a
mixture of 2c and 5c 20.29 g) was obtained as a yellow oil.
Standard column chromatography [silica gel 230 g),
mixtures of ethyl acetate/methanol] of the above product
gave, in order of elution: 2c 2200 mg, 62% yield) and a
mixture of 2c and 5c 210 mg, 3% yield), on elution with a
mixture ethyl acetate/methanol in the ratio of 97.8:2.2, and
5c 250 mg, 15% yield), on elution with a mixture of ethyl
acetate/methanol in the ratio of 97.6:2.4. The analytical
sample of 2c as a colorless oil was obtained by distillation
2908C/0.5 Torr). IR 2KBr), nmax: 3423 2OH st, H2O), 2961,
2935, 2876, 1466, 1390, 1175, 1147, 1022, 928, 885, 838,
706 cm21; 1H NMR, dˆ3.61 2broad d, Jˆ2.5 Hz, 1H, 2-H),
3.55 2broad d, Jˆ2.5 Hz, 1H, 3-H), 2.61 2dt, Jˆ1.0, 9.5 Hz,
1H, 1-H), 2.20±2.08 2broad signal, H2O), 2.08 2dh, Jˆ12.5,
7.5 Hz, 1H) and 2.03 2dh, Jˆ10.5, 7.5 Hz, 1H) [diastereo-
topic CH2CH3)2], 2.01 2broad dd, Jˆ14.0, 9.5 Hz, 1H,
4-Hb), 1.90 2broad dt, Jˆ9.5, 13.5 Hz, 1H, 5-Ha), 1.83
2ddt, Jˆ14.0, 1.0, 9.0 Hz, 1H, 4-Ha), 1.73±1.62 2m, 1H,
5-Hb), 1.19 2dd, Jˆ15.0, 7.5 Hz, 3H), 1.18 2dd, Jˆ15.0,
7.5 Hz, 3H), 1.16 2dd, Jˆ15.0, 7.5 Hz, 3H), 1.15 2dd, Jˆ
15.0, 7.5 Hz, 3H) [diastereotopic CH2CH3)2]; 13C NMR,
3JC±Pˆ11.6 Hz, Ar-CHmeta), 56.3 2CH, d, JC±Pˆ6.7 Hz,
3
1
C3), 56.2 2CH, s, C2), 41.5 2CH, d, JC±Pˆ75.0 Hz, C1),
27.5 2CH2, d, JC±Pˆ9.7 Hz, C4), 20.0 2CH2, s, C5); 31P
3
NMR, dˆ33.6; MS2EI), m/z 2%): 285 22), 284 2Mz1, 1),
219 244), 203 228), 202 [[HPO2C6H5)2]z1, 100], 201 283),
155 225), 83 2C5H7O1, 10), 77 2C6H51, 35). Anal. calcd for
C17H17O2P´1/4H2O: C, 70.70; H, 6.11. Found: C, 71.00; H,
6.19.
3.1.6. Epoxidation of 3b: cis- and trans-dicyclohexylꢀ2,3-
epoxycyclopentyl)phosphine oxide ꢀ5b and 2b). From
impure 3b 23.2 g, 48% relative area by GLC/MS, approxi-
mately 5.5 mmol) and m-CPBA 27.8 g, 57% content, 25.7
mmol), following a similar procedure to that described for
3a, a mixture of 2b and 5b 22.62 g) was obtained. Flash
column chromatography [silica gel 275 g), ethyl acetate/
methanol mixtures] of the above mixture gave in order of
elution: pure 2b 21.21 g, 74% yield), on elution with a
mixture of ethyl acetate/methanol in the ratio of 99:1, a
mixture of 2b and 5b 260 mg, 3.7% yield) and pure 5b
20.26 g, 16% yield), on elution with a mixture of ethyl
acetate/methanol in the ratio of 97:3. The analytical sample
of 2b was obtained as a white solid by crystallization 2ethyl
acetate), mp 129±1398C. IR 2KBr), nmax: 2932, 2848, 1444,
2
1211, 1162, 1118, 925, 892, 833 cm21; H NMR, dˆ3.67
dˆ59.0 2CH, broad s, C3), 57.7 2CH, d, JC±Pˆ4.1 Hz,
1
1
2broad d, Jˆ2.0 Hz, 1H, 2-H), 3.60 2m, 1H, 3-H), 2.62 2dt,
Jˆ1.5, 9.5 Hz, 1H, 1-H), 2.10±1.64 2complex signal, 16H,
C2), 36.0 2CH, d, JC±Pˆ55.8 Hz, C1), 27.2 2CH2, s, C4),
1
1
26.0 2CH, d, JC±Pˆ61.8 Hz) and 25.5 2CH, d, JC±P
ˆ

P. Camps et al. / Tetrahedron 58 42002) 3473±3484
3479
2
62.8 Hz) [diastereotopic CH2CH3)2], 20.9 2CH2, d, JC±P
ˆ
2Mz1, 5), 227 221), 200 [2M2C5H8)z1, 13], 186 220), 185
[2M2C5H7O)1, 38], 145 230), 119 241), 118
[2C5H9)POH2z1, 37], 99 237), 83 2C5H7O1, 37), 69
2C5H91, 53), 67 2C5H71, 100). Anal. calcd for C15H25O2P:
C, 67.14; H, 9.39. Found: C, 67.04; H, 9.23. The analytical
sample of 5d was obtained by crystallization 2hexane) as a
white hygroscopic solid, that easily became a wax. IR
2KBr), nmax: 3408 2OH st, H2O), 2954, 2868, 1451, 1165,
1145, 934, 850 cm21; 1H NMR, dˆ3.66 2d, Jˆ2.5 Hz, 1H,
2-H), 3.50 2d, Jˆ2.2 Hz, 1H, 3-H), 2.31 2ddd, Jˆ14.5, 10.6,
8.3 Hz, 1H, 1-H), 2.11 2dd, Jˆ13.5, 8.0 Hz, 1H, 4-Ha),
2.22±2.14 2m, 1H) and 2.12±2.05 2m, 1H) 2diastereotopic
cyclopentyl CH), 2.05±1.78 2complex signal, 8H, dia-
stereotopic cyclopentyl 2-H and 5-H), 1.78±1.66 2complex
signal, 5H, 4 diastereotopic cyclopentyl 3-H and 4-H, and
5-Hb), 1.65±1.54 2complex signal, 5H, 4 diastereotopic
cyclopentyl 3-H and 4-H, and 4-Hb), 1.53±1.42 2m, 1H,
3.8 Hz, C5), 16.4±16.2 [complex signal, CH3, diastereo-
topic CH2CH3)2]; 31P NMR, dˆ56.1; MS2EI), m/z 2%):
217 [2M1H)1, 3], 215 [2M2H)1, 6], 175 28), 174
[2M2C3H6)z1, 7], 173 216), 146 [2M2C3H6±CO)z1, 36],
134 [2M2C5H6O)z1, 73], 92 2C3H7POH2z1, 100), 83
2C5H7O1, 29). Anal. calcd for C11H21O2P´1/2H2O: C,
58.65; H, 9.85. Found: C, 58.53; H, 9.83. The analytical
sample of 5c as a colorless viscous oil was obtained by
distillation 2908C/0.5 Torr). IR 2KBr), nmax: 3294 2OH st,
H2O), 2961, 2936, 2876, 1466, 1173, 1146, 1025, 885,
851, 695, 643 cm21
;
1H NMR, dˆ3.69 2broad d, Jˆ
2.0 Hz, 1H, 2-H), 3.57 2broad d, Jˆ2.5 Hz, 1H, 3-H), 2.37
2dddd, Jˆ14.0, 11.0, 8.0, 1.5 Hz, 1H, 1-H), 2.21 [dh, Jˆ
11.0, 7.0 Hz, 1H, diastereotopic CH2CH3)2], 2.16 2broad dd,
Jˆ13.0, 7.5 Hz, 1H, 4-Ha), 2.14 [dh, Jˆ9.5, 7.0 Hz, 1H,
diastereotopic CH2CH3)2], 2.03 2broad s, H2O), 1.79
2broad dt, Jˆ12.0, 8.0 Hz, 1H, 5-Hb), 1.67 2dddd, Jˆ14.0,
10.0, 8.5, 1.5 Hz, 1H, 4-Hb), 1.57 2dddt, Jˆ12.0, 10.0, 7.5,
11.0 Hz, 1H, 5-Ha), 1.30 2dd, Jˆ14.5, 7.0 Hz, 3H), 1.281
2dd, Jˆ14.5, 7.0 Hz, 3H), 1.280 2dd, Jˆ14.5, 7.0 Hz, 3H),
1.26 2dd, Jˆ14.5, 7.0 Hz, 3H) [diastereotopic CH2CH3)2];
3
5-Ha); 13C NMR, dˆ56.7 2CH, d, JC±Pˆ10.9 Hz, C3),
1
56.2 2CH, s, C2), 39.9 2CH, d, JC±Pˆ64.7 Hz, C1), 37.1
1
1
2CH, d, JC±Pˆ66.4 Hz) and 36.5 2CH, d, JC±Pˆ66.6 Hz)
3
2diastereotopic cyclopentyl CH), 27.3 2CH2, d, JC±P
ˆ
10.3 Hz, C4), 27.2 2CH2, broad signal) and 26.8 2CH2,
broad signal) 2diastereotopic cyclopentyl C2 and C5), 26.7
13C NMR, dˆ56.9 2CH, d, JC±Pˆ10.6 Hz, C3), 56.1 2CH,
3
2
1
3
3
d, JC±Pˆ3.3 Hz, C2), 37.9 2CH, d, JC±Pˆ60.8 Hz, C1),
2CH2, d, JC±Pˆ8.9 Hz), 26.5 2CH2, d, JC±Pˆ8.5 Hz), 26.0
3
1
3
3
27.2 2CH2, d, JC±Pˆ8.8 Hz, C4), 24.3 [CH, d, JC±P
ˆ
2CH2, d, JC±Pˆ9.3 Hz) and 25.9 2CH2, d, JC±Pˆ9.7 Hz)
2diastereotopic cyclopentyl C3 and C4), 20.3 2CH2, s, C5);
31P NMR, dˆ53.6; MS2EI), m/z 2%): 269 22), 268 2Mz1, 3),
186 28), 185 [2M2C5H7O)1, 9], 134 228), 69 2C5H91, 20),
67 2C5H71, 100). Anal. calcd for C15H25O2P´1/2H2O: C,
64.96; H, 9.45. Found: C, 65.02; H, 9.69.
62.8 Hz, diastereotopic CH2CH3)2], 20.3 2CH2, s, C5),
16.0±15.6 [complex signal, CH3, diastereotopic
CH2CH3)2]; 31P NMR, dˆ57.1; MS2EI), m/z 2%): 217
21), 216 2Mz1, 0.6), 174 [2M2C3H6)z1, 2], 173 22), 134
[2M2C5H6O)z1, 18], 92 2C3H7POH2z1, 26), 67 2C5H7
,
1
100). Anal. calcd for C11H21O2P´2/3H2O: C, 57.91; H,
9.87. Found: C, 58.02; H, 9.81.
3.1.9. 3-ꢀDiphenylphosphinoyl)-2-cyclopentenol ꢀ7a). To
a mixture of 2a and 5a 24.25 g, 15 mmol) in ethanol
2150 mL) was added a solution of KOH in ethanol
218.7 mL, 1.6 M, 30 mmol) and the mixture was stirred at
room temperature for 18 h. Then the solution was evapo-
rated at reduced pressure to give a residue which was
dissolved in H2O 275 mL). The solution was made acidic
2pHˆ1) with 5N HCl 210 mL) and was extracted with
CH2Cl2 23£60 mL). The combined organic extracts were
dried 2Na2SO4), ®ltered and concentrated in vacuo to give
7a 24.21 g, 99% yield) as a pale yellow foamy solid. The
analytical sample of 7a was obtained as a white solid by
crystallization 2ethyl acetate), mp 110±1118C. IR 2KBr),
3.1.8. Epoxidation of 3d: cis- and trans-dicyclopentyl-
ꢀ2,3-epoxycyclopentyl)phosphine oxide ꢀ5d and 2d).
From impure 3d 23.43 g, approximately 13.6 mmol) and
m-CPBA 24.94 g, 57% content, 16.3 mmol) and following
the procedure described for 3a, a mixture of 2d and 5d
22.76 g) was obtained as an oil. Standard column chroma-
tography [silica gel 2150 g), ethyl acetate/methanol mixtures]
of the above product gave in order of elution: 2d 21.58 g,
43% yield) and 5d 20.43 g, 12% yield) on elution with a
mixture of ethyl acetate/methanol in the ratio of 21:1. The
analytical sample of 2d was obtained as a white solid by
crystallization 2hexane), mp 130.5±131.58C. IR 2NaCl),
n
max: 3338, 1604, 1438, 1333, 1175, 1107, 1086, 1027,
756, 724, 701 cm21
n
max: 3358 2OH st, H2O), 2955, 2868, 1451, 1297, 1251,
;
1H NMR, dˆ7.69±7.62 2complex
1228, 1160, 1142, 1055, 929, 905, 837 cm21; H NMR,
dˆ3.76 2d, Jˆ2.0 Hz, 1H, 2-H), 3.62 2d, Jˆ1.0 Hz, 1H,
3-H), 2.72 2ddd, Jˆ12.7, 9.5, 1.7 Hz, 1H, 1-H), 2.12 2dd,
Jˆ13.5, 8.5 Hz, 1H, 4-Hb), 2.13±1.99 2complex signal, 2H,
cyclopentyl CH), 1.96±1.82 2complex signal, 10H, cyclo-
pentyl 2-H and 5-H, 4-Ha, and 5-Ha), 1.82±1.71 2complex
signal, 5H, 4 cyclopentyl 3-H and 4-H, and 5-Hb), 1.69±
1.56 2complex signal, 4H, rest of cyclopentyl 3-H and 4-H);
13C NMR, dˆ58.9 2CH, s, C3), 58.0 2CH, d, 3JC±Pˆ5.1 Hz,
signal, 4H, diastereotopic Ar-Hortho), 7.52±7.48 2complex
signal, 2H, diastereotopic Ar-Hpara), 7.44±7.40 2complex
signal, 4H, diastereotopic Ar-Hmeta), 6.34 2dq, Jˆ10.2,
2.0 Hz, 1H, 2-H), 4.97±4.93 2m, 1H, 1-H), 3.60±3.15
2broad signal, 1H, OH), 2.70±2.63 2m, 1H, 4-Hb), 2.48±
2.34 2complex signal, 2H, 4-Ha and 5-Hb), 1.84 2ddt,
Jˆ13.5, 8.5, 5.5 Hz, 1H, 5-Ha); 13C NMR, dˆ150.0 2CH,
1
2
1
d, JC±Pˆ9.6 Hz, C2), 138.9 2C, d, JC±Pˆ100.3 Hz, C3),
4
131.9 2CH, d, JC±Pˆ2.0 Hz, 2Ar-CHpara), 131.3 2CH, d,
C2), 38.8 2CH, d, 1JC±Pˆ58.9 Hz, C1), 37.0 2CH, d, 1JC±P
ˆ
2JC±Pˆ10.2 Hz, 4Ar-CHortho), 131.1 2C, d, JC±P
ˆ
1
1
66.4 Hz) and 36.6 2CH, d, JC±Pˆ66.4 Hz) 2diastereotopic
cyclopentyl CH), 27.15 2CH2), 27.05 22CH2) and 26.96
2CH2), 2diastereotopic cyclopentyl C2 and C5), 26.7 2CH2,
105.3 Hz) and 130.9 2C, d, 1JC±Pˆ104.8 Hz) 2diastereotopic
3
Ar-Cipso), 128.5 2CH, d, JC±Pˆ12.1 Hz) and 128.4 2CH, d,
3JC±Pˆ12.2 Hz) 2diastereotopic Ar-CHmeta), 77.3 2CH, d,
3
3
3
s, C4), 26.4 2CH2, d, JC±Pˆ9.3 Hz), 26.3 2CH2, d, JC±P
ˆ
3JC±Pˆ18.2 Hz, C1), 34.2 2CH2, d, JC±Pˆ8.1 Hz, C5),
3
2
9.8 Hz), 26.05 2CH2, d, JC±Pˆ9.1 Hz) and 26.02 2CH2, d,
3JC±Pˆ9.9 Hz) 2diastereotopic cyclopentyl C3 and C4), 20.8
2CH2, s, C5); 31P NMR, dˆ55.0; MS2EI), m/z 2%): 268
31.8 2CH2, d, JC±Pˆ10.6 Hz, C4); 31P NMR, dˆ24.5; MS
2EI), m/z 2%): 284 2Mz1, 33), 267 [2M2OH)1, 30], 256 238),
255 248), 202 245), 201 [PO2C6H5)21, 89], 183 243), 125

3480
P. Camps et al. / Tetrahedron 58 42002) 3473±3484
[HPO2C6H5)1, 22], 77 2C6H51, 100), 51 296). Anal. calcd for
C17H17O2P: C, 71.82; H, 6.03. Found: C, 71.78; H, 6.07.
and concentrated in vacuo to give 7c 271 mg). The aqueous
phase was evaporated in vacuo to dryness and the residue
was extracted with ethyl acetate 250 mL). The organic phase
was dried 2Na2SO4), ®ltered and concentrated in vacuo to
give more 7c 2249 mg, 98% global yield). The analytical
sample of 7c was obtained as a colorless oil, by standard
column chromatography [silica gel 225 g), ethyl acetate/
methanol mixtures]. IR 2KBr), nmax: 3281, 2964, 2935,
2874, 1465, 1326, 1263, 1172, 1146, 1095, 882, 695,
3.1.10. 3-ꢀDicyclohexylphosphinoyl)-2-cyclopentenol ꢀ7b).
2a) From 5b. To a solution of 5b 2300 mg, 1.01 mmol) in
ethanol 26 mL) was added a solution of KOH in ethanol
21.2 mL, 1.6 M, 1.92 mmol) and the mixture was stirred at
room temperature for 18 h. Then the solution was evapo-
rated at reduced pressure to give a residue which was
dissolved in H2O 215 mL). The solution was made acidic
2pHˆ1) with 2N HCl 22.2 mL) and was extracted with
CH2Cl2 23£50 mL). The combined organic phases were
dried 2Na2SO4), ®ltered and concentrated in vacuo to give
7b 2290 mg, 98% yield). The analytical sample of 7b was
obtained as a white solid by crystallization 2ethyl acetate),
mp 152.5±1548C. IR 2KBr), nmax: 3209, 2932, 2847, 1447,
659 cm21
;
1H NMR, dˆ6.64 2dq, Jˆ8.5, 2.0 Hz, 1H,
2-H), 4.94 2m, 1H, 1-H), 4.0±3.4 2broad s, 1H, OH),
2.64±2.56 2m, 1H, 4-Hb), 2.39±2.31 2complex signal, 2H,
4-Ha and 5-Hb), 2.09±1.97 2complex signal, 2H, diastereo-
topic CH2CH3)2], 1.87±1.78 2m, 1H, 5-Ha), 1.19 2dd,
Jˆ15.0, 7.0 Hz, 3H), 1.17 2dd, Jˆ14.5, 7.5 Hz, 3H), 1.10
2dd, Jˆ14.5, 7.0 Hz, 3H), 1.07 2dd, Jˆ15.0, 7.5 Hz, 3H)
[diastereotopic CH2CH3)2]; 13C NMR, dˆ150.5 2CH, d,
1
1151, 1097, 1066, 1029, 876, 854, 821, 755, 730 cm21; H
1
NMR, dˆ6.60 2dq, Jˆ8.5, 2.0 Hz, 1H, 2-H), 4.94 2m, 1H,
1-H), 3.6±3.1 2broad s, 1H, OH), 2.63±2.54 2m, 1H, 4-Hb),
2.39±2.31 2complex signal, 2H, 4-Ha and 5-Hb), 1.98±1.91
2complex signal, 2H, 5-Ha and cyclohexyl CH), 1.86±1.60
2complex signal, 11H) and 1.44±1.13 2complex signal, 10H)
2JC±Pˆ5.6 Hz, C2), 136.3 2C, d, JC±Pˆ81.4 Hz, C3), 76.8
3
3
2CH, d, JC±Pˆ15.4 Hz, C1), 34.2 2CH2, d, JC±Pˆ6.5 Hz,
C5), 33.2 2CH2, d, 2JC±Pˆ9.3 Hz, C4), 25.1 2CH, d, 1JC±P
ˆ
1
68.5 Hz) and 24.7 2CH, d, JC±Pˆ67.9 Hz) [diastereotopic
CH2CH3)2], 15.9 2CH3, broad s) and 14.9 2CH3, broad s)
[diastereotopic CH2CH3)2]; 31P NMR, dˆ50.5; MS2EI),
m/z 2%): 216 2Mz1, 44), 199 [2M2OH)1, 59], 174 294),
173 [2M2C3H7)1, 88], 156 [2M2C3H6±H2O)z1, 49], 131
[2M2C3H7±C3H6)1, 43], 114 [2C5H5POH2)z1, 29], 113
2rest of cyclohexyl H); 13C NMR, dˆ150.5 2CH, d, 2JC±P
ˆ
5.1 Hz, C2), 136.8 2C, d, 1JC±Pˆ81.1 Hz, C3), 76.9 2CH, d,
3JC±Pˆ15.0 Hz, C1), 35.1 2CH2, d, 1JC±Pˆ68.1 Hz,) and 34.8
1
2CH, d, JC±Pˆ68.4 Hz) 2diastereotopic cyclohexyl CH),
3
2
34.2 2CH2, d, JC±Pˆ6.5 Hz, C5), 33.1 2CH2, d, JC±P
ˆ
[2M2C3H7±C3H6±H2O)1, 65], 92 2C3H7POH2z1, 15), 83
1
9.5 Hz, C4), 26.6 2CH2, broad s), 26.41 2CH2, broad s),
26.38 2CH2, broad s), 26.2 2CH2, d, JC±Pˆ3.9 Hz), 25.9
22CH2, broad s), 25.5 22CH2, broad s), 24.65 2CH2, d,
JC±Pˆ3.4 Hz), 24.6 2CH2, d, JC±Pˆ3.4 Hz) 2cyclohexyl
CH2); 31P NMR, dˆ43.3; MS2EI), m/z 2%): 296 2M1, 1),
278 [2M2H2O)z1, 4], 252 [2M2C2H4O)z1, 16], 214
[2M2C6H10)z1, 17], 196 [2M2C6H10±H2O)z1, 28], 170
[2M2C6H10±C2H4O)z1, 94], 114 [2M22C6H10±H2O)z1,
18], 113 220), 83 2C6H111, 39), 67 2C5H71, 49), 55 2100).
Anal. calcd for C17H29O2P: C, 68.89; H, 9.87. Found: C,
68.78; H, 9.84.
2C5H7O1, 85), 67 2C5H7
,
100). Anal. calcd for
C11H21O2P´1.8H2O: C, 53.12; H, 9.98. Found: C, 52.97;
H, 9.68.
2b) From 5c. Starting from 5c 2340 mg, 1.57 mmol) and
following the above described procedure, 7c 2324 mg,
95% yield) was obtained.
3.1.12. 3-ꢀDicyclopentylphosphinoyl)-2-cyclopentenol ꢀ7d).
To a mixture of 2d and 5d 2100 mg, 0.37 mmol) in ethanol
25 mL) was added a solution of KOH in ethanol 20.46 mL,
1.6 M, 0.74 mmol) and the mixture was stirred at room
temperature for 18 h. The solution was evaporated at
reduced pressure to give a residue which was dissolved in
H2O 25 mL). The solution was made acidic 2pHˆ1) with 2N
HCl 22 mL) and was extracted with CH2Cl2 23£10 mL). The
combined organic phases were dried 2Na2SO4), ®ltered and
concentrated in vacuo to give 7d 276 mg, 76% yield) as a
yellowish oil. IR 2NaCl), nmax: 3294, 2955, 2887, 1450,
2b) From 2b. To a solution of n-buthyllithium 21 mL, 1.6 M
in hexanes, 1.6 mmol) in THF 21 mL) at 2788C, was added
dropwise a solution of 2b 2296 mg, 1.0 mmol) in anhydrous
THF 23 mL). After 3 h at room temperature the mixture was
heated under re¯ux for 15 h. The mixture was allowed to
cool to room temperature, saturated aqueous solution of
NH4Cl 24 mL) was added, and the THF was evaporated
under reduced pressure. The residue was diluted with
water 210 mL) and extracted with ethyl acetate 23£
20 mL). The combined organic phases were dried
2Na2SO4) and concentrated in vacuo to give a red oil
2330 mg). Standard column chromatography [silica gel
230 g), ethyl acetate/methanol mixtures] of the above
product gave 7b 280 mg, 27% yield) as a white solid.
1
1327, 1259, 1153, 1098, 1062, 1026, 907 cm21; H NMR,
dˆ6.63 2dq, Jˆ9.0, 2.0 Hz, 1H, 2-H), 4.90 2m, 1H, 1-H),
3.45 2broad s, 1H, OH), 2.61±2.53 2m, 1H, 4-Hb), 2.35±2.27
2complex signal, 2H, 4-Ha and 5-Hb), 2.10±1.97 2complex
signal, 2H, diastereotopic cyclopentyl CH), 1.88±1.49
2complex signal, 17H, cyclopentyl CH2 and 5-Ha); 13C
2
NMR, dˆ149.3 2CH, d, JC±Pˆ5.7 Hz, C2), 138.1 2C, d,
3
1JC±Pˆ85.4 Hz, C3), 76.8 2CH, d, JC±Pˆ15.3 Hz, C1),
1
1
3.1.11. 3-ꢀDiisopropylphosphinoyl)-2-cyclopentenol ꢀ7c).
2a) From 2c. To a solution of 2c 2324 mg, 1.5 mmol) in
ethanol 26 mL) was added a solution of KOH in ethanol
22 mL, 1.6 M, 3.2 mmol) and the mixture was stirred at
room temperature for 18 h. The solution was evaporated
at reduced pressure to give a residue which was dissolved
in H2O 215 mL). The solution was made acidic 2pHˆ1) with
2N HCl 23 mL) and was extracted with CH2Cl2 23£50 mL).
The combined organic phases were dried 2Na2SO4), ®ltered
36.9 2CH, d, JC±Pˆ71.7 Hz) and 36.5 2CH, d, JC±P
ˆ
71.8 Hz) 2diastereotopic cyclopentyl CH), 34.2 2CH2, d,
3JC±Pˆ6.7 Hz, C5), 32.6 2CH2, d, JC±Pˆ10.2 Hz, C4),
2
26.8±26.6 2CH2) and 26.2±26.0 2CH2) 2cyclopentyl CH2);
31P NMR, dˆ43.9; MS2EI), m/z 2%): 268 2M1, 1), 200
[2M2C5H8)z1, 11], 182 [2M2C5H8±H2O)z1, 13], 156 252),
83 2C5H7O1, 32), 69 2C5H91, 49), 67 2C5H71, 100). Anal.
calcd for C15H25O2P´H2O: C, 62.92; H, 9.50. Found: C,
62.86; H, 9.15.

P. Camps et al. / Tetrahedron 58 42002) 3473±3484
3481
3.1.13. c-3-ꢀDiphenylphosphinoyl)-t-2-[ꢀdiphenylphos-
phinoyl)methyl]-r-1-cyclopentanol ꢀ8a). 2a) From
cold solution 2ice-bath) of 9 2525 mg, 2.39 mmol) in anhy-
drous THF 27 mL) was added dropwise n-butyllithium
22.4 mL, 1.6 M in hexanes, 3.82 mmol). The suspension
was cooled to 2788C and a solution of anhydrous 2b
2706 mg, 2.39 mmol, azeotropic distillation of the water
content with toluene in a Dean±Stark equipment) in THF
23 mL) was added dropwise. After 3 h at room temperature
the mixture was heated under re¯ux for 15 h. Then, it was
allowed to cool to room temperature, saturated aqueous
solution of NH4Cl 210 mL) was added, and the mixture
was evaporated to dryness in vacuo. The residue was
taken in water 210 mL) and extracted with CH2Cl2
23£10 mL). The combined organic phases were dried
2Na2SO4) and concentrated in vacuo to give a yellow solid
21.18 g). Flash column chromatography [silica gel 260 g),
ethyl acetate/methanol mixtures] gave 8b as a white solid
2900 mg, 74% yield) on elution with a mixture of ethyl
acetate/methanol in the ratio of 97:3, and 7b 2100 mg,
14%), on elution with a mixture of ethyl acetate/methanol
in the ratio of 96:4. The analytical sample of 8b was
obtained as a white solid by crystallization 2ethyl acetate),
mp 163±164.58C; IR 2KBr), nmax: 3486, 3422, 3360, 3295,
a
mixture of 2a and 5a. To a cold solution 2ice-bath) of 9
2388 mg, 1.80 mmol) in anhydrous THF 27.5 mL) was
added dropwise n-butyllithium 21.76 mL, 1.6 M in hexanes,
2.82 mmol). The suspension was cooled to 2788C and a
solution of a mixture of anhydrous epoxides 2a and 5a
2500 mg, 1.76 mmol, azeotropic distillation of the water
content with toluene in a Dean±Stark equipment) in THF
215 mL) was added dropwise. After 3 h at room tempera-
ture, the mixture was heated under re¯ux for 15 h. The
mixture was allowed to cool to room temperature, saturated
aqueous solution of NH4Cl 215 mL) was added, and the
organic phase was separated and evaporated to dryness in
vacuo. The residue was taken in water 215 mL) and
extracted with CH2Cl2 23£15 mL). The combined organic
phases were dried 2Na2SO4) and concentrated in vacuo to
give 8a as a brown foamy solid 2770 mg, 87% yield). The
analytical sample of 8a was obtained as a white solid by
crystallization 2ethyl acetate), mp 189.5±1908C. IR 2KBr),
n
max: 3425, 3255, 1437, 1173, 1144, 1120, 1103, 765, 745,
722, 697 cm21; 1H NMR, dˆ7.86±7.81 2m, 2H, Ar-Hortho),
7.73±7.68 2m, 2H, Ar-Hortho), 7.64±7.37 2complex signal,
14H, 4Ar-Hpara, 6Ar-Hmeta, 4Ar-Hortho), 7.32±7.28 2m, 2H,
2Ar-Hmeta), 4.01 2dt, Jˆ8.0, 6.5 Hz, 1H, 1-H), 3.24 2ddd,
Jˆ14.5, 8.2, 2.7 Hz, 1H, CHsynPO2C6H5)2), 2.94±2.86
2ddt, Jˆ19.5, 6.5, 10.5 Hz, 1H, 3-H), 2.29±2.15 2complex
signal, 2H, 2-H and CHantiPO2C6H5)2), 2.02±1.90 2complex
signal, 2H, 4-Hb and 5-Hb), 1.83±1.73 2m, 1H, 4-Ha), 1.32±
1.24 2m, 1H, 5-Ha); 13C NMR, dˆ133.15 and 133.07
[higher d signals of 2 d, Ar-Cipso of CH2PO2C6H5)2],
131.8 2CH, broad s, 212 diastereotopic Ar-CHpara), 131.8
[CH, d, 2JC±Pˆ9.1 Hz, Ar-CHortho of CH2PO2C6H5)2], 131.3
2929, 2853, 1440, 1163, 1140, 1125, 750, 695 cm21
;
1H NMR, dˆ8.03±7.95 2m, 2H), 7.74±7.72 2m, 2H)
2Ar-Hortho), 7.50±7.38 2complex signal, 6H, 4Ar-Hmeta and
2Ar-Hpara), 6.42 2broad s, 1H, OH), 3.96 2pseudo q, Jˆ
7.5 Hz, 1H, 1-H), 3.74 2dd, Jˆ15.0, 7.0 Hz, 1H,
CHsynPO2C6H5)2], 2.34±2.16 2complex signal, 2H, 2-H
and 3-H), 2.10 2m, 1H, 5-Hb), 2.02 [pseudo dt, Jˆ11.0,
15.0 Hz, 1H, CHantiPO2C6H5)2], 1.94 2broad d, Jˆ12.5 Hz,
1H) and 1.86±1.57 2complex signal, 14H) 212 cyclohexyl H,
4-Ha, 4-Hb and 5-Ha), 1.43±0.98 2complex signal, 10H, rest
ˆ
4
of cyclohexyl H); 13C NMR, dˆ131.82 2CH, d, JC±P
2
2
4
2CH, d, JC±Pˆ9.8 Hz) and 131.1 2CH, d, JC±Pˆ9.1 Hz)
3.2 Hz) and 131.78 2CH, d, JC±Pˆ3.2 Hz) 2Ar-CHpara),
1
1
[212Ar±CHortho of 3-PO2C6H5)2], 130.5 [lower d signal
132.8 2C, d, JC±Pˆ98.0 Hz) and 130.9 2C, JC±Pˆ98.0 Hz)
2
of one d, Ar-Cipso of 3-PO2C6H5)2], 130.3 [CH, d, JC±P
2
ˆ
ˆ
ˆ
2Ar-Cipso), 131.6 2CH, d, JC±Pˆ9.7 Hz) and 130.4 2CH, d,
9.1 Hz, 2Ar-CHortho of CH2PO2C6H5)2], 130.0 2C, d, 1JC±P
97.0 Hz, Ar-Cipso of 3-PO2C6H5)2), 128.8 2CH, d, JC±P
2JC±Pˆ9.3 Hz) 2Ar-CHortho), 128.7 2CH, d, JC±Pˆ12.2 Hz)
3
3
and 128.6 2CH, d, 3JC±Pˆ11.8 Hz) 2Ar-CHmeta), 78.7 2CH, d,
3
12.2 Hz), 128.7 2CH, d, JC±Pˆ11.0 Hz), 128.6 2CH, d,
3JC±Pˆ11.6 Hz, C1), 45.3 2CH, pseudo t, 2JC±Pˆ3.2 Hz, C2),
3JC±Pˆ12.1 Hz) and 128.4 2CH, d, JC±Pˆ11.6 Hz)
39.5 2CH, dd, JC±Pˆ60.1 Hz, JC±Pˆ14.2 Hz, C3), 34.8
3
1
3
3
1
2Ar-CHmeta), 78.7 2CH, dd, JC±Pˆ10.6, 2.7 Hz, C1), 43.5
2CH2, d, JC±Pˆ68.8 Hz, CH2PO2C6H5)2], 35.5 2CH, d,
1
3
1
2CH, s, C2), 41.7 2CH, dd, JC±Pˆ72.0 Hz, JC±Pˆ12.8 Hz,
1JC±Pˆ62.8 Hz) and 34.6 2CH, d, JC±Pˆ61.9 Hz) 2dia-
1
3
C3), 35.0 2CH2, d, JC±Pˆ68.9 Hz, CH2P), 32.5 2CH2, d,
stereotopic cyclohexyl CH), 32.7 2CH2, d, JC±Pˆ6.0 Hz,
3JC±Pˆ4.3 Hz, C5), 23.3 2CH2, s, C4); 31P NMR, dˆ38.3
[CH2PO2C6H5)2], 35.8 [3-PO2C6H5)2]; MS2EI), m/z 2%): 501
[2M1H)1, 1], 299 [[M2PO2C6H5)2]1, 100], 202 223), 201
[PO2C6H5)21, 95], 77 2C6H51, 35). Anal. calcd for
C30H30O3P2´1/2H2O C, 70.72; H, 6.13. Found: C, 70.88; H, 6.36.
C5), 26.7±25.1 2several CH2, cyclohexyl CH2), 22.5 2CH2,
s, C4); 31P NMR, dˆ37.4 [PO2C6H5)2], 53.9 [PO2C6H11)2];
MS2EI), m/z 2%): 513 [2M1H)1, 1], 429 [2M2C6H11)1, 2],
347
[2M2C6H10±C6H11)1,
11],
311
28),
299
[2M2C12H22PO)1, 100], 281 [2M2C12H22PO±H2O)1, 9],
201 [PO2C6H5)21, 46]. Anal. calcd for C30H42O3P2: C,
70.29; H, 8.26. Found: C, 70.28; H, 8.31.
2b) From 7a. To a cold 2ice-bath) solution of 9 278 mg,
0.35 mmol) in anhydrous THF 22 mL) was added dropwise
n-butyllithium 20.35 mL, 1.6 M in hexanes, 0.56 mmol).
The mixture was cooled to 2788C and a solution of anhy-
drous 7a, obtained by dissolving 7a 2100 mg, 0.35 mmol) in
toluene 25 mL) followed by distillation of most of the
toluene 24 mL) at atmospheric pressure, was added drop-
wise. After 3 h at room temperature the mixture was heated
under re¯ux for 15 h. Following the workup described
before, 8a 2152 mg, 87% yield) was obtained as a brown
foamy solid.
2b) From 7b. To a cold 2ice-bath) solution of 9 278 mg,
0.35 mmol) in anhydrous THF 23 mL) was added dropwise
n-butyllithium 20.35 mL, 1.6 M in hexanes, 0.56 mmol).
The mixture was cooled to 2788C and a solution of anhy-
drous 7b, obtained by dissolving 7b 2104 mg, 0.35 mmol)
in toluene 25 mL) followed by distillation of most of the
toluene 24 mL) at atmospheric pressure, was added drop-
wise. After 3 h at room temperature the mixture was heated
under re¯ux for 15 h. Following the workup described
before, a mixture of 8b 2main component) and 7b 2minor
component) in an approximate ratio of 97:3 21H NMR), was
quantitatively obtained.
3.1.14. c-3-ꢀDicyclohexylphosphinoyl)-t-2-[ꢀdiphenylphos-
phinoyl)methyl]-r-1-cyclopentanol ꢀ8b). 2a) From 2b. To a

3482
P. Camps et al. / Tetrahedron 58 42002) 3473±3484
Table 3. Experimental data of the X-ray crystal-structure determination of compounds 2a, 8b±8d18
Compound
2a
8b
8c
8d
Molecular formula
Molecular mass
Crystal system
Space group
C34H34O4P2
568.55
Monoclinic
P21/n
C30H44O4P2
530.63
Monoclinic
P21/n
C24H36O4P2
450.47
Monoclinic
P21/a
C28H40O4P2
502.54
Monoclinic
P21/n
Cell parameters
Ê
[a]
[a]
[a]
[b]
A 2A)
Ê
14.22226)
14.19025)
14.72626)
96.2623)
295422)
4
25.42323)
9.71722)
26.38122)
117.6326)
5773214)
8
12.0822)
18.4022)
12.250210)
119.0429)
238025)
4
13.7110210)
9.5540210)
20.8330210)
96.0740210)
2713.724)
4
b 2A)
Ê
c 2A)
b 28)
V 2A )
Ê 3
Z
F2000)
1200
1.278
2288
1.220
968
1.257
1080
1.230
D2calcd) 2mg m23
)
Size of crystal 2mm)
Measured re¯ect.
Independent re¯ect.
Observed re¯ect.
0.1£0.1£0.2
0.1£0.1£0.2
0.1£0.1£0.2
0.1£0.1£0.2
8869
8527
17210
16786
4429
4209
12004
5898
3387
0.184
16686
0.187
3399
0.210
4040
0.191
m2Mo Ka)a 2mm21
)
R
Rw
Drmax 2e A
Drmim 2e A
Re®ned parameters
Max. shift/e.s.d.
0.037
0.065
0.683
20.199
473
0.00
0.037
0.078
0.572
20.336
651
0.00
0.056
0.149
0.589
20.566
274
0.00
0.030
0.080
0.271
20.165
443
0.00
Ê 23
Ê 23
b
)
)
c
[a] Determined by automatic centering of 25 re¯ections 212,u,218). [b] Determined by automatic centering of 9418 re¯ections 23,u,308).
Ê
a
m2Mo Ka) linear absorption coef®cient. Radiation Mo Ka 2lˆ0.71069 A).
b
Maximum peaks in ®nal difference synthesis.
Minimum peaks in ®nal difference synthesis.
c
3.1.15. c-3-ꢀDiisopropylphosphinoyl)-t-2-[ꢀdiphenylphos-
phinoyl)methyl]-r-1-cyclopentanol ꢀ8c). 2a) From 2c. To
a cold 2ice-bath) solution of 9 2220 mg, 1.0 mmol) in
anhydrous THF 23 mL) was added dropwise n-butyllithium
21.0 mL, 1.6 M in hexanes, 1.6 mmol). The suspension was
cooled to 2788C and a solution of 2c, obtained by dis-
solving 2c 2216 mg, 1.0 mmol) in toluene 25 mL) followed
by distillation of most of the solvent 24 mL) at atmospheric
pressure, was added dropwise. After 3 h at room tempera-
ture the mixture was heated under re¯ux for 15 h. Then, it
was allowed to cool to room temperature, saturated aqueous
solution of NH4Cl 24 mL) was added and the mixture was
evaporated to dryness in vacuo. The residue was taken in
water 210 mL) and extracted with CH2Cl2 23£10 mL). The
combined organic phases were dried 2Na2SO4) and concen-
trated in vacuo to give a brown oil 2340 mg). Flash column
chromatography [silica gel 219 g), ethyl acetate/methanol
mixtures] gave 8b as a white solid 2290 mg, 67% yield)
on elution with a mixture ethyl acetate/methanol in the
ratio of 96:4. The analytical sample was obtained as a
white solid by crystallization 2ethyl acetate), mp 126±
1288C; IR 2KBr), nmax: 3410, 3218, 2962, 2878, 1466,
1JC±Pˆ101.0 Hz) and 130.1 2C, signal of overlapped d)
2Ar-Cipso), 131.7 2CH, broad s) 2Ar-CHpara), 131.4 2CH, d,
2JC±Pˆ9.8 Hz) and 130.3 2CH, d, 2JC±Pˆ9.8 Hz)
3
2Ar-CHortho), 128.68 2CH, d, JC±Pˆ11.7 Hz) and 128.55
3
3
2CH, d, JC±Pˆ11.1 Hz) 2Ar-CHmeta), 78.6 2CH, d, JC±P
ˆ
ˆ
ˆ
1
11.6 Hz, C1), 45.2 2CH, s, C2), 39.3 2CH, dd, JC±P
3
1
59.9 Hz, JC±Pˆ14.2 Hz, C3), 34.8 2CH2, d, JC±P
3
68.7 Hz, CH2PO2C6H5)2), 32.8 2CH2, d, JC±Pˆ5.6 Hz,
1
C5), 25.3 2CH2, d, JC±Pˆ62.6 Hz) and 23.8 2CH, d,
1JC±Pˆ62.0 Hz) [diastereotopic CH2CH3)2], 22.9 2CH2,
2
broad s, C4), 16.8 2CH3, d, JC±Pˆ3.3 Hz), 16.6 2CH3,
broad s), 15.9 2CH3, broad s), 15.4 2CH3, broad s) dia-
stereotopic CH2CH3)2]; 31P NMR, dˆ33.1 [PO2C6H5)2],
55.1 [PO2i-Pr)2]; MS2EI), m/z 2%): 433 21), 432 2Mz1,
0.5), 347 22M2C3H6±C3H7)1, 6], 299 [2M2C6H14PO)1,
100], 231 [2M2PO2C6H5)2)1, 11], 201 [PO2C6H5)21, 36].
Anal. calcd for C24H34O3P2´H2O: C, 63.98; H, 8.06. Found:
C, 64.25; H 7.82.
2b) From 5c. Starting from 9 2190 mg, 0.85 mmol), n-butyl-
lithium 20.85 mL, 1.6 M in hexanes, 1.36 mmol) and 5c
2183 mg, 0.85 mmol) and following the above described
procedure under 2a), 8c 2340 mg, 92% yield) was obtained.
1
1438, 1170, 1154, 1123, 1098, 793, 759, 745 cm21; H
NMR, dˆ8.05±8.00 2m, 2H) and 7.75±7.70 2m, 2H)
2Ar-Hortho), 7.50±7.44 2complex signal, 4H) and 7.42±
7.38 2m, 2H) 2Ar-Hmeta and Ar-Hpara), 6.8±6.0 2broad s,
1H, OH), 3.98 2pseudo q, Jˆ8.0 Hz, 1H, 1-H), 3.74 2ddd,
Jˆ15.0, 7.0, 2.0 Hz, 1H, CHsynPO2C6H5)2), 2.27 2m, 1H,
2-H), 2.21 2ddt, Jˆ13.5, 8.0, 11.0 Hz, 1H, 3-H), 2.11 2m,
1H, 5-Hb), 2.08±1.95 2complex signal, 3H, diastereotopic
CH2CH3)2 and CHantiPO2C6H5)2), 1.87±1.75 2m, 1H, 4-Hb),
1.75±1.60 2complex signal, 2H, 4-Ha and 5-Ha), 1.19 2dd,
Jˆ14.0, 7.0 Hz, 3H), 1.10 2dd, Jˆ14.5, 7.0 Hz, 3H), 1.09
2dd, Jˆ15.0, 7.5 Hz, 3H), 1.06 2dd, Jˆ15.0, 7.5 Hz, 3H)
[diastereotopic CH2CH3)2]; 13C NMR, dˆ132.9 2C, d,
2c) From 7c. Starting from 9 2166 mg, 0.75 mmol), n-butyl-
lithium 20.75 mL, 1.6 M in hexanes, 1.2 mmol) and 7c
2162 mg, 0.75 mmol) and following the above described
procedure under 2a), 8c 2180 mg, 56% yield) was obtained.
3.1.16. c-3-ꢀDicyclopentylphosphinoyl)-t-2-[ꢀdiphenyl-
phosphinoyl)methyl]-r-1-cyclopentanol ꢀ8d). 2a) From a
mixture of 2d and 5d. To a cold 2ice-bath) solution of 9
2403 mg, 1.86 mmol) in anhydrous THF 25 mL) was
added dropwise n-butyllithium 21.86 mL, 1.6 M in hexanes,
2.98 mmol). The suspension was cooled to 2788C and a

P. Camps et al. / Tetrahedron 58 42002) 3473±3484
3483
solution of a mixture of anhydrous 2d and 5d 2500 mg,
1.86 mmol, azeotropic distillation of the water content
with toluene in a Dean±Stark equipment) in THF 215 mL)
was added dropwise. After 3 h at room temperature the
mixture was heated under re¯ux for 15 h. The mixture
was allowed to cool to room temperature, saturated aqueous
solution of NH4Cl 28 mL) was added, and the organic phase
was separated and evaporated to dryness in vacuo. The resi-
due was taken in water 28 mL) and extracted with CH2Cl2
23£20 mL). The combined organic phases were dried
2anhydrous Na2SO4) and concentrated in vacuo to give 8d
as a brown foamy solid 2854 mg, 95%). The analytical
sample of 8d was obtained as a pale yellow solid by crystal-
lization 2AcOEt/hexane in the ratio of 10:1), mp 179±
1808C. IR 2KBr), nmax: 3430, 3308, 2955, 2865, 1436,
and intensity control; signi®cant intensity decay was not
observed. Lorentz polarization but no absorption correc-
tions were made. The structure was solved by Direct
methods, using SHELXS computer program19 and re®ned
by full-matrix least-squares method with SHELX9320 2for
8b and 8c) or SHELX9721 2for 2a and 8d) computer
P
programs. The function minimized was w[uFou22uFcu2]2,
where
wˆ[s22I)120.0269P)2]21
for
2a,
wˆ
[s22I)120.0365P)2]21 for 8b, wˆ[s22I)120.0926P)2]21 for
8c and wˆ[s22I)120.0551P)2]21 for 8d, being Pˆ
2uFou222uFcu2)/3 in all cases; f, f0 and f00 were taken from
International Tables of X-ray Crystallography.22 The
position of the hydrogen atoms for 8b±8d were computed
and re®ned with an overall isotropic temperature factor,
using a riding model. For 2a, 28 hydrogen atoms were
located from a difference synthesis and re®ned with an over-
all isotropic temperature factor and six hydrogen atoms
were computed and re®ned with an overall isotropic
temperature factor equals to 1.2 time the equivalent iso-
tropic temperature factor of the atom to which are linked
and using a riding model.
1172, 1149, 1121, 1104, 804, 758, 722, 697 cm21 1H
;
NMR, dˆ8.00±7.95 2m, 2H) and 7.75±7.70 2m, 2H)
2Ar-Hortho), 7.48±7.43 2complex signal, 4H) and 7.41±
7.37 2m, 2H) 2Ar-Hmeta and Ar-Hpara), 6.40 2broad s, 1H,
OH), 3.97 2pseudo q, Jˆ7.5 Hz, 1H, 1-H), 3.78 2ddd,
Jˆ15.0, 6.0, 1.0 Hz, 1H, CHsynPO2C6H5)2), 2.28±2.03
2complex signal, 4H, 2-H, 3-H, 5-Hb, CHantiPO2C6H5)2],
1.96±1.30 2complex signal, 21H, cyclopentyl H, 4-Ha,
ˆ
1
4-Hb and 5-Ha); 13C NMR, dˆ132.8 2C, d, JC±P
Acknowledgements
1
101.3 Hz) and 130.7 2C, d, JC±Pˆ98.5 Hz) 2diastereotopic
Â
Ar-Cipso), 131.8 2CH, broad s) and 131.7 2CH, broad s)
Financial support from the Direccion General de Investi-
2
2diastereotopic Ar-CHpara), 131.6 2CH, d, JC±Pˆ10.0 Hz)
Â
Â
gacion of Ministerio de Ciencia y Tecnologõa 2project
QUI1999-0512) and a fellowship from the Generalitat de
Catalunya 2to G. C.) are gratefully acknowledged. We
2
and 130.4 2CH, d, JC±3Pˆ9.1 Hz) 2diastereotopic
Ar-CHortho), 128.6 2CH, d, JC±Pˆ12.1 Hz, Ar-CHmeta),
3
78.7 2CH, d, JC±Pˆ12.3 Hz, C1), 44.9 2CH, s, C2), 41.6
Â
thank the Serveis Cientõ®co-Tecnics of the University of
Barcelona and particularly Dr M. Feliz and Dr A. Linares
Á
1
3
2CH, dd, JC±Pˆ63.7 Hz, JC±Pˆ14.5 Hz, C3), 36.8 2CH,
1
1
Á
for recording the NMR spectra, and Ms P. Domenech
from the Centro de Investigacion y Desarrollo 2C.I.D.)
d, JC±Pˆ66.1 Hz) and 35.1 2CH, d, JC±Pˆ65.9 Hz)
1
2diastereotopic cyclopentyl CH), 34.7 2CH2, d, JC±P
ˆ
Â
3
68.9 Hz, CH2PO2C6H5)2), 32.5 2CH2, d, JC±Pˆ6.4 Hz,
C5), 27.7 2CH2, s), 27.0 22CH2, s) and 25.9 2CH2, s) 2dia-
stereotopic cyclopentyl C2 and C5), 26.6 2CH2, d,
3JC±Pˆ8.9 Hz), 25.8±25.9 22CH2, d) and 25.7 2CH2, d,
3JC±Pˆ9.9 Hz) 2diastereotopic cyclopentyl C3 and C4),
22.6 2CH2, s, C4); 31P NMR, dˆ36.8 [PO2C6H5)2], 55.4
[2PO2C5H9)2]; MS2EI), m/z 2%): 485 [2M1H)1, 2], 299
[M2PO2C5H9)21, 100], 283 [M2[PO2C6H5)2]1, 14], 201
[PO2C6H5)21, 39], 69 2C5H91, 13), 67 2C5H71, 15). Anal.
calcd for C28H38O3P2: C, 69.41; H, 7.90. Found: C, 69.48; H,
7.95.
2Barcelona, Spain) for carrying out the elemental analyses.
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Á
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Â
Â
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