Stereoselective synthesis of spiro tricyclic polyoxygenated compounds: Solvolytic behavior of 1-(Tosyloxymethyl)spiro[2.4]hepta-4,6-diene

Article abstract of DOI:10.1055/s-0030-1258401

The Diels-Alder reaction of spirobicyclic cyclopentadiene derivatives, prepared by reaction of cyclopentadienyllithium and epichlorohydrin, with maleic anhydride gave a simple access to spiro tricyclic polyoxygenated compounds of synthetic interest. The s

Full text of DOI:10.1055/s-0030-1258401

674
PAPER
Stereoselective Synthesis of Spiro Tricyclic Polyoxygenated Compounds:
Solvolytic Behavior of 1-(Tosyloxymethyl)spiro[2.4]hepta-4,6-diene
Stereoselective
S
é
l
Spiro T
i
r
icycli
n
c
P
olyoxyge
e
nated
C
ompoundsReynaud,a Michel Giorgi,b Henri Doucet,*c Maurice Santelli*a
a
Laboratoire Chimie Provence, associé au CNRS, UMR 6264, Faculté des Sciences de Saint Jérôme,
Avenue Escadrille Normandie-Niemen, 13397 Marseille Cedex 20, France
Fax +33(4)91288758; E-mail: m.santelli@univ-cezanne.fr
b
c
Spectropôle, Faculté des Sciences de St-Jérôme, Avenue Escadrille Normandie-Niemen, 13397 Marseille Cedex 20, France
Institut Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes ‘Catalyse et Organometalliques’,
Campus de Beaulieu, 35042 Rennes, France
Fax +33(2)23236939; E-mail: henri.doucet@univ-rennes1.fr
Received 7 October 2010; revised 6 December 2010
The Diels–Alder reaction of the tosylate 1b3m,n with male-
ic anhydride led mainly to the endo-anti-isomer 3b (anti/
syn-isomers: 3b/2b, 2.35:1). The stereochemistry was
confirmed by an X-ray crystal structure determination of
Abstract: The Diels–Alder reaction of spirobicyclic cyclopentadi-
ene derivatives, prepared by reaction of cyclopentadienyllithium
and epichlorohydrin, with maleic anhydride gave a simple access to
spiro tricyclic polyoxygenated compounds of synthetic interest. The
solvolytic behavior of 1-(tosyloxymethyl)spiro[2.4]hepta-4,6-di- 3b (Figure 1).
ene, a 5-spirocyclopentadiene, shows that the ionization of the tosy-
late was unlikely.
a)
Key words: tricyclic compounds, Diels–Alder reaction, spiro com-
pounds, stereoselective synthesis
OH
OTs
1. n-BuLi
TsCl
O
2.
Cl
1a, 56%
1b, 95%
Diels–Alder reaction of cyclopentadienes with maleic an-
hydride allows the formation of building blocks useful for
the preparation of polypodal diphenylphosphino ligands,1
and particularly polypodal ligands with a side chain. We
have previously reported the Diels–Alder reaction of ful-
venes with maleic anhydride.2
1. NaH, THF
2. Br
OTBDMS
O
OTBDMS
Now, we report on the Diels–Alder reaction between the
spirobicyclic cyclopentadienes 1a–c, prepared from cy-
clopentadienyllithium and epichlorohydrin,3 and maleic
anhydride. The Diels–Alder adducts 2 and 3 could poten-
tially be employed as building blocks for the preparation
of supported ligands. Only the endo-adducts were ob-
tained as a mixture 1.33:1 of anti- and syn-isomers 3a and
2a, respectively (Scheme 1). A previous addition of 1a (or
related compounds with a protected hydroxy group) to 2-
chloroacrylonitrile afforded only the corresponding anti-
isomer3b (the stereochemistry of the cycloaddition with
alkyl acrylates,3f,n methyl vinyl ketone,3f acrylonitrile,3n
dimethyl azodicarboxylate,3c or dialkyl fumarate,3n ap-
pears not to have been determined), while N-phenylmale-
imide gave a 1:1 mixture of the two endo-adducts.3k The
postulated stereochemistry syn or anti results from com-
parison of the NMR spectra, which led us to assign the
higher field position of the methylene signal of the cyclo-
propane to the syn-isomer, which is attributable to shield-
ing by the endocyclic double bond (Scheme 2); more
subtle analysis of the NMR results confirmed this.4
1c, 55%
OR
b)
RO
O
O
+
O
O
+
O
1a–c
O
O
O
O
endo-syn
endo-anti
2a, 29%
2b, 22%
2c, 34%
3a, 39%
3b, 52%
3c, 28%
R = H:
R = OTs:
R = -(CH2)5-OTBDMS:
Scheme 1 (a) Synthesis of spiro[2.4]hepta-4,6-diene-1-methanol
(1a) and derivatives; (b) Diels–Alder reaction of 1a–c with maleic an-
hydride
This stereoselectivity results mainly from kinetic parame-
ters, and the anti p facial selectivity could be attributed to
steric hindrance. Indeed, calculations at the B3LYP/6-
31++G(d,p) level of the theory5 (without zero-point ener-
gy correction) show that 3b is the most stable isomer by
0.85 kcal/mol, which should lead to better selectivity (2b,
E = –1581.636 057 hartree; 3b, E = –1581.637 417 har-
tree).
SYNTHESIS 2011, No. 4, pp 0674–0680
x
x
.
x
x
.2
0
1
1
We have increased the steric shielding of one face of the
Advanced online publication: 12.01.2011
DOI: 10.1055/s-0030-1258401; Art ID: T20510SS
© Georg Thieme Verlag Stuttgart · New York
cyclopentadiene by the etherification of 1a with 1-bromo-

PAPER
Stereoselective Synthesis of Spiro Tricyclic Polyoxygenated Compounds
675
5-(tert-butyldimethylsiloxy)pentane6 to give the ether 1c. level of the theory5 (without zero-point energy correction)
In this case, the Diels–Alder reaction with maleic anhy- show that 1b is more stable than tosylate X by 10.6 kcal/
dride gave the syn-isomer 2c with a narrow majority (syn/ mol (1b, E = –1205.202 115 hartree; X, E = –1205.185
anti-isomers: 2c/3c 1.21:1).
190 hartree). From X, a Wagner–Meerwein transposition
gave the bicyclo[3.3.0]octa-1,3-dien-7-yl carbocation A,
precursor of 4.
The p facial selectivity in Diels–Alder reactions has been
correlated with hyperconjugative stabilization involving
the donation of electron density from the substituent.7 In Treatment of 1b with lithium bromide in tetrahydrofuran
the case of 1a–c, among the substituents, the best donor gave rise to the cyclopropylmethyl bromide 53e in good
group, favoring the syn-isomer, is the ether of 1c with a yields; treatment with sodium carbonate in dimethyl
contrasteric addition to the most nucleophilic diene face.7c sulfoxide led to the unstable aldehyde 63d,e,g,h according to
the Kornblum reaction.11
13C NMR
10.0 0.7 ppm
13C NMR
12.3 0.6 ppm
OR1
R1O
a)
OH
Br
LiBr
Li2CO3
R2
R2
+
1b
1a, 34%
H2O–THF
reflux
THF, 25 °C
3 d
R2
R2
syn-isomer
6 compounds
anti-isomer
5, 95%
4, 44%
NaHCO3
Scheme 2 Stereochemistry of adducts according to the 13C NMR
spectra
DMSO
80 °C
O
H
6, 20% (unstable)
b)
OH
OTs
(+)
OTs
4
X
A
1b
Scheme 3 Reactivity of the tosylate 1b
Figure 1 ORTEP diagram of tosylate 3b
Scheme 4 Spontaneous isomerizations of spirocyclopentadienes
The reactivity of the tosylate 1b has not been previously
investigated although it is an interesting example of a cy-
clopropylcarbinyl system with the possibility of the for-
mation of nonclassical ions with a resonance between the
structures B, C, and D (Scheme 4).8 Moreover, com-
pounds 4–6 might be used for the preparation of supported
ligands.2 In fact, very clean substitution reactions oc-
curred [Scheme 3 (a)]. Hydrolysis of 1b afforded the pre-
cursor alcohol 1a and bicyclo[3.3.0]octa-5,8-dien-3-ol
(4). The reduced number of signals in the NMR spectra
confirmed the symmetry of the alcohol 4. A facile and re-
versible 1,5-alkyl shift converts the spiro-tosylate 1b into
the cyclobutyl tosylate X [Scheme 3 (b)]. Oda and
Breslow have already reported that bicyclo[3.2.0]hepta-
1,3-diene undergoes a fast isomerization to give
spiro[2.4]hepta-4,6-diene.9 On the other hand, cyclobu-
tano[a]indene was spontaneously formed by the rear-
The structure of the nonclassical ion B arising from the
hypothetical release of the tosylate anion of 1b has been
calculated at the B3LYP/6-311++G(3df,2pd) level of the
theory (E = –310.004 752 hartree, without zero-point en-
ergy correction) (Scheme 5). Among the three mesomeric
structures B, C, and D, the most similar structure to E,
which was obtained by calculation, corresponds to D, as
demonstrated by the length 2.0 Å of the C1–C7 bond of
the cyclopropane. But this structure fits to a cyclopentadi-
enyl cation with an ‘antiaromatic’ character.12 Indeed, the
calculated structure shows that the conjugation in the cy-
clopentadiene moiety is reduced, as given by the length of
the C3–C4 bond (1.503 Å instead of 1.474 Å in the calcu-
lated structure of cyclopentadiene at the same level of the-
ory). The relative sizes of component atomic orbitals of
the LUMO (29th MO), show that this MO was mainly lo-
calized on C1 and C8 (Figure 2). The spiro carbocation C
rangement
of
spiro[cyclopropane-1,2¢-indene]
(Scheme 4).10 Calculations at the B3LYP/6-311++G(d,p)
Synthesis 2011, No. 4, 674–680 © Thieme Stuttgart · New York

676
C. Reynaud et al.
PAPER
(E = –309.980 542 hartree) is less stable than E by 15.2
kcal/mol (at the same level of theory). The isomeric bicy-
clic cation A [Scheme 3 (b)] (E = –310.000 155 hartree) is
more stable than E by 12.3 kcal/mol, confirming the in-
stability of the former. In conclusion, this theoretical
study shows that the ionization of the tosylate 1b was im-
probable and explained that mainly direct substitution re-
actions occurred. In particular, all attempts to open the
cyclopropane of alcohol 1a by heating in the presence of
trifluoroacetic acid failed.
OH
O
OR
LiAlH4
THF
+
2a,c
OH
OH
OH
OH
2a:
2c:
7a, 78%
R = TBDMS, 7c, 20% R = H, 9, 40%
RO
LiAlH4
THF
3a,c
(+)
(+)
OH
OH
OTs
?
(+)
3a, R = H:
8a, 78%
3c, R = (CH2)5OTBDMS: 8c, 62%
1b
B
C
D
OH
O
1.345
H
H
8
OMe
H
H 1.998
H
1.459
H
7a
H
H
7
H(+)
5
1
4
1.539
1.344
H
O
H
6
H
1.503
H
H
H
3
10a, 72%
2
H
H
1.449
1.337
RO
H
H
1.483
Mulliken charges: C1, 0.434; C2, 0.043;
C3, –0.245; C4, –0.149; C5, 0.053;
C6, 0.317; C7, 0.249; C8, –0.267.
bond lengths (Å)
OMe
H(+)
E
8a,c
O
O
Scheme 5 Structure of the cation E resulting from the hypothetical
ionization of the tosylate 1b
8a, R = H:
8c, R = (CH2)5OTBDMS:
11a, 78%
11c, 65%
Scheme 6 Synthesis of various polyoxygenated tricyclic products
The reduction of anhydride 2c, with syn structure, mainly
occurred with the loss of the TBDMS protective group to
give triol 9. It is well known that the presence of a reduc-
ible group near the TBDMS-protected alcohol promotes
deprotection. Moreover, for the minor product 7c, the
TBDMS group was transferred to a hydroxymethyl group
(following the formation of a cyclic pentavalent silicon
anion intermediate).13
In summary, we have shown that the spirocyclopentadie-
nyl alcohol 1a, easily obtained from generally available
reagents, gives access to various polyoxygenated tricyclic
compounds with good control of the stereochemistry. The
spirocyclopentadienyl tosylate 1b presented special be-
havior in the course of solvolytic displacement reactions.
THF was freshly distilled from Na/benzophenone; CH2Cl2 and py-
ridine from CaH2 under argon. Other reagents and solvents were ob-
tained from commercial sources and used as received. All
experiments were conducted under an atmosphere of argon. Flash
column chromatography (FC): Merck 230–400 mesh silica gel;
EtOAc, Et2O, and petroleum ether (PE) as eluents. TLC: Macherey-
Nagel silica gel UV254 analytical plate. NMR spectroscopy: Bruker
AC 300 (1H, 300 MHz; 13C, 75 MHz); relative to CDCl3 (signals for
residual CHCl3 in the CDCl3: d = 7.26 (1H) and 77.00 (central, 13C).
Carbon–proton couplings were determined by DEPT sequence ex-
periments. MS: Applied Biosystems SCIEX QStar Elite. Mp: un-
corrected, Büchi capillary apparatus. Products 2, 3, 7, 8, 10, and 11
all had the following relative configuration, (1S*,2R*,3S*,4R*).
Figure 2 LUMO (29th MO)(up) and HOMO (28th MO)(down) of
the cation E (B3LYP/6-311G++(3df,3pd) level of theory)
From the Diels–Alder adducts 2a,c, some polyoxygenated
tricyclic products of synthetic interest for the preparation
of polypodal ligands can be easily obtained (Scheme 6).
Synthesis 2011, No. 4, 674–680 © Thieme Stuttgart · New York

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Stereoselective Synthesis of Spiro Tricyclic Polyoxygenated Compounds
677
Spiro[2.4]hepta-4,6-diene-1-methanol (1a)
crude product was filtered, concentrated in vacuo and flash chro-
matographed (silica gel, Et2O) to give the syn-isomer 2a (1.56 g, 7.1
mmol, 29%) as a white powder and then the anti-isomer 3a (2.09 g,
9.5 mmol, 39%) also as a white powder (CAS 52497-51-5).
Freshly distilled cyclopentadiene (1.12 g, 17.0 mmol) was added
dropwise to a soln of 2.5 M BuLi in hexane (8.7 mL, 21.6 mmol) in
anhyd THF (40 mL) stirred at –20 °C. The mixture was stirred for
0.5 h and then epichlorohydrin (0.45 mL, 5.40 mmol) was slowly
added. The soln was stirred at 0 °C for 18 h and then cooled to –10
°C and H2O (40 mL) and Et2O (40 mL) were added successively.
The organic phase was stirred with brine and then it was separated,
dried (MgSO4), filtered, and concentrated in vacuo. The crude prod-
uct was flash chromatographed (silica gel, PE–EtOAc, 70:30) to
give 1a (371 mg, 3.04 mmol, 56%) as a yellow oil.
1H NMR (300 MHz, CDCl3): d = 6.61 (dt, J = 5.3, 1.8 Hz, 1 H), 6.48
(dt, J = 5.2, 1.7 Hz, 1 H), 6.25 (dt, J = 5.2, 1.7 Hz, 1 H), 6.09 (dt,
J = 5.0, 1.7 Hz, 1 H), 3.97 (dd, J = 11.7, 6.0 Hz, 1 H), 3.58 (dd,
J = 11.7, 8.5 Hz, 1 H), 2.47–2.37 (m, 1 H), 1.85 (dd, J = 8.6, 4.3 Hz,
1 H), 1.67 (dd, J = 7.1, 4.3 Hz, 1 H).
syn-Isomer 2a
Mp 142 °C.
1H NMR (300 MHz, CDCl3): d = 6.39 (ddd, J = 5.8, 2.8, 1.0 Hz, 1
H), 6.35 (ddd, J = 5.8, 2.8, 1.0 Hz, 1 H), 4.01 (dd, J = 8.1, 4.8 Hz, 1
H), 3.92 (dd, J = 11.0, 5.3 Hz, 1 H), 3.73 (dd, J = 8.1, 4.8 Hz, 1 H),
3.20 (dd, J = 11.0, 9.5, Hz, 1 H), 3.16 (m, 1 H), 2.90–2.87 (m, 1 H),
1.24–1.13 (m, 1 H), 0.76 (dd, J = 9.0, 5.9 Hz, 1 H), 0.44 (t, J = 5.6
Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 171.5 (s), 171.4 (s), 135.3 (d),
135.0 (d), 63.6 (t), 53.2 (s), 51.5 (d), 47.3 (d, 2 C), 47.2 (d), 22.6 (d),
10.1 (t).
13C NMR (75 MHz, CDCl3): d = 139.4 (d), 133.9 (d), 131.7 (d),
128.6 (d), 64.9 (t), 41.9 (s), 30.0 (t), 17.6 (d).
anti-Isomer 3a
Mp 128 °C.
1-(Tosyloxymethyl)spiro[2.4]hepta-4,6-diene (1b)
1H NMR (300 MHz, CDCl3): d = 6.35 (t, J = 3.9 Hz, 2 H), 3.67 (m,
2 H), 3.51 (dd, J = 11.4, 6.8, Hz, 1 H), 3.32 (dd, J = 11.4, 7.6, Hz, 1
H), 3.12 (br sext, J = 2.0 Hz, 1 H), 2.86 (br sext, J = 2.0 Hz, 1 H),
1.28 (br sext, J = 7.2 Hz, 1 H), 0.69 (dd, J = 8.8, 5.7 Hz, 1 H), 0.41
(t, J = 5.6 Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 171.1 (s, 2 C), 135.8 (d), 135.4 (d),
63.3 (t), 52.8 (s), 51.1 (d), 47.1 (d), 46.9 (d), 46.6 (d), 21.5 (d), 12.0
(t).
To a cooled soln (–20 °C) of alcohol 1a (1.11 g, 9.12 mmol) in an-
hyd pyridine (20 mL) was added TsCl (3.47 g, 18.2 mmol); the soln
was stirred for 5 h. The mixture was poured onto ice and extracted
with Et2O (3 × 60 mL). The combined organic phase was washed
with 1 M HCl (60 mL) and aq 10% CuSO4 (50 mL), dried (MgSO4),
and then concentrated in vacuo to give 1b (2.39 g, 8.66 mmol, 95%)
as an oil, which was used in the following steps without further pu-
rification.
1H NMR (300 MHz, CDCl3): d = 7.76 (d, J = 8.1 Hz, 2 H), 7.32 (d,
J = 8.1 Hz, 2 H), 6.50 (m, 1 H), 6.44 (m, 1 H), 5.99 (m, 2 H), 4.21
(dd, J = 10.7, 8.0 Hz, 1 H), 4.12 (dd, J = 10.7, 7.0 Hz, 1 H), 2.44 (s,
3 H), 2.33 (quint, J = 7.6 Hz, 1 H), 1.79 (dd, J = 8.5, 4.7 Hz, 1 H),
1.58 (dd, J = 6.7, 4.7 Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 144.9 (s), 138.4 (d), 133.5 (d),
131.6 (d), 129.8 (d, 2 C), 129.3 (d), 127.8 (d, 2 C), 72.0 (t), 41.5 (s),
24.7 (d), 21.6 (q), 17.0 (t).
Anal. Calcd for C12H12O4 (220.22): C, 65.45; H, 5.49. Found: C,
65.41; H, 5.55.
(2¢-syn)- (2b) and (2¢-anti)-2¢-(Tosyloxymethyl)spiro[bicyc-
lo[2.2.1]hept-5-ene-7,1¢-cyclopropane]-2,3-dicarboxylic Anhy-
dride (3b); Typical Procedure
Tosylate 1b (200 mg, 0.72 mmol) in anhyd CH2Cl2 (2 mL) was add-
ed to a soln of maleic anhydride (96.0 mg, 0.98 mmol) in anhyd
CH2Cl2 (10 mL). The mixture was stirred at r.t. for 24 h, the solvent
was eliminated in vacuo, and the crude product was flash chromato-
graphed (silica gel, PE–EtOAc, 70:30) to give syn-isomer 2b (59
mg, 0.16 mmol, 22%) and then anti-isomer 3b (140 mg, 0.37 mmol,
52%).
1-{[5-(tert-Butyldimethylsiloxy)pentyloxy]meth-
yl}spiro[2.4]hepta-4,6-diene (1c)
To a suspension of NaH (4.92 g, 123 mmol) in anhyd THF (100 mL)
cooled to 0 °C was added dropwise 1a (10.0 g, 82.0 mmol) in anhyd
THF (75 mL) and TBAI (2.20 g). The mixture was stirred for 1 h,
1-(tert-butyldimethylsiloxy)-5-bromopentane (CAS 85514-43-8)
(32.7 g, 123 mmol) was added dropwise, and the soln was refluxed
for 24 h. After usual workup (CH2Cl2), the crude product was flash
chromatographed (silica gel, PE–EtOAc, 90:10 to 70:30) to give 1c
(14.5 g, 45 mmol, 55%) as a yellow oil.
1H NMR (300 MHz, CDCl3): d = 6.55 (dt, J = 5.2, 1.8 Hz, 1 H), 6.47
(dt, J = 5.0, 1.8 Hz, 1 H), 6.24 (dt, J = 5.2, 1.8 Hz, 1 H), 6.22 (dt,
J = 5.2, 1.8 Hz, 1 H), 3.62–3.57 (m, 4 H), 3.56–3.38 (m, 2 H), 2.39–
2.29 (m, 1 H), 1.77 (dd, J = 8.6, 4.2 Hz, 1 H), 1.67 (dd, J = 7.2, 4.2
Hz, 1 H), 1.64–1.46 (m, 4 H), 1.42–1.32 (m, 2 H), 0.87 (s, 9 H), 0.02
(s, 6 H).
syn-Isomer 2b
Mp 121 °C.
1H NMR (300 MHz, CDCl3): d = 7.79 (d, J = 8.1 Hz, 2 H), 7.38 (d,
J = 8.1 Hz, 2 H), 6.36 (m, 2 H), 4.39 (dd, J = 11.0, 5.3 Hz, 1 H),
3.82 (dd, J = 8.2, 4.7 Hz, 1 H), 3.67 (dd, J = 8.2, 4.7 Hz, 1 H), 3.50
(t, J = 10.7 Hz, 1 H), 2.97 (m, 1 H), 2.88 (m, 1 H), 2.47 (s, 3 H),
1.42–1.29 (m, 1 H), 0.88 (dd, J = 9.1, 6.1 Hz, 1 H), 0.48 (t, J = 5.7
Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 170.8 (s), 170.7 (s), 145.2 (s),
135.2 (d), 134.8 (d), 132.4 (s), 130.0 (d, 2 C), 127.6 (d, 2 C), 71.6
(t), 53.0 (s), 50.9 (d), 47.1 (d), 46.6 (d), 46.57 (d), 21.4 (d), 19.3 (q),
10.6 (t).
13C NMR (75 MHz, CDCl3): d = 139.3 (d), 134.9 (d), 130.6 (d),
128.6 (d), 72.0 (t), 70.6 (t), 63.1 (t), 41.7 (s), 32.6 (t), 29.4 (t), 26.9
(d), 26.0 (q, 3 C), 22.4 (t), 18.3 (s), 17.5 (t), –5.3 (q, 2 C).
anti-Isomer 3b14
Mp 99 °C.
Anal. Calcd for C19H34O2Si (322.56): C, 70.75; H, 10.62. Found: C,
70.65; H, 10.55.
1H NMR (300 MHz, CDCl3): d = 7.76 (d, J = 8.2 Hz, 2 H), 7.35 (d,
J = 8.2 Hz, 2 H), 6.33 (br quint, J = 4.75 Hz, 2 H), 4.02 (dd,
J = 10.7, 7.3, 1 H), 3.79 (dd, J = 10.7, 8.07, 1 H), 3.66 (d, J = 2.3
Hz, 1 H), 3.65 (d, J = 2.3 Hz, 1 H), 2.98 (br s, 1 H), 2.88 (br s, 1 H),
2.46 (s, 3 H), 1.40 (qd, J = 8.0, 5.3 Hz, 1 H), 0.81 (dd, J = 8.8, 6.1
Hz, 1 H), 0.50 (t, J = 5.7 Hz, 1 H).
(2¢-syn)- (2a) and (2¢-anti)-2¢-(Hydroxymethyl)spiro[bicyc-
lo[2.2.1]hept-5-ene-7,1¢-cyclopropane]-2,3-dicarboxylic Anhy-
dride (3a)
Hydroxymethyl spiro derivative 1a (3.00 g, 24.6 mmol) was added
to a stirred soln at 0 °C of maleic anhydride (3.40 g, 34.7 mmol) in
CH2Cl2 (150 mL). The mixture was stirred at 20 °C for 1 d; the
13C NMR (75 MHz, CDCl3): d = 170.7 (s), 170.5 (s), 145.0 (s),
135.4 (d), 134.9 (d), 132.9 (s), 129.8 (d, 2 C), 127.7 (d, 2 C), 71.4
Synthesis 2011, No. 4, 674–680 © Thieme Stuttgart · New York

678
C. Reynaud et al.
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(t), 52.9 (s), 50.9 (d), 46.9 (d), 46.8 (d), 46.5 (d), 21.5 (d), 18.0 (q),
12.9 (t).
13C NMR (75 MHz, CDCl3): d = 138.6 (d), 133.5 (d), 131.7 (d),
129.3 (d), 45.7 (s), 35.1 (t), 29.5 (d), 20.6 (t).
Anal. Calcd for C19H18O6S (374.41): C, 60.95; H, 4.85. Found: C,
61.01; H, 4.75.
1-Formylspiro[2.4]hepta-4,6-diene (6)
NaHCO3 (124 mg, 1.47 mmol) and 1b (300 mg, 1.09 mmol) in an-
hyd DMSO (8 mL) were stirred and heated at 80 °C for 5 h. The res-
idue was poured onto ice and after the usual workup (Et2O), the
crude product was flash chromatographed (silica gel, PE–EtOAc,
80:20) to give 6 (unstable) (26 mg, 0.218 mmol, 20%) as an oil.
1H NMR (300 MHz, CDCl3): d = 9.43 (s, 1 H), 6.55 (m, 2 H), 6.33
(m, 1 H), 6.02 (m, 1 H), 2.33 (m, 1 H), 1.60 (m, 2 H).
(2¢-syn)- (2c) and (2¢-anti)-2¢-{[5-(tert-Butyldimethylsiloxy)pen-
tyloxy]methyl}spiro[bicyclo[2.2.1]hept-5-ene-7,1¢-cyclopro-
pane]-2,3-dicarboxylic Anhydride (3c)
Following the typical procedure for 2b/3b using 1c (232 mg, 0.72
mmol) gave, after flash chromatography on silica gel (PE–EtOAc,
80:20), syn-isomer 2c (103 mg, 0.24 mmol, 34%) as an oil and then
anti-isomer 3c (85.0 mg, 0.20 mmol, 28%) also as an oil.
13C NMR (75 MHz, CDCl3): d = 197.5 (d), 136.6 (d), 132.6 (d),
132.0 (d), 131.1 (d), 45.6 (s), 35.1 (d), 16.6 (t).
syn-Isomer 2c
1H NMR (300 MHz, CDCl3): d = 6.36 (m, 2 H), 3.68 (dd, 8.3, 4.7
Hz, 2 H), 3.60 (t, J = 6.4 Hz, 2 H), 3.44–3.32 (m, 2 H), 3.11 (br s, 1
H), 2.93 (t, J = 10.0 Hz, 1 H), 2.86 (br s, 1 H), 1.54 (sept, J = 7.0 Hz,
4 H), 1.41–1.33 (m, 2 H), 1.25–1.15 (m, 2 H), 0.88 (s, 9 H), 0.78
(dd, J = 9.0, 5.8 Hz, 1 H), 0.42 (t, J = 5.6 Hz, 1 H), 0.03 (s, 6 H).
(2¢-syn)- (7a) and (2¢-anti)-2,2¢,3-Tris(hydroxymethyl)spiro[bi-
cyclo[2.2.1]hept-5-ene-7,1¢-cyclopropane] (8a); Typical Proce-
dure
To a stirred suspension of LiAlH4 (280 mg, 7.38 mmol) in anhyd
THF (10 mL) at –20 °C was added dropwise a soln of 2a or 3a (440
mg, 2 mmol) in THF (5 mL); the mixture was refluxed for 3 h. After
cooling to –20 °C, H2O (0.28 mL), 1 M NaOH (0.28 mL), and H2O
(0.84 mL) were added successively. The suspension was stirred for
2 h and then filtered (salts were washed with Et2O, 3 ×) concentrat-
ed in vacuo and flash chromatographed (silica gel, MeOH–CH2Cl2,
2:98) to give syn-isomer 7a or anti-isomer 8a (327 mg, 1.56 mmol,
78%) as a yellow oil.
13C NMR (75 MHz, CDCl3): d = 171.4 (s), 171.3 (s), 135.3 (d),
135.0 (d), 71.7 (t), 71.1 (t), 63.0 (t), 53.0 (s), 51.5 (d), 47.4 (d), 47.2
(d), 47.1 (d), 32.5 (t), 29.5 (t), 25.9 (q, 3 C), 22.5 (t), 20.5 (d), 18.3
(s), 10.2 (t), –5.3 (q, 2 C).
anti-Isomer 3c
1H NMR (300 MHz, CDCl3): d = 6.37 (m, 2 H), 3.68 (dd, J = 3.0,
1.6 Hz, 2 H), 3.42–3.20 (m, 6 H), 3.11 (br s, 1 H), 2.89 (br s, 1 H),
1.59–1.47 (m, 2 H), 1.39–1.31 (m, 3 H), 1.70 (m, 2 H), 0.88 (s, 9 H),
0.72 (dd, J = 8.8, 5.6 Hz, 1 H), 0.45 (t, J = 5.6 Hz, 1 H), 0.03 (s, 6
H).
syn-Isomer 7a
1H NMR (300 MHz, CDCl3): d = 6.13 (m, 2 H), 3.73–3.59 (m, 6 H),
3.42 (m, 4 H), 2.48 (s, 1 H), 2.17 (s, 1 H), 0.63 (m, 2 H), 0.26 (t,
J = 5.1 Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 171.0 (s, 2 C), 135.7 (d), 134.8 (d),
71.2 (t), 70.7 (t), 63.0 (t), 52.6 (s), 51.4 (d), 47.3 (d), 47.2 (d), 46.8
(d), 32.6 (t), 29.4 (t), 25.9 (q, 3 C), 22.4 (t), 19.4 (d), 18.3 (s), 12.6
(t), –5.3 (q, 2 C).
13C NMR (75 MHz, CDCl3): d = 134.4 (d), 134.3 (d), 63.7 (t), 62.9
(t), 62.8 (t), 52.2 (d), 49.9 (s), 47.9 (d), 45.9 (d), 45.8 (d), 22.7 (d),
9.5 (t).
Anal. Calcd for C23H36O5Si (420.61): C, 65.68; H, 8.63. Found: C,
65.61; H, 8.75.
anti-Isomer 8a
1H NMR (300 MHz, CDCl3): d = 6.14 (t, J = 2.9 Hz, 2 H), 3.54–3.32
(m, 7 H), 3.24 (dd, J = 11.1, 8.2 Hz, 2 H), 2.62 (m, 2 H), 2.39 (br s,
1 H), 2.18 (br s, 1 H), 0.62 (dd, J = 8.5, 5.5 Hz, 2 H), 0.30 (t, J = 5.2
Hz, 1 H).
Bicyclo[3.3.0]octa-1,4-dien-7-ol (4)
Li2CO3 (0.64 g, 8.6 mmol) and tosylate 1b (1.0 g, 3.62 mmol) in
THF (20 mL) and H2O (20 mL) were refluxed for 6 h, cooled to 20
°C, and filtered. After usual workup (Et2O), the crude product was
flash chromatographed (silica gel, PE–EtOAc, 70:30) to give 4 (194
mg, 1.60 mmol, 44%) as a yellow oil and 1a (152 mg, 1.24 mmol,
34%).
13C NMR (75 MHz, CDCl3): d = 136.6 (d), 134.4 (d), 64.6 (t), 62.9
(t), 62.8 (t), 52.1 (d), 49.6 (s), 47.1 (d), 45.7 (d), 45.2 (d), 20.8 (d),
12.0 (t).
Anal. Calcd for C12H18O3 (210.27): C, 68.54; H, 8.63. Found: C,
68.51; H, 8.55.
1H NMR (300 MHz, CDCl3): d = 5.93 (m, 2 H), 4.74 (quint, J = 5.0
Hz, 1 H), 2.82–2.72 (m, 2 H), 2.48–2.38 (m, 4 H).
(2¢-syn)- (7c) and (2¢-anti)-2¢-{[5-(tert-Butyldimethylsiloxy)pen-
tyloxy]methyl}-2,3-bis(hydroxymethyl)spiro[bicyc-
lo[2.2.1]hept-5-ene-7,1¢-cyclopropane] (8c) and 2,3-
Bis(hydroxymethyl)-2¢-[(5-hydroxypentyloxy)methyl]spiro[bi-
cyclo[2.2.1]hept-5-ene-7,1¢-cyclopropane] (9)
13C NMR (75 MHz, CDCl3): d = 150.1 (s) (2 C), 121.3 (d, 2 C), 77.9
(d), 46.7 (t), 35.8 (t, 2 C).
Anal. Calcd for C8H10O (120.16): C, 78.65; H, 8.25. Found: C,
78.61; H, 8.35.
Following the typical procedure for 8a using 3c (841 mg, 2 mmol),
but the soln was stirred at r.t. for 8 h to give, after flash chromatog-
raphy on silica gel (MeOH–CH2Cl2, 5:95), 8c (510 mg, 1.24 mmol,
62%) as an oil.
1-(Bromomethyl)spiro[2.4]hepta-4,6-diene (5)
LiBr (434 mg, 5 mmol) and 1b (244 mg, 1 mmol) in anhyd THF (5
mL) were stirred at 25 °C for 3 d. Then the mixture was concentrat-
ed in vacuo. To the residue, H2O and CH2Cl2 were added; after de-
cantation, the aqueous fraction was extracted with CH2Cl2. The
organic layers were dried (MgSO4), filtered, and concentrated in
vacuo. The crude product was then subjected to flash chromatogra-
phy on silica gel (pentane) to give 5 (184 mg, 0.95 mmol, 95%) as
an oil.
1H NMR (300 MHz, CDCl3): d = 6.61 (dt, J = 5.2, 1.8 Hz, 1 H), 6.50
(dt, J = 5.1, 1.7 Hz, 1 H), 6.20 (dt, J = 5.2, 1.7 Hz, 1 H), 6.07 (dt,
J = 5.1, 1.7 Hz, 1 H), 3.64–3.52 (m, 2 H), 2.61–2.51 (m, 1 H), 1.97
(dd, J = 8.5, 4.7 Hz, 1 H), 1.71 (dd, J = 7.0, 4.7 Hz, 1 H).
Following the typical procedure for 8a using 2c with the same con-
ditions, gave 7c (164 mg, 0.4 mmol, 20%) and triol 9 (237 mg, 0.8
mmol, 40%). 7c appeared as a mixture because the tert-butyldi-
methylsiloxy group was distributed on various positions.
anti-Isomer 8c
1H NMR (300 MHz, CDCl3): d = 6.06 (m, 2 H), 3.55 (t, J = 6.4 Hz,
4 H), 3.44–3.14 (m, 4 H), 2.63 (br d, J = 5.9 Hz, 2 H), 2.33 (br s, 1
H), 2.14 (br s, 1 H), 1.56–1.44 (m, 5 H), 1.36–1.28 (m, 2 H), 1.16–
Synthesis 2011, No. 4, 674–680 © Thieme Stuttgart · New York

PAPER
Stereoselective Synthesis of Spiro Tricyclic Polyoxygenated Compounds
679
1.06 (m, 2 H), 0.85 (s, 9 H), 0.62 (dd, J = 8.4, 5.4 Hz, 1 H), 0.29 (t,
J = 5.2 Hz, 1 H), 0.00 (s, 6 H).
9 H), 0.64 (dd, J = 8.3, 5.3 Hz, 1 H), 0.31 (t, J = 5.3 Hz, 1 H), 0.02
(s, 6 H).
13C NMR (75 MHz, CDCl3): d = 134.8 (d), 134.2 (d), 72.2 (t), 70.3
(t), 63.1 (t), 62.73 (t), 62.67 (t), 52.0 (d), 49.0 (s), 47.3 (d), 45.6 (d),
45.0 (d), 32.5 (t), 29.3 (t), 25.9 (q, 3 C), 22.3 (t), 18.3 (s), 18.2 (d),
12.5 (t), –5.4 (q, 2 C).
13C NMR (75 MHz, CDCl3): d = 135.0 (d), 134.4 (d), 101.2 (s), 72.2
(t), 70.4 (t), 64.7 (t), 64.6 (t), 63.1 (t), 51.2 (s), 50.7 (d), 46.6 (d),
45.7 (d), 45.2 (d), 32.6 (t), 29.4 (t), 25.9 (q, 3 C), 24.4 (q), 22.4 (t),
19.7 (q), 18.3 (s), 18.2 (d), 12.5 (t), –5.3 (q, 2 C).
Anal. Calcd for C23H42O4Si (410.66): C, 67.27; H, 10.31. Found: C,
67.22; H, 10.35.
Anal. Calcd for C26H46O4Si (450.73): C, 69.28; H, 10.29. Found: C,
69.48; H, 10.35.
syn-Hydroxy Derivative 9
1H NMR (300 MHz, CDCl3): d = 6.10 (m, 2 H), 3.64–3.56 (m, 4 H),
3.53–3.30 (m, 6 H), 3.13 (dd, J = 10.0, 9.0 Hz, 1 H), 2.86 (m, 1 H),
2.73 (m, 1 H), 2.41 (br s, 1 H), 2.14 (br s, 1 H), 1.66–1.45 (m, 8 H),
1.12 (m, 1 H), 0.61 (dd, J = 8.8, 5.1 Hz, 1 H), 0.24 (t, J = 5.2 Hz, 1
H).
Acknowledgment
C.R. thanks Dr S. Goldstein for helpful comments and the Institut
de Recherche Servier (Suresnes, Fr 92150) for financial support.
This work has been financially supported by the CNRS and the
Ministère de l’Enseignement Supérieur et de la Recherche.
13C NMR (75 MHz, CDCl3): d = 134.45 (d), 134.42 (d), 72.0 (t),
70.4 (t), 62.8 (t, 2 C), 62.5 (t), 53.4 (s), 52.3 (d), 49.6 (s), 47.9 (d),
45.76 (d), 45.3 (d), 32.3 (t), 29.4 (t), 23.1 (t), 19.9 (d), 9.4 (t).
References
Anal. Calcd for C17H28O4 (296.40): C, 68.89; H, 9.52. Found: C,
68.95; H, 9.48.
(1) (a) Laurenti, D.; Feuerstein, M.; Pèpe, G.; Doucet, H.;
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(2¢-syn)- (10a) and (2¢-anti)-2¢,2,3-Tris(hydroxymethyl)spiro[bi-
cyclo[2.2.1]hept-5-ene-7,1¢-cyclopropane] Acetonide (11a);
Typical Procedure
(2) Reynaud, C.; Fall, Y.; Feuerstein, M.; Doucet, H.; Santelli,
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(3) (a) Bangert, K.; Boekelheide, V. Tetrahedron Lett. 1963, 4,
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To a soln of 7a or 8a (210 mg, 1 mmol) in anhyd CH2Cl2 (5 mL)
was added 2-methoxypropene (0.2 mL, 2.03 mmol) and some crys-
tals of 10-camphorsulfonic acid. The soln was stirred until comple-
tion of the reaction (TLC, PE–EtOAc, 50:50). Anhyd K2CO3 (ca. 50
mg) was added and the soln was stirred, filtered, and concentrated
in vacuo. The crude product was flash chromatographed (silica gel,
PE–EtOAc, 50:50) to give 10a (180 mg, 0.72 mmol, 72%) or 11a
(195 mg, 0.78 mmol, 78%).
syn-Isomer 10a
1H NMR (300 MHz, CDCl3): d = 6.16 (br s, 2 H), 3.73–3.60 (m, 4
H), 3.41 (t, J = 12.7 Hz, 2 H), 3.27 (dd, J = 11.0, 8.4 Hz, 1 H), 2.80–
2.62 (m, 2 H), 2.32 (s, 1 H), 2.06 (s, 1 H), 1.30 (s, 3 H), 1.29 (s, 3
H), 0.59 (dd, J = 8.5, 5.2 Hz, 1 H), 0.29 (t, J = 5.1 Hz, 1 H).
13C NMR (75 MHz, CDCl3): d = 134.5 (d), 134.4 (d), 101.2 (s), 64.4
(t, 2 C), 63.3 (t), 51.4 (d), 50.9 (s), 47.1 (d), 45.8 (d), 45.6 (d), 29.6
(q), 22.7 (d), 19.6 (q), 9.9 (t).
anti-Isomer 11a
1H NMR (300 MHz, CDCl3): d = 6.29 (dd, J = 5.8, 2.8, Hz, 1 H),
6.25 (dd, J = 5.8, 2.7, Hz, 1 H), 3.73–3.64 (m, 4 H), 3.50–3.40 (m,
2 H), 3.14 (dd, J = 11.1, 9.0 Hz, 1 H), 2.82–2.76 (m, 2 H), 2.34 (br
s, 1 H), 2.13 (br s, 1 H), 1.34 (s, 3 H), 1.33 (s, 3 H), 0.66 (dd, J = 8.6,
5.6 Hz, 1 H), 0.33 (t, J = 5.4 Hz, 1 H).
(4) For example, for syn-isomers 2a and 2c, the chemical shifts
of carbon atoms of anhydrides are different, and for anti-
isomers 3a and 3c the chemical shifts are identical.
(5) Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.;
Robb, M. A.; Cheeseman, J. R.; Montgomery, J. A. Jr.;
Vreven, T.; Kudin, K. N.; Burant, J. C.; Millam, J. M.;
Iyengar, S. S.; Tomasi, J.; Barone, V.; Mennucci, B.; Cossi,
M.; Scalmani, G.; Rega, N.; Petersson, G. A.; Nakatsuji, H.;
Hada, M.; Ehara, M.; Toyota, K.; Fukuda, R.; Hasegawa, J.;
Ishida, M.; Nakajima, T.; Honda, Y.; Kitao, O.; Nakai, H.;
Klene, M.; Li, X.; Knox, J. E.; Hratchian, H. P.; Cross, J. B.;
Bakken, V.; Adamo, C.; Jaramillo, J.; Gomperts, R.;
Stratmann, R. E.; Yazyev, O.; Austin, A. J.; Cammi, R.;
Pomelli, C.; Ochterski, J. W.; Ayala, P. Y.; Morokuma, K.;
Voth, G. A.; Salvador, P.; Dannenberg, J. J.; Zakrzewski, V.
G.; Dapprich, S.; Daniels, A. D.; Strain, M. C.; Farkas, O.;
Malick, D. K.; Rabuck, A. D.; Raghavachari, K.; Foresman,
J. B.; Ortiz, J. V.; Cui, Q.; Baboul, A. G.; Clifford, S.;
Cioslowski, J.; Stefanov, B. B.; Liu, G.; Liashenko, A.;
Piskorz, P.; Komaromi, I.; Martin, R. L.; Fox, D. J.; Keith,
T.; Al-Laham, M. A.; Peng, C. Y.; Nanayakkara, A.;
13C NMR (75 MHz, CDCl3): d = 136.8 (d), 134.5 (d), 101.3 (s),
64.56 (t), 64.54 (t), 64.5 (t), 51.2 (d), 51.2 (s), 46.3 (d), 45.7 (d), 45.1
(d), 29.7 (q), 20.8 (d), 19.7 (q), 12.0 (t).
Anal. Calcd for C15H22O3 (250.33): C, 71.97; H, 8.86. Found: C,
71.88; H, 8.85.
2¢-{[5-(tert-Butyldimethylsiloxy)pentyloxy]methyl}-2,3-bis(hy-
droxymethyl)spiro[bicyclo[2.2.1]hept-5-ene-7,1¢-cyclopro-
pane] Acetonide (11c)
Following the typical procedure for 11a using 8c (411 mg, 1 mmol)
gave, after chromatiography on silica gel (PE–Et2O, 50:50), 11c
(293 mg, 0.65 mmol, 65%).
1H NMR (300 MHz, CDCl3): d = 6.17 (t, J = 1.8 Hz, 2 H), 3.72–3.64
(m, 2 H), 3.57 (t, J = 6.4 Hz, 2 H), 3.51–3.16 (m, 4 H), 2.77 (br d,
J = 9.0 Hz, 2 H), 2.28 (br s, 1 H), 2.08 (br s, 1 H), 1.58–1.45 (m, 5
H), 1.35 (s, 3 H), 1.33 (s, 3 H), 1.27 (m, 2 H), 1.10 (m, 2 H), 0.87 (s,
Synthesis 2011, No. 4, 674–680 © Thieme Stuttgart · New York

680
C. Reynaud et al.
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data can be obtained free of charge at www.ccdc.cam.ac.uk/
conts/retrieving.html [or from the Cambridge
Crystallographic Data Centre, 12 Union Road, Cambridge
CB2 1EZ, UK; fax: +44 (1223)336033; or e-mail:
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Synthesis 2011, No. 4, 674–680 © Thieme Stuttgart · New York