Reactions of (η5-C5H5)(CO)2Fe-substituted N-sulfonyl azadienes with C-nucleophiles. A route to 5-substituted dihydropyrrolones

Article abstract of DOI:10.1021/om000235j

A variety of cyclic β-[(η⁵-C₅H₅)(CO)₂Fe]-substituted N-sulfonyl azadienes 4 were prepared: e.g., from the corresponding iron-substituted (Z)-enals and benzenesulfonamide. Reactions of these iron compounds with Grignard reagents or organolithiums gave 5-substituted α,β-unsaturated N-sulfonyl γ-lactams 5. In some cases the corresponding non-N-protected 5-substituted γ-lactams 6 were isolated as well. Key steps of these reaction cascades are the initial 1,2-addition to the imine moiety and the subsequent carbonylation step. The reaction of the chromene-iron complex 4e with (allyl)MgCl gave the (η³-allyl)-iron-γ-lactam complex 8a with a ring-opened chromene framework. This complex was structurally characterized by X-ray analysis.

Full text of DOI:10.1021/om000235j

Organometallics 2000, 19, 3527-3534
3527
Rea ction s of (η5-C5H5)(CO)2F e-Su bstitu ted N-Su lfon yl
Aza d ien es w ith C-Nu cleop h iles. A Rou te to 5-Su bstitu ted
Dih yd r op yr r olon es
P. Amrhein, D. Schollmeyer, and Karola Ru¨ck-Braun*
Institut fu¨r Organische Chemie, J ohannes Gutenberg-Universita¨t Mainz,
Duesbergweg 10-14, 55099 Mainz, Germany
Received March 16, 2000
A variety of cyclic â-[(η5-C5H5)(CO)2Fe]-substituted N-sulfonyl azadienes 4 were pre-
pared: e.g., from the corresponding iron-substituted (Z)-enals and benzenesulfonamide.
Reactions of these iron compounds with Grignard reagents or organolithiums gave
5-substituted R,â-unsaturated N-sulfonyl γ-lactams 5. In some cases the corresponding non-
N-protected 5-substituted γ-lactams 6 were isolated as well. Key steps of these reaction
cascades are the initial 1,2-addition to the imine moiety and the subsequent carbonylation
step. The reaction of the chromene-iron complex 4e with (allyl)MgCl gave the (η3-allyl)-
iron-γ-lactam complex 8a with a ring-opened chromene framework. This complex was
structurally characterized by X-ray analysis.
Sch em e 1a
In tr od u ction
Transition-metal-mediated cyclocarbonylations have
attracted a great deal of interest in recent years in
catalytic as well as stoichiometric processes.1-3 Recently,
we reported on novel cyclocarbonylations of â-[(η5-
C5H5)(CO)2Fe]-substituted (Z)-enals leading to γ-lac-
tones and γ-lactams in one-pot procedures.4-6 These
reaction cascades involve the addition of an organome-
tallic reagent (e.g., K-Selectride,5 RMgCl, or RLi6) or the
TiCl4-mediated addition of electron-rich primary amines4
to the aldehyde functionality as the initial key step. In
this paper reactions of â-[(η5-C5H5)(CO)2Fe]-substituted
N-sulfonyl azadienes with organolithiums and Grignard
reagents furnishing 5-substituted dihydropyrrolones are
presented.
Resu lts a n d Discu ssion
There are two synthetic routes to [(η5-C5H5)(CO)2Fe]-
substituted N-sulfonyl azadienes 4; both start from
â-bromo enals 1 as shown in Scheme 1. The cyclic
N-sulfonyl imines 4 are accessible from the (η5-C5H5)-
(CO)2Fe-substituted enals 2 and benzenesulfonamide by
the use of titanium tetrachloride and triethylamine in
almost quantitative yield (route A).4,7 The iron com-
a
Route A: (a) 1, [Cp(CO)2Fe]Na, THF; (b) 2, benzene-
sulfonamide, TiCl4, NEt3, CH2Cl2, 4, quantitative yield. Route
B: (a) 1a , benzenesulfonamide, TiCl4, NEt3, CH2Cl2, 3a ,
quantitative yield; (b) 3a , [Cp(CO)2Fe]Na, THF, 4a , 67% yield.
(1) Donohoe, T. J .; Harji, R. R.; Moore, P. R.; Warning, M. J . J .
Chem. Soc., Perkin Trans. 1 1999, 1377-1395.
(2) Comely, A. C.; Gibson (ne´e Thomas), S. E. J . Chem. Soc., Perkin
Trans. 1 1998, 819-834.
(3) Shieh, S.-J.; Liang, K.-W.; Li, W.-T.; Shu, L.-H.; Chandrasekharam,
M.; Liu, R.-S. Pure Appl. Chem. 1998, 70, 1111-1115.
(4) (a) Ru¨ck-Braun, K. Angew. Chem. 1997, 109, 526-528; Angew.
Chem., Int. Ed. Engl. 1997, 36, 509-511. (b) Ru¨ck-Braun, K.; Martin,
T.; Mikula´s, M. Chem. Eur. J . 1999, 5, 1028-1037.
(5) Ru¨ck-Braun, K.; Mo¨ller, C. Chem. Eur. J . 1999, 5, 1038-1044.
(6) (a) Mo¨ller, C.; Mikula´s, M.; Wierschem, F.; Ru¨ck-Braun, K.
Synlett 2000, 182-184. (b) Mikula´s, M.; Rust, S.; Schollmeyer, D.;
Ru¨ck-Braun, K. Synlett 2000, 185-188.
(7) (a) Weingarten, H.; Chupp, J . P.; White, W. A. J . Org. Chem.
1967, 32, 3246-3249. (b) J ennings, W. B.; Lovely, C. J . Tetrahedron
Lett. 1988, 29, 3725-3728.
pounds 2 were synthesized from â-bromo enals 1 and
the sodium ferrate [(η5-C5H5)(CO)2Fe]Na as previously
described.4,5 Alternatively, compound 4a (Scheme 1,
Table 1) was synthesized from the sodium ferrate [(η5-
C5H5)(CO)2Fe]Na and the corresponding â-bromo-
substituted azadiene 3a in 67% yield (route B). Com-
pound 3a was quantitatively obtained from the corres-
ponding â-bromo enal 1a and benzenesulfonamide (see
the Experimental Section). Purification of the N-sulfonyl
10.1021/om000235j CCC: $19.00 © 2000 American Chemical Society
Publication on Web 08/04/2000

3528 Organometallics, Vol. 19, No. 18, 2000
Amrhein et al.
Ta ble 1. Rea ction s of
â-[(η5-C5H5)(CO)2F e]-su bstitu ted N-su lfon yl
Aza d ien es 4 w ith Gr ign a r d Rea gen ts a n d
Or ga n olith iu m s
Sch em e 3
product (yield, %)
entry reactant method
RM
nBuLi
MeLi
5
6
1
2
3
4
5
6
7
8
9
4a
4a
4a
4b
4b
4b
r a c-4c
r a c-4c
r a c-4c
A
A
B
B
B
A
A
B
C
5a (43) 6a
5b (54) 6b
with organolithiums more byproducts were observed.
After complete consumption of the starting materials
(IR and TLC monitoring) the reaction mixtures were
hydrolyzed with NH4Cl solution or citrate buffer (pH
6) and the crude products purified by flash chromatog-
raphy.
(allyl)MgCl 5c (42) 6c
(allyl)MgCl 5d (37) 6d (41)
nPrMgCl
MeLi
5e (25) 6e (25)
5f (44) 6f (56)
5g (36) 6g (traces)
nBuLi
(allyl)MgCl 5h (19) 6h
(allyl)MgCl 5h (76) 6h
Surprisingly, treatment of 4b with either organolithi-
ums or Grignard reagents gave unprotected dihydro-
pyrrolones 6d -f (ν(CdO) ∼ 1690 cm-1) together with
the expected N-sulfonyl compounds 5d -f as ∼1:1 mix-
tures in 50%-quantitative overall yield. Treatment of
r a c-4c with nBuLi in CH2Cl2 or toluene furnished
traces of impure 6g in addition to 5g according to IR
and NMR spectroscopy (Table 1, entry 7). In all other
cases examined (Table 1, entries 1-3, 8, and 9) products
of type 6 were not isolated or detected by 1H NMR
spectroscopy of the crude product mixtures. The addition
of (allyl)MgCl to the cyclohexene derivative r a c-4c at
room temperature gave the N-sulfonyl γ-lactam 5h in
only 19% yield after flash chromatography. For this case
the influence of higher temperature on the course of the
reaction cascade was studied in more detail. In 1,2-
dichloroethane as solvent, raising the reaction temper-
ature to 50 °C led to complete turnover to the γ-lactam
5h , and the latter was isolated in 76% yield (Table 1,
method C). All attempts to run reactions shown in Table
1 with an excess of organometallic reagents as well as
prolongation of the reaction time led to no significant
increase in yield but gave more impurities.
Sch em e 2
imines 4 was generally accomplished by crystallization
rather than chromatography, because slow decomposi-
tion was observed during silica gel chromatography. The
IR spectra (CH2Cl2) of the iron complexes 4 show two
characteristic ν(CtO) absorptions in the ranges 2020-
2030 and 1970-1980 cm-1. The ν(CdN) stretching
frequencies are generally observed at about 1525-1550
cm-1. The 1H NMR chemical shifts of CHdN range from
δ 8.90 to δ 9.35 in CDCl3.
N-Arenesulfonyl imines are known to undergo 1,2-
addition reactions with various Grignard and organo-
lithium reagents.8,9 In fact, the N-sulfonyl imines 4a -c
reacted with organolithium compounds (method A:
MeLi, nBuLi, THF, 1-1.3 equiv, -78 or 0 °C and then
room temperature) as well as Grignard reagents (method
B: (allyl)MgCl, nPrMgCl, CH2Cl2, room temperature),
furnishing 5-substituted N-sulfonyl dihydropyrrolones
5 and in a few cases 5-substituted N-unprotected
dihydropyrrolones 6 in 40%-quantitative overall yield
(Scheme 2, Table 1). The five-membered annulated
lactam moieties are formed by reaction cascades starting
with the initial 1,2-addition of the C-nucleophile to the
imine functionality followed by a carbonylation and a
subsequent reductive elimination step. The results of
our studies are shown in Table 1. Treatment of com-
pound 4a with either Grignard reagents or organolithi-
ums afforded the γ-lactams 5a -c in 42-54% unopti-
mized yield, in addition to ferrocene, (η5-C5H5)(CO)2Fe
dimer, and undefined byproducts, as indicated by IR and
1H NMR spectroscopy of the crude reaction mixtures.
The characteristic ν(CO) absorption of the γ-lactams 5
is detected at ∼1720-1730 cm-1 in dichloromethane or
THF. Reactions with Grignard reagents carried out at
-78 °C proceeded sluggishly. Generally, in reactions
From the reactions of the iron compounds 4a -c,e
with organometallic reagents 1,2-addition products were
not isolated or identified as byproducts. Only from the
cyclopentene derivative 4d were 1,2-addition products
obtained exclusively, possibly due to steric reasons.5
From (allyl)MgCl and 4d the adduct 7 was isolated in
63% yield after chromatography (Scheme 3). For com-
pound 7 characteristic ν(CdO) stretching frequencies
are observed at 2013 and 1953 cm-1
.
The reaction of compound 4e with (allyl)MgCl was
found to yield the (η3-allyl)iron complex 8a as product
in 84% yield after flash chromatography (Scheme 4). For
the reaction of 4e with nPrMgCl in 1,2-dichloroethane
at room temperature incomplete turnover was observed
after prolonged time (3 days), and 8b was obtained in
only 24% yield. The structure of complex 8a was
elucidated by spectroscopic methods and by X-ray
analysis. In the solid state the intramolecular hydrogen
bond -OH‚‚‚(OdC)- is observed for 8a , as shown by
the structure in Figure 1. Bond lengths and angles are
as expected. Selected data are presented in Figure 1;
the crystallographic data are given in Table 2. An anti
orientation of the metal fragment and the allyl residue
at carbon 5 of the lactam moiety can be concluded from
the single-crystal structure analysis.
(8) Weinreb, S. M. In Topics in Current Chemistry; Metz, P., Ed.;
Springer: Berlin, 1997; Vol. 190, pp 131-184.
(9) (a) Sisko, J .; Weinreb, S. M. J . Org. Chem. 1990, 5, 393-395.
(b) Reetz, M. T.; J aeger, R.; Drewlies, R.; Hu¨bel, M. Angew. Chem.
1991, 103, 76-78; Angew. Chem., Int. Ed. Engl. 1991, 30, 101.
Similarly, the chiral â-[(η5-C5H5)(CO)2Fe]-substituted
N-sulfonyl azadiene 4f, synthesized from 2-sulfamyl-
benzoic acid (-)-menthyl ester and iron compound 2e

(η5-C5H5)(CO)2Fe-Substituted N-Sulfonyl Azadienes
Organometallics, Vol. 19, No. 18, 2000 3529
Sch em e 5
F igu r e 1. Structure of 8a (30% probability ellipsoids).
Selected bond lengths (Å) and angles (deg): Fe-C2 )
2.124(2), Fe-C6 ) 2.030(2), Fe-C20 ) 2.113(3), H27-O7
) 1.814, C2-C6 ) 1.435(3), C2-C3 ) 1.471(3), C6-C20
) 1.408(3), C3-O7 ) 1.225(2); C2-C6-C20 ) 124.7(2),
O7-C3-C2-C6 ) 175.4(2).
for the carbon monoxide ligand and in the range of
1660-1680 cm-1 for the lactam CdO bond.
The formation of the 5-substituted γ-lactams 5 is in
agreement with the mechanistic considerations shown
in Scheme 5. After 1,2-addition of the organometallic
reagent to the imine functionality, leading to intermedi-
ate A, the carbonylation step may proceed either by a
CO insertion followed by a subsequent aminolysis of the
acyl iron intermediate B or by direct attack of the
metalated amide at the carbon monoxide ligand, leading
to the ferrilactam species C prior to reductive elimina-
tion.4,5 By IR monitoring at first the formation of the
metalated amides by 1,2-addition is indicated by the
disappearance of the educt absorptions and by the
appearance of two new ν(CtO) absorptions at lower
wavelength around 2005 and 1955 cm-1. Only for the
reaction of 4c with nBuLi was the appearance and
disappearance of a new absorption at 1853 cm-1 ob-
served subsequently (Table 1, entry 7). For the anionic
ferrilactam C one might expect an absorption for the
carbonyl ligand in this region.10 In all other examples
examined with either Grignard reagents or organolithi-
ums new absorptions at 1950-1990 cm-1 and at 1640-
1660 cm-1 appeared and disappeared, which we at-
tribute to intermediate acyliron complexes B.11
Sch em e 4
Ta ble 2. Cr ysta llogr a p h ic Da ta for 8a
chem formula
fw
cryst syst
space group
Z
C26H23FeNO5S
517.36
orthorhombic
P212121
4
At the current stage of research the formation of the
N-unsubstituted γ-lactams 6 is not completely conclu-
sive. However, during IR monitoring the characteristic
absorptions of the N-unsubstituted γ-lactams 6 at about
1680-1690 cm-1 were not observed. Moreover, rather
harsh acid-catalyzed reductive or electrochemical cleav-
age conditions generally have to be employed to remove
N-arenesulfonyl groups from N-arenesulfonyl carboxa-
mides.12 Iron-mediated redox processes may be involved
in the formation of the unprotected γ-lactams 6.
T, K
a (Å)
b (Å)
298
7.920(2)
20.418(1)
14.807(2)
2394.3(7)
1.4351
0.75
1.5-27.0
5189
4648
328
c (Å)
V (Å3)
D
calcd, g cm-3
µ(Mo KR), mm-1
2θ range, deg
no. of indep rflns
no. of rflns obsd
no. of refined params
S
1.037
The formation of the complexes 8a -c can be rational-
ized according to Scheme 6. Since the formation of the
(η3-allyl)iron-γ-lactam skeletons (ν(CtO) ≈ 1975-1990
cm-1, ν(CdO) ≈ 1660-1680 cm-1) was observed during
R1 (for reflections obsd)
wR2
0.0297
0.0789
0.26
(∆/F)max
(∆/F)min, e Å-3
-0.39
in 53% yield, gave an isomeric mixture (see the Experi-
mental Section) of chromene-ring-opened (η3-allyl)iron
complex 8c upon treatment with (allyl)MgCl (-78 °C,
then room temperature) in 56% overall yield. The IR
spectra of the (η3-allyl)iron complexes 8 in dichloro-
methane display absorptions at about 1975-1990 cm-1
(10) (a) J avaheri, S.; Giering, W. P. Organometallics 1984, 3, 1927.
(b) King, R. B.; Bisnette, M. B. Inorg. Chem. 1966, 5, 293.
(11) Berryhill, S. R.; Rosenblum, M. J . Org. Chem. 1980, 45, 1984-
1986.
(12) (a) Nagashima, H.; Ozaki, N.; Washiyama, M.; Itoh, K. Tetra-
hedron Lett. 1985, 26, 657-660. (b) Casadei, M. A.; Gessner, A.; Inesi,
A.; J ugelt, W.; Moracci, F. M. J . Chem. Soc., Perkin Trans. 1 1992,
2001-2004.

3530 Organometallics, Vol. 19, No. 18, 2000
Amrhein et al.
methyllithium (1.6 M in Et2O) were purchased from Fluka.
Buffer solution was used as indicated (pH 6: 7.86 g of citric
acid monohydrate + 22.28 g of Na2HPO4‚2H2O in 1.0 L of
water). Melting points were determined with a Bu¨chi melting-
point apparatus and are uncorrected. Optical rotations were
Sch em e 6
1
measured on a Perkin-Elmer 241 polarimeter. The H and 13C
NMR spectra were recorded on either a Bruker AC200 or a
Bruker AM400 spectrometer in CDCl3, unless otherwise
stated. Carbon multiplicities were determined by GASPE or
DEPT135; residual protons were used as the internal standard
(CDCl3, δ(1Η) 7.24, δ(13C) 77.0; [D6]DMSO, δ(1Η) 2.49, δ(13C)
39.7). Chemical shifts are given in ppm relative to tetrameth-
ylsilane (TMS), and coupling constants are in Hz. FD, FAB,
and HRMS (EI) mass spectra were recorded on a Finnigan
MAT95. IR spectra were recorded with a Perkin-Elmer 1760X
FTIR spectrometer; NaCl cells were used for IR monitoring.
Thin-layer chromatography (TLC) was performed on Merck
plates (silica gel 60 F254); detection was by UV light (λ ) 254
nm) or by treatment with either a KMnO4 solution (KMnO4
(1.25 g) and Na2CO3 (6.25 g) in water (250 mL)) or a solution
of phosphomolybdic acid (2.5 g), cerium(IV) sulfate (1 g), and
H2SO4 in water (96 mL). Rf values are given for 2:1 petroleum
ether/ethyl acetate. The products were purified by column
chromatography (using the technique developed by Helquist
et al.,14 but without inert gas atmosphere) on Baker silica gel
60 (230-400 mesh) or Florisil (140-200 mesh, supplied by
Aldrich or Fluka). Elemental analyses were carried out by the
Microanalytical Division of the Institute of Organic Chemistry
at the University of Mainz (Mainz, Germany).
Gen er a l P r oced u r es for th e Syn th esis of â-[η5-C5H5-
(CO)2F e]-Su bstitu ted N-Su lfon yl Im in es 4. Rou te A. The
â-[(η5-C5H5)(CO)2Fe]-substituted (Z)-enals 2 were prepared
from the â-bromovinyl aldehydes 1 and [(η5-C5H5)(CO)2Fe]Na
as previously described.4,5 Method A (1.5-8 mmol scale): to a
solution of the (Z)-enal 2 and benzenesulfonamide (1.1 equiv)
in 25 mL of CH2Cl2 was added triethylamine (2.33 equiv) and
TiCl4 (0.6 equiv) at 0 °C. The light-protected mixture was
stirred for 5 min; then the cold bath was removed and stirring
was continued at room temperature. After complete turnover
(IR monitoring) the mixture was added to saturated aqueous
NH4Cl solution. The organic layer was washed with 2 N HCl
(3 × 40 mL). The combined aqueous layer was extracted with
ethyl acetate (3 × 40 mL). The combined organic layer was
washed with brine (50 mL) and dried (MgSO4) and the solvent
removed in vacuo.
Rou te B. According to route A, â-bromo-substituted N-
sulfonyl imines can be prepared from â-bromovinyl aldehydes
1 and benzenesulfonamide as described for the synthesis of
compound 3a . Method B: to a solution of the â-bromo-
substituted N-sulfonyl imine 3 (2.6 mmol) in THF (100 mL)
was added [(η5-C5H5)(CO)2Fe]Na, prepared from [(η5-C5H5)(CO)2-
Fe]2 and sodium amalgam in THF (65 mL) at -78 °C. The
light-protected solution was stirred at -78 °C for 40 min, and
then it was warmed to room temperature over a period of 145
min. The solvent was evaporated and the crude product
purified by column chromatography on Florisil (6:1 to 2:1
petroleum ether/ethyl acetate).
IR monitoring, it seems reasonable to propose the
anionic (π-alkene)iron complex F as an intermediate
being formed from D via E during the reductive
elimination step. Subsequently, an intramolecular nu-
cleophilic substitution reaction would give phenolate
intermediate G prior to hydrolytic workup by attack of
the iron moiety at the neighboring methylene group.
Alternatively, the iron-carbon bond in intermediate D
could break to furnish the iron ketene complex H with
phenoxide anion as the leaving group. Attack of the
metalated amide on the complexed ketene would lead
to intermediate G and, thereby, to the allyl complexes
isolated.13
In conclusion, the 1,2-addition of Grignard reagents
and organolithiums to the imine functionality of â-[(η5-
C5H5)(CO)2Fe]-substituted N-sulfonyl azadienes 4 gen-
erally evolves into reaction cascades leading to 5-sub-
stituted dihydropyrrolones 5, 6, and
8 in 40%-
quantitative overall yield.
Exp er im en ta l Section
All reactions were carried out under an atmosphere of argon
in oven-dried glassware by standard needle/syringe techniques.
THF was dried and distilled from potassium/benzophenone
under argon. CH2Cl2 and 1,2-dichloroethane were distilled
from CaH2 under argon. Solvents were degassed (ultrasound)
before use. CCl4 was distilled over P4O10. Triethylamine was
distilled and stored over KOH. Solvents for chromatography
were of technical quality and were purified as follows: petro-
leum ether (40-60 °C) was distilled from P4O10 and ethyl
acetate from K2CO3. Acetone (p.a., supplied by Riedel-de-Haen)
was used without further purification. Allylmagnesium chlo-
ride (2 M in THF), propylmagnesium chloride (2 M in Et2O),
n-butyllithium (1.6 M in hexane), and TiCl4 (1 M solution in
CH2Cl2) were purchased from Aldrich, sodium amalgam (2%)
was obtained from Lancaster, and {η5-C5H5(CO)2Fe}2 and
9-Br om o-8-[{(p h en ylsu lfon yl)im in o}m eth yl]-6,7-d ih y-
d r o-5H-ben zo[a ]cycloh ep ten e (3a ). According to the gen-
eral procedure (method A) 2 g (7.96 mmol) of the â-bromo enal
1a and 1.25 g (1 equiv) of benzenesulfonamide gave 3.28 g
(quantitative) of crude 3a as a yellow wax. After 2.5 h of
stirring at room temperature workup was carried out by
following the general procedure, except for washing with 2 N
HCl. The aqueous layer was extracted with CH2Cl2 (3 × 40
1
mL); Rf ) 0.65. H NMR (200 MHz): δ 9.30 (s, 1H), 8.00-7.96
(dd, J ) 7.3 Hz, J ) 2.0 Hz, 2H), 7.67-7.50 (m, 4H), 7.38-
7.28 (m, 2H), 7.21-7.17 (m, 1H), 2.62-2.55 (t, J ) 7.3 Hz, 2H),
2.39-2.32 (t, J ) 7.3 Hz, 2H), 2.18-2.04 (quintet, J ) 6.9 Hz,
(13) We thank one of the reviewers for the suggestions made,
especially regarding the formation of the allyl complexes via
complexed ketene intermediate.
a
(14) Kremer, K. A. M.; Helquist, P. Organometallics 1984, 3, 1743.

(η5-C5H5)(CO)2Fe-Substituted N-Sulfonyl Azadienes
Organometallics, Vol. 19, No. 18, 2000 3531
2H). 13C NMR (50.3 MHz): δ 170.4 (CH), 142.4 (Cquat), 140.6
(Cquat), 139.3 (Cquat), 136.7 (Cquat), 133.5 (CH), 130.8 (CH), 130.1
(CH), 129.2 (CH), 128.9 (CH), 128.1 (CH), 126.7 (CH), 33.4
FeNO4S (480.85): C, 59.89; H, 5.62; N, 2.91. Found: C, 59.73;
H, 5.74; N, 2.83.
2-[(η5-Cyclop en t a d ien yl)d ica r b on ylir on ]-1-{[(p h en -
ylsu lfon yl)im in o]m eth yl}cyclop en ten e (4d ). According to
method A 1.23 g (4.52 mmol) of the enal 2d 5 in 50 mL of CH2-
Cl2 gave 1.86 g (quantitative) of 4d as a yellow foam. The
reaction mixture was stirred for 200 min at room temperature.
The combined aqueous layer was extracted with CH2Cl2 (3 ×
(CH2), 31.9 (CH2), 25.4 (CH2); IR (CH2Cl2): ν˜ 1621, 1559 cm-1
.
MS (FD): m/z (%) 394.4 (1.2), 393.4 (6.6), 392.4 (23.3), 391.4
(M+, 100), 389.4 (M+, 98.2). Anal. Calcd for C18H16NO2S‚1/8-
CH2Cl2 (390.1): C, 54.35; H, 4.06; N, 3.50. Found: C, 54.76;
H, 4.42; N, 3.68.
1
9-[(η5-Cyclop en ta d ien yl)d ica r bon ylir on ]-8-{[(p h en yl-
su lfon yl)im in o]m et h yl}-6,7-d ih yd r o-5H -b en zo[a ]cyclo-
h ep ten e (4a ). According to method A treatment of the enal
2a 4 (850 mg, 2.44 mmol) gave 1.19 g (quantitative) of 4a as a
golden yellow foam. Complete turnover was detected after 50
min (IR monitoring). The combined aqueous layer was ex-
tracted with CH2Cl2 (3 × 50 mL).
40 mL). Mp: 161 °C dec. H NMR ([D6]-DMSO, 200 MHz): δ
8.71 (s, 1H), 7.85-7.82 (d, J ) 7.8 Hz, 2H), 7.71-7.58 (m, 3H),
5.13 (s, 5H), 2.89-2.82 (t, J ) 7.3 Hz, 2H), 2.43-2.35 (t, J )
7.3 Hz, 2H), 1.81-1.66 (quintet, J ) 7.3 Hz, 2H). 1H NMR
(200 MHz): δ 8.93 (s, 1H), 7.94-7.90 (d, J ) 7.8 Hz, 2H), 7.55-
7.44 (m, J ) 7.8 Hz, 3H), 4.88 (s, 5H), 2.88-2.81 (t, J ) 7.3
Hz, 2H), 2.57-2.50 (t, J ) 7.3 Hz, 2H), 1.87-1.72 (quintet, J
) 7.3 Hz, 2H). 13C NMR (50.3 MHz): δ 214.0, 210.5, 170.9,
139.9, 132.6, 129.1, 128.9, 127.6, 126.4, 85.7, 56.4, 32.0, 24.2.
IR (CH2Cl2): ν˜ 2027, 1976, 1536 cm-1. IR (KBr): ν˜ 3117, 2967,
2021, 1969, 1529, 1447, 1347, 1318, 1304, 1290, 1156, 1088,
813, 743, 589, 555 cm-1. MS (FD): m/z (%) 411 (M+, 2.33%),
382.9 (M+ - CO, 100%). Anal. Calcd for C19H17FeNO4S‚1/8CH2-
Cl2 (410.85): C, 54.04; H, 4.27; N, 3.32. Found: C, 53.93; H,
4.26; N 3.29. Recrystallization from CH2Cl2/petroleum ether
furnished brown-yellow crystals.
By following method B, treatment of the â-bromo-substi-
tuted N-sulfonyl imine 3a (1 g, 2.56 mmol) with [(η5-C5H5)(CO)2-
Fe]Na, prepared from [{η5-C5H5(CO)2Fe}2] (476 mg, 1.35 mmol)
and sodium amalgam (4.12 g), afforded 832 mg (67%) of 4a as
a yellow solid.
1
Mp: 93-94 °C (dec). Rf ) 0.52. H NMR (200 MHz): δ 9.19
(s, 1H), 7.99-7.96 (d, J ) 6.3 Hz, 2H), 7.59-7.49 (m, 3H),
7.24-7.21 (m, 1H), 7.12-6.98 (m, 3H), 5.09 (s, 5H), 2.92-2.86
(m, 1H), 2.41-2.32 (m, 1H), 2.16-2.06 (m, 1H), 1.85-1.64 (m,
4-[(η5-Cyclop en ta d ien yl)d ica r bon ylir on ]-3-{[(p h en yl-
su lfon yl)im in o]m eth yl}-(2H)-ch r om en e (4e). According to
method A 500 mg (1.49 mmol) of the enal 2e4 gave 708 mg
(quantitative) of 4e as a yellow amorphous solid. Complete
turnover was detected after 100 min (IR monitoring). The
combined aqueous layer was extracted with CH2Cl2 (3 × 50
3H). 13C NMR (50.3 MHz): δ 214.6 (Cquat, CO), 212.5 (Cquat
,
CO), 200.3 (Cquat), 175.6 (CH), 155.7 (Cquat), 149.2 (Cquat), 139.7
(Cquat), 133.6 (Cquat), 132.8 (CH), 129.1 (CH), 128.6 (CH), 128.1
(CH), 127.7 (CH), 127.6 (CH), 126.9 (CH), 126.4 (CH), 126.1
(CH), 86.2 (CH), 31.9 (CH2), 31.7 (CH2), 26.6 (CH2). IR (CH2-
Cl2): ν˜ 2027, 1977, 1529 cm-1. MS (FD): m/z (%) 459.2 (27.9,
M+- CO), 339.0 (46.7), 156.7 (100, PhSO2NH2). Anal. Calcd
for C25H21FeNO4S (486.85)‚0.5CH2Cl2: C, 57.81; H, 4.16; N,
2.64. Found: C, 57.46; H, 4.06; N, 2.65.
2-[(η5-Cyclop en ta d ien yl)d ica r bon ylir on ]-1-{[(p h en yl-
su lfon yl)im in o]m eth yl}-3,4-d ih yd r on a p h th a len e (4b). Ac-
cording to method A 1.385 g (4.15 mmol) of the enal 2b4 gave
1.96 g (quantitative) of 4b as a yellow-brown amorphous solid.
The reaction mixture was stirred for 16.5 h at room temper-
ature before workup. Rf ) 0.42. 1H NMR (200 MHz): δ 9.34 (s,
1H), 8.01-7.97 (d, J ) 8.3 Hz, 2H), 7.87-7.84 (d, J ) 7.8 Hz,
1H), 7.58-7.46 (m, 3H), 7.19-7.04 (m, 3H), 5.05 (s, 5H), 3.06-
2.99 (t, J ) 6.8 Hz, 2H), 2.57-2.50 (t, J ) 6.8 Hz, 2H). 13C
NMR (100.6 MHz): δ 215.3 (Cquat), 213.5 (Cquat, CO), 175.9
(CH), 144.0 (Cquat), 139.9 (Cquat), 135.9 (Cquat), 132.8 (CH), 132.1
(Cquat), 129.0 (CH), 127.6 (CH), 126.4 (CH), 126.4 (CH), 126.2
(CH), 125.0, (CH), 86.5 (CH), 51.4 (CH2), 29.4 (CH2). IR (CH2-
Cl2): ν˜ 2027, 1977, 1548 cm-1. IR (KBr): ν˜ 3054, 2986, 2019,
1968, 1535, 1446, 1422, 1346, 1164, 1088, 813, 800 cm-1. MS
(FD): m/z (%) 473.0 (M+, 2.0), 447 (8.5), 446.0 (19.9), 445.0
(M+- CO, 100), 443.0 (2.7), 389.0 (3.6), 324.9 (9.1).
1
mL). Mp: 167 °C (dec). Rf ) 0.39. H NMR (400 MHz): δ 9.19
(s, 1H), 7.96-7.94 (dd, J ) 7.6 Hz, J ) 1.2 Hz, 2H), 7.64-7.62
(dd, J ) 7.9 Hz, J ) 1.2 Hz, 1H), 7.58-7.56 (d, J ) 7.3 Hz,
1H), 7.53-7.49 (t, J ) 7.5 Hz, 2H), 7.22-7.18 (m, 1H), 7.05-
6.95 (m, 1H), 6.86-6.84 (d, J ) 7.9 Hz, 1H), 5.11 (s, 5H), 4.75-
4.3 (br s, 2H). 1H NMR ([D6]-DMSO, 200 MHz): δ 8.90 (s, 1H),
7.93-7.89 (d, J ) 6.8 Hz, 2H), 7.83-7.71 (m, J ) 6.8 Hz, 3H),
7.35-7.23 (m, J ) 7.3 Hz, 2H), 7.10-7.03 (m, 1H), 6.87-6.83
(d, J ) 7.8 Hz, 1H), 5.33 (s, 5H), 5.0-4.65 (br s, 1H), 4.5-4.2
(br s, 1H). 13C NMR (100.6 MHz): δ 213.6, 189.3, 173.0, 153.8,
141.7, 139.5, 136.1, 135.0, 132.9, 131.6, 129.0, 127.7, 121.2,
116.5, 86.6, 65.8. 13C NMR ([D6]-DMSO, 50.3 MHz): δ 213.6,
189.7, 173.0, 153.7, 141.7, 139.4, 136.1, 135.0, 133.0, 131.6,
129.1, 127.6, 121.2, 116.5, 86.6, 65.7. IR (KBr): ν˜ 3112, 3070,
2854, 2030, 2021, 1970, 1521, 1494, 1322, 1302, 1285, 1158,
1085, 816, 734, 607, 585, 560 cm-1. IR (CH2Cl2): ν˜ 2030, 1980,
1526 cm-1. MS (FAB): m/z (%) 476.0 (M+ + H+, 19.4), 418.9
(M+ - 2CO, 11.4), 306.9 (31.9), 153.6 (100, PhSO2N). Anal.
Calcd for C23H17FeNO5S‚0.25 CH2Cl2 (475.02): C, 56.27; H,
3.38; N, 2.75. Calcd: C, 56.25; H, 3.53; N, 2.82. Recrystalli-
zation from CHCl3/petroleum ether furnished yellow crystals.
4-[(η5-Cyclop en ta d ien yl)d ica r bon ylir on ]-3-{[(o-ben zo-
ic a cid (-)-m en t h yl est er )su lfon yl]im in om et h yl}-(2H )-
ch r om en e (4f). According to method A 638 mg (1.90 mmol)
of the enal 2e4 and 627 mg (1.86 mmol) of 2-sulfamylbenzoic
acid (-)-menthyl ester gave 789 mg (65%) of crude 4f as a
golden yellow foam. After 5 h of stirring at room temperature
another 0.4 equiv of TiCl4 and then 0.21 mL (1.86 mmol, 2
equiv) of orthoformic acid trimethyl ester were added to the
reaction mixture (IR monitoring) to complete turnover. The
product was purified by flash chromatography with petroleum
ether/ethyl acetate (4:1 to ethyl acetate) to yield 644 mg (53%)
of 4f. Mp: 175 °C dec. Recrystallization from CH2Cl2/petroleum
ether furnished brown-yellow crystals. RD20 ) -38.9° (c ) 0.1;
2-[(η5-Cyclop en ta d ien yl)d ica r bon ylir on ]-5-ter t-bu tyl-
1-[(p h en ylsu lfon yl)im in om eth yl]-1-cycloh exen e (r a c-4c).
According to method A 1.93 g (5.65 mmol) of the enal 2c5 in
50 mL of CH2Cl2 gave 2.63 g (97%) of 4c as a yellow amorphous
solid. Complete turnover was detected after 5 h (IR monitor-
ing). The combined aqueous layer was extracted with CH2Cl2
1
(3 × 50 mL). Mp: 105 °C dec. Rf ) 0.55. H NMR (400 MHz):
δ 9.00 (s, 1H), 7.95-7.93 (d, J ) 7.33 Hz, 2H), 7.57-7.54 (m,
1H), 7.51-7.47 (m, 2H), 4.88 (s, 5H), 3.07-3.02 (d, J ) 19.6
Hz, 1H), 2.83-2.74 (m, 1H), 2.53-2.49 (d, J ) 15.8 Hz, 1H),
2.03-1.97 (m, 1H), 1.63-1.59 (m, 1H), 1.23-1.11 (m, 2H), 0.82
(s, 9H). 13C NMR (50.3 MHz, mixture of isomers or conformers,
ratio: ∼6:1, the asterisk denotes minor): δ 214.6, 214.4, 204.4,
177.7, 144.5, 139.8, 132.8*, 132.7, 129.2*, 129.0, 127.7, 126.5*,
86.4, 54.4, 44.0, 32.4, 30.5, 27.7, 27.2. IR (CH2Cl2): ν˜ 2022,
1969, 1525 cm-1. IR (KBr): ν˜ 2961, 2868, 2017, 1964, 1755,
1720, 1636, 1525, 1478, 1448, 1365, 1331, 1307, 1237, 1155,
1089, 811, 593 cm-1. MS (FD): m/z (%) 937.6 (1.7), 936.9 (3.9),
935.7 (25.7), 934.7 (2 M+ - CO, 59.9), 455.1 (1.8), 454.1 (28.5),
1
CH2Cl2). Rf ) 0.5. H NMR (400 MHz): δ 9.02 (s, 1H), 8.26-
8.24 (m, 1H), 7.64-7.62 (m, 3H), 7.59-7.58 (m, 1H), 7.21-
7.17 (dt, J ) 7.3 Hz, J ) 1.2 Hz, 1H), 7.01-6.97 (t, J ) 7.3
Hz, 1H), 6.86-6.84 (d, J ) 8.2 Hz, 1H), 5.15 (s, 5H), 4.89-
4.83 (dt, J ) 11.2 Hz, J ) 4.1 Hz, 1H), 4.70-4.30 (br s, 2H),
2.30-2.20 (m, 1H), 2.08-2.04 (m, 1H), 1.72-1.65 (m, 1H),
1.54-1.48 (m, 1H), 1.46-1.38 (m, 1H), 1.19-1.00 (m, 2H),
453.1 (M+- CO, 100), 451.1 (1.5). Anal. Calcd for C24H27
-

3532 Organometallics, Vol. 19, No. 18, 2000
Amrhein et al.
0.95-0.88 (m, 8H), 0.82-0.80 (d, J ) 7.0 Hz, 3H). 13C NMR
(50.3 MHz): δ 213.4 (Cquat, CO), 188.6 (Cquat), 173.2 (CH), 166.6
(Cquat), 153.8 (Cquat), 142.1 (Cquat), 137.5 (Cquat), 136.3 (Cquat),
135.0 (CH), 133.4 (Cquat), 132.8 (CH), 131.3 (CH), 130.9 (CH),
128.9 (CH), 122.0 (CH), 116.5 (CH), 86.6 (CH), 76.2 (CH), 65.9
(CH2), 47.0 (CH), 40.5 (CH2), 34.2 (CH2), 31.6 (CH), 26.2 (CH),
23.3 (CH2), 22.0 (CH3), 20.9 (CH3), 16.1 (CH3). IR (CH2Cl2): ν˜
2030, 1980, 1723, 1524 cm-1. IR (KBr): ν˜ 2956, 2928, 2869,
MHz): δ 168.5 (Cquat, CdO), 160.6 (Cquat), 142.5 (Cquat), 139.2
(Cquat), 133.7 (CH), 129.2 (Cquat), 129.2 (Cquat), 129.1 (CH), 128.9
(CH), 128.8 (CH), 128.4 (CH), 128.0 (CH), 126.2 (CH), 63.9
(CH), 33.9 (CH2), 30.0 (CH2), 28.9 (CH2), 28.7 (CH2), 23.4 (CH2),
22.4 (CH2), 13.9 (CH3). IR (CH2Cl2): ν˜ 1718 cm-1. MS (FD):
m/z (%) 396.1 (17), 395.1 (M+, 100); C23H25NO3S. HR-MS (EI):
m/z found 395.1541, calcd 395.1549.
5′-Meth yl-N-(p h en ylsu lfon yl)-4,5,6-tr ih yd r o-3H-ben zo-
[3,4]cycloh epta[1,2-c]pyr r ol-1′-on e (5b). According to method
A treatment of the imine 4a (564 mg, 1.16 mmol) with MeLi
gave 222 mg (54%) of 5b as a light yellow solid. The reaction
mixture was stirred for 23 h at room temperature before
2025, 1975, 1723, 1523 cm-1. MS (FAB): m/z (%) 658.6 (M+
+
H+, 77.3), 601.5 (M+ - 2CO, 55.9), 277.8 (100). Anal. Calcd
for C34H35FeNO7S (656.85): C, 62.11; H, 5.33; N, 2.13; S, 4.87;
Found: C, 61.84; H, 5.79; N, 1.86; S, 4.85.
1
2-Su lfa m ylben zoic a cid (-)-m en th yl ester was prepared
according to the following procedure: a solution of 15.16 g (76
mmol) o-sulfamidobenzoic acid, 17.9 g (1.5 equiv, 114 mmol)
of (-)-menthol and 2 g (11 mmol) of p-toluenesulfonic acid in
400 mL of tetrachloromethane was refluxed (Dean and Stark
separator) for 84 h.15 The collected water was removed
occasionally. After this time 5 drops of H2SO4 was added to
the suspension and the mixture was refluxed for another 24
h. The solvent was removed and the product mixture separated
by flash chromatography (silica gel, 6:1 to 2:1 petroleum ether/
ethyl acetate) to yield 2.37 g (9.5%) of a colorless solid. Mp:
89-90 °C. Rf ) 0.56. RD20 ) -47.3° (c ) 0.1; CH2Cl2). 1H NMR
(200 MHz): δ 8.13-8.07 (m, 1H), 7.79-7.73 (m, 1H), 7.65-
7.56 (m, 2H), 5.74 (br s, 2H, NH2), 5.04-4.91 (dt, J ) 10.7 Hz,
J ) 4.4 Hz, 1H), 2.19-2.11 (m, 1H), 2.07-1.91 (m, 1H), 1.76-
1.69 (m, 2H), 1.60-1.47 (m, 2H), 1.18-1.00 (m, 2H), 0.94-
0.89 (m, 7H), 0.83-0.79 (d, J ) 6.9 Hz, 3H). 13C NMR (50.3
MHz): δ 167.4 (Cquat, CdO), 141.4 (Cquat), 132.3 (CH), 131.7
(CH), 131.0 (Cquat), 130.3 (CH), 128.3 (CH), 77.0 (CH), 47.1
(CH), 40.5 (CH2), 34.2 (CH2), 31.5 (CH), 26.3 (CH), 23.3 (CH2),
22.0 (CH3), 20.8 (CH3), 16.1 (CH3). IR (KBr): ν˜ 3365, 3256,
3087, 2959, 2946, 2925, 1718, 1458, 1356, 1299, 1273, 1151,
1140, 1121, 1063, 1056, 952, 758, 732, 717 cm-1. Anal. Calcd
for C17H25NO4S (337.9): C, 60.37; H, 7.40; N, 4.14. Found: C,
60.19; H, 7.30; N, 4.09.
Gen er a l P r oced u r e for t h e Syn t h esis of t h e r,â-
Un sa tu r a ted γ-La cta m s 5, 6, a n d 8. Meth od A: Ad d ition
of Or ga n olith iu m Rea gen ts. To a light-protected solution
of the N-sulfonyl imine 4 in 15-20 mL of THF was added 1.1
equiv of the organolithium reagent at -78 or 0 °C. After
removal of the cold bath the reaction mixture was stirred at
room temperature. After complete turnover (IR monitoring),
the reaction mixture was worked up according to method B
unless otherwise noted.
Meth od B: Ad d ition of Gr ign a r d Rea gen ts. To a light-
protected solution of the N-sulfonyl imine 4 in 10-25 mL of
CH2Cl2 was added 2.05 equiv of the Grignard reagent at room
temperature. After complete turnover (IR monitoring), the
mixture was added to an aqueous saturated NH4Cl solution
with stirring. After phase separation, the aqueous layer was
extracted with ethyl acetate (3 × 40 mL). The combined
organic layer was dried (MgSO4) and the solvent evaporated.
The crude product was purified by flash chromatography (silica
gel, 15:1 to 2:1 petroleum ether/ethyl acetate, then ethyl
acetate unless otherwise noted).
workup. Mp: 127-129 °C. Rf ) 0.58. H NMR (400 MHz): δ
8.13-8.11 (dd, J ) 7.3 Hz J ) 1.5 Hz, 2H), 7.89-7.87 (dd, J
) 7.8 Hz, J ) 1.2 Hz, 1H), 7.61-7.57 (t, J ) 7.3 Hz, 1H), 7.53-
7.49 (t, J ) 7.3 Hz, 2H), 7.24-7.16 (m, 2H), 7.11-7.10 (d, J )
7.1 Hz, 1H), 4.72-4.67 (q, J ) 6.8 Hz, 1H), 2.67-2.53 (m, 3H),
2.50-2.42 (m, 1H), 2.19-2.02 (m, 2H), 1.67-1.65 (d, J ) 6.5
Hz, 3H). 13C NMR (50.3 MHz): δ 167.9 (Cquat, CO), 162.7 (Cquat),
142.3 (Cquat), 139.2 (Cquat), 133.7 (CH), 129.1 (Cquat), 128.9 (CH),
128.8 (CH), 128.3 (CH), 128.1 (CH), 126.1 (CH), 60.1(CH), 33.7
(CH2), 29.1 (CH2), 28.5 (CH2), 19.5 (CH3); one quaternary signal
and one tertiary signal in the aromatic region are overlapped
by the adjacent tertiary signals. IR (KBr): ν˜ 3018, 2999, 2943,
2869, 1707, 1664, 1449, 1356, 1340, 1330, 1184, 1169, 1157,
1091 cm-1. IR (CH2Cl2): ν˜ 1721 cm-1. MS (FD): m/z (%) 356.3
(0.7), 355.3 (3.2), 354.3 (14), 353.2 (M+, 100); C20H19NO3S
(353.0). HR-MS (EI): m/z found 353.1099, calcd 353.1086.
5′-Allyl-N-(p h en ylsu lfon yl)-4,5,6-t r ih yd r o-3H -b en zo-
[3,4]cycloh epta[1,2-c]pyr r ol-1′-on e (5c). According to method
B treatment of the imine 4a (256 mg, 0.53 mmol) with
allylmagnesium chloride gave 83 mg (42%) of 5c as a yellow
oil. The solution was stirred for 22.5 h at room temperature
before workup. Rf ) 0.64. 1H NMR (400 MHz): δ 8.16-8.14
(d, J ) 7.4 Hz, 2H), 7.91-7.89 (dd, J ) 7.3 Hz, J ) 1.5 Hz,
1H), 7.62-7.59 (t, J ) 7.3 Hz, 1H), 7.54-7.50 (t, J ) 7.3 Hz,
2H), 7.23-7.16 (m, 2H), 7.12-7.10 (d, J ) 7.0 Hz, 1H), 5.34-
5.24 (m, J ) 15.8 Hz, J ) 9.1 Hz, J ) 7.6 Hz, 1H, CHdCH2),
5.05-5.01 (dd, J ) 15.8 Hz, J ) 1.2 Hz, 1H), 4.98-4.95 (d, J
) 10.3 Hz, 1H), 4.83-4.81 (dd, J ) 7.3 Hz, J ) 0.9 Hz, 1H),
3.30-3.23 (m, 1H), 2.68-2.42 (m, 5H), 2.12-2.06 (quintet, J
) 7.0 Hz, 2H). 13C NMR (50.3 MHz): δ 168.4 (Cquat, CO), 160.3
(Cquat), 142.6 (Cquat), 139.1 (Cquat), 133.8 (CH), 129.6 (CH), 129.2
(Cquat), 129.0 (CH), 129.0 (CH), 128.8 (CH), 128.4 (CH), 128.2
(CH), 126.2 (CH), 120.0 (CH2), 63.3 (CH), 34.9 (CH2), 33.8
(CH2), 28.9 (CH2), 28.8 (CH2); one quaternary signal of the
aromatic region is overlapped by the adjacent tertiary signal.
IR (KBr): ν˜ 3067, 2961, 2932, 1718 cm-1. IR (CH2Cl2): ν˜ 1721
cm-1. MS (FD): m/z (%) 381.0 (6.3), 379.9 (22.8), 378.9 (M+,
100); C22H21NO3S (379.1). HR-MS (EI): m/z found 379.1242,
found 379.1242.
Rea ction of 4b w ith (a llyl)MgCl. According to method B
561 mg (1.19 mmol) of the imine 4b gave 161 mg (37%) of 5d
and 111 mg (41%) of 6d as yellow oils. The solution was stirred
for 22 h at room temperature before workup.
1-Allyl-1,2,3,4,5-p en ta h yd r o-N-(p h en ylsu lfon yl)ben zo-
[e]isoin d ol-3-on e (5d ). Rf ) 0.74. 1H NMR (200 MHz): δ
8.16-8.13 (d, J ) 6.8 Hz, 2H), 7.65-7.46 (m, 3H), 7.33-7.14
(m, 4H), 5.35-5.30 (dd, J ) 6.4 Hz, J ) 2.9 Hz, 1H), 5.23-
5.06 (m, J ) 7.3 Hz, J ) 9.8 Hz, J ) 14.4 Hz, 1H, CHdCH2),
4.84-4.79 (dd, J ) 10.3 Hz, J ) 1.2 Hz, 1H), 4.70-4.61 (dd, J
) 6.6 Hz, J ) 1.2 Hz, 1H), 3.30-3.17 (m, 1H), 2.87-2.51 (m,
4H), 2.37-2.21 (m, 1H). 13C NMR (50.3 MHz): δ 168.5, 153.5,
139.9, 138.2, 133.8, 130.8, 130.2, 129.2, 129.0, 129.0, 128.8,
128.1, 127.1, 124.2, 120.2, 61.0, 35.4, 27.9, 18.0. IR (CH2Cl2):
ν˜ 1719 cm-1. MS (FD): m/z (%) 368.0 (1.2), 367.0 (7.0), 366.0
(24.2), 365.0 (M+, 100), 269.9 (2.4); C21H19NO3S (365.0). HR-
MS (EI): m/z found 365.1070, calcd 365.1081.
5′-n -Bu tyl-N-(p h en ylsu lfon yl)-4,5,6-tr ih yd r o-3H-ben zo-
[3,4]cycloh epta[1,2-c]pyr r ol-1′-on e (5a). According to method
A treatment of the imine 4a (500 mg, 1.03 mmol) with nBuLi
gave 173 mg (43%) of 5a as a yellow oil. The addition of nBuLi
was carried out at -78 °C. Stirring was continued at -78 °C
for 20 h and at room temperature for 23 h. Rf ) 0.76. 1H NMR
(200 MHz): δ 8.17-8.12 (dd, J ) 7.6 Hz, J ) 1.5 Hz, 2H), 7.97-
7.93 (dd, J ) 7.3 Hz, J ) 2.0 Hz, 1H), 7.65-7.46 (m, 3H), 7.28-
7.08 (m, 3H), 4.82-4.79 (dd, J ) 7.3 Hz, J ) 2.9 Hz, 1H), 2.68-
2.60 (q, J ) 4.9 Hz, 2H), 2.52-2.35 (t, J ) 7.3 Hz, 3H), 2.15-
2.06 (m, 2H), 1.99-1.77 (m, 2H), 1.23-1.07 (m, 2H), 0.87-
0.77 (m, 1H), 0.75-0.68 (t, J ) 7.3 Hz, 3H). 13C NMR (50.3
1-Allyl-1,2,3,4,5-pen tah ydr oben zo[e]isoin dol-3-on e (6d).
Rf ) 0.1. 1H NMR (200 MHz): δ 7.26-7.21 (m, 3H), 7.18-7.13
(m, 1H), 6.48 (br s, 1H, NH), 5.88-5.67 (m, J ) 7.4 Hz, J )
(15) Loev, B.; Kormendy, M. J . Org. Chem. 1962, 27, 1703-1709.

(η5-C5H5)(CO)2Fe-Substituted N-Sulfonyl Azadienes
Organometallics, Vol. 19, No. 18, 2000 3533
10.2 Hz, J ) 15.1 Hz, 1H, CHdCH2), 5.15 (s, 1H), 5.10-5.07
(d, J ) 5.9 Hz, 1H), 4.57-4.53 (m, 1H), 2.95-2.88 (m, 2H),
2.78-2.72 (m, 1H), 2.69-2.61 (m, 1H), 2.43-2.33 (m, 1H),
(%) 198.9 (M+, 100), 196.9 (11.4); C13H13NO (199.0). HR-MS
(EI): m/z found 199.0999, calcd 199.0997.
3-n -Bu t yl-5-ter t-b u t yl-N-(p h en ylsu lfon yl)-4,5,6,7-t et -
r ah ydr o-1(3H)-isoben zopyr r olon e (5g). According to method
A treatment of the imine r a c-4c (880 mg, 1.83 mmol) with
nBuLi gave 252 mg (35.5%, isomeric mixture ∼2.5:1 (13C
NMR)) of 5g as a yellow oil. The reaction mixture was stirred
at 0 °C (90 min) and at room temperature (2 h). The reaction
mixture was added to a buffer solution (pH 6, 80 mL), and
the aqueous layer was extracted with ethyl acetate (3 × 40
2.29-2.10 (m, 1H). 13C NMR (50.3 MHz): δ 173.0 (Cquat
,
CdO), 152.0 (Cquat), 137.6 (Cquat), 133.0 (CH), 132.0 (Cquat),
129.4 (CH), 129.3 (Cquat), 128.6 (CH), 126.8 (CH), 123.4 (CH),
119.0 (CH2), 55.6 (CH), 38.0 (CH2), 28.3 (CH2), 18.3 (CH2). IR
(CH2Cl2): ν˜ 1690 cm-1. MS (FD): m/z (%) 226.9 (0.5), 225.9
(16.1), 224.8 (M+, 100), 223.8 (1.0), 222.8 (2.9); C15H15NO
(225.0). HR-MS (EI): m/z found 225.1142, calcd 225.1150.
1
mL). Rf ) 0.78. H NMR (200 MHz): δ 8.09-8.05 (dd, J ) 8.3
Rea ction of 4b w ith n P r MgCl. According to method B
560 mg (1.18 mmol) of the imine 4b gave 108 mg (25%) of 5e
and 66 mg (25%) of 6e as yellow oils. After having been stirred
for 20 h 40 min at room temperature another 0.6 equiv of the
Grignard reagent was added due to incomplete turnover (IR
monitoring). Stirring was continued, and after 8.5 h the
reaction mixture was added to a buffer solution (pH 6, 60 mL)
with stirring. The aqueous layer was extracted with CH2Cl2
(3 × 40 mL).
Hz, J ) 1.5 Hz, 2H), 7.62-7.44 (m, 3H), 4.70 (m, 1H), 2.37-
2.11 (m, 3H), 1.96-1.71 (m, 4H), 1.69-1.67 (d, J ) 2.9 Hz,
1H), 1.16-0.94 (m, 3H), 0.88 (s, 9H), 0.77-0.56 (m, 5H). 13C
NMR (50.3 MHz, the asterisk denotes minor): δ 169.3 (Cquat
,
CdO), 159.6*, 159.4 (Cquat), 139.5 (Cquat), 133.6 (CH), 130.9,
130.7* (Cquat), 128.9 (CH), 127.8 (CH), 64.6*, 64.1 (CH), 44.3,
43.9* (CH), 32.3 (Cquat), 29.7, 29.2* (CH2), 27.2 (CH3), 25.7*,
24.9 (CH2), 23.5 (CH2), 23.2 (CH2), 22.3 (CH2), 20.9 (CH2), 13.8
(CH3). IR (CH2Cl2): ν˜ 1720 cm-1. MS (FD): m/z (%) 392.1 (3.1),
391.1 (8.0), 390.1 (M+ + H+, 41), 389.1 (M+, 3.9), 388.1 (3.8),
335.0 (0.8), 334.0 (5.4), 333.0 (23.4), 332.0 (M+ - C4H9, 100);
1,2,3,4,5-P en t a h yd r o-N-(p h en ylsu lfon yl)-1-n -p r op yl-
ben zo[e]isoin d ol-3-on e (5e). Rf ) 0.67. 1H NMR (400 MHz):
δ 8.15-8.11 (dd, J ) 7.8 Hz, J ) 2.0 Hz, 2H), 7.61-7.48 (m,
3H), 7.32-7.20 (m, 4H), 5.34-5.32 (dd, J ) 3.9 Hz, J ) 1.0
Hz, 1H), 2.90-2.80 (m, 2H), 2.67-2.56 (m, 1H), 2.49-2.23 (m,
2H), 2.03-1.84 (m, 1H), 0.85-0.81 (m, 1H), 0.78-0.68 (m, 1H),
C
22H31NO3S (389).
3-Allyl-5-ter t-bu tyl-N-(p h en ylsu lfon yl)-4,5,6,7-tetr a h y-
d r o-1(3H)isoben zop yr r olon e (5h ). According to method C
treatment of the imine r a c-4c (500 mg, 1.04 mmol) gave 295
mg (76%, isomeric mixture ∼2:1 (13C NMR)) of 5h as a yellow
oil. The reaction was carried out in 1,2-dichloroethane (13 mL),
and the reaction mixture was heated to 50 °C for 6 h before
stirring was continued for 17 h at room temperature. Rf ) 0.66.
1H NMR (200 MHz): δ 8.09-8.04 (m, 2H), 7.63-7.45 (m, 3H),
5.36-5.09 (m, J ) 7.3 Hz, J ) 10.3 Hz, J ) 14.2 Hz, 1H,
CHdCH2), 5.03-4.88 (m, 2H), 4.67-4.65 (m, 1H), 3.17-3.00
(m, 1H), 2.59-2.49 (m, 1H), 2.34-2.13 (m, 2H), 2.01-1.83 (m,
2H), 1.38-0.94 (m, 3H), 0.86 (s, 9H). 13C NMR (50.3 MHz, the
asterisk denotes minor): δ 169.2 (Cquat, CdO), 159.3, 159.1*
(Cquat), 139.3 (Cquat), 133.7 (CH), 131.3*, 131.0 (Cquat), 129.9
(CH), 128.9 (CH), 128.0 (CH), 119.6, 119.5* (CH2), 63.8, 63.3*
(CH), 44.1*, 44.0 (CH), 34.7*, 34.3 (CH2), 27.2 (CH3), 26.0
(CH2), 25.2 (CH2), 23.1 (CH2), 20.9 (CH2). IR (CH2Cl2): ν˜ 1723
cm-1. MS (FD): m/z (%) 377.2 (1.3), 375.1 (8.9), 374.1 (M+,
54.2), 373.1 (25.1), 372.1 (0.8), 319.0 (1.0), 318.0 (2.7), 317.0
(22.0), 316.0 (M+ - C4H9, 100), 314.9 (1.3); C21H27NO3S (374.0).
HR-MS (EI): m/z found 374.1774, calcd 374.1783.
0.65-0.60 (m, 3H). 13C NMR (50.3 MHz): δ 168.6 (Cquat
,
CdO), 153.9 (Cquat), 139.4 (Cquat), 138.1 (Cquat), 133.7 (CH),
130.7 (CH), 129.8 (Cquat), 129.0 (CH), 128.8 (CH), 128.1 (Cquat),
127.9 (CH), 127.1 (CH), 124.2 (CH), 61.7 (CH), 33.0 (CH2), 27.9
(CH2), 18.0 (CH2), 14.7 (CH2), 13.5 (CH3). IR (CH2Cl2): ν˜ 1718
cm-1. MS (FD): m/z (%) 370.1 (1.0), 369.1 (13.6), 368.1 (18.5),
367.1 (M+, 100), 366.1 (0.8); C21H21NSO3 (367).
1,2,3,4,5-P e n t a h yd r o-1-n -p r op ylb e n zo[e]isoin d ol-3-
on e (6e). Rf ) 0.11. 1H NMR (200 MHz): δ 7.25-7.11 (m, 4H),
6.47 (br s, 1H), 4.56 (m, 1H), 2.92-2.87 (m, 2H) 2.71-2.62 (m,
1H), 2.47-2.34 (m, 1H), 1.93-1.88 (m, 1H), 1.55-1.29 (m, 3H),
0.94-0.82 (m, 3H). 13C NMR (50.3 MHz): δ 173.3, 152.7, 137.6,
131.5, 129.6, 129.3, 128.5, 126.7, 123.5, 56.2, 35.7, 28.3, 18.7,
18.3, 13.9. IR (CH2Cl2): ν˜ 1687 cm-1. MS (FD): m/z (%) 228.0
(21.1), 227.0 (M+, 100); C15H17NO (227.0). HR-MS (EI): m/z
found 227.1306, calcd 227.1310.
Rea ction of 4b w ith MeLi. According to method A 500
mg (1.057 mmol) of the imine 4b gave 159 mg (44%) of 5f and
119 mg (56%) of 6f as yellow oils. The mixture was stirred for
19.5 h at room temperature before the reaction mixture was
added to a buffer solution (pH 6, 60 mL) and worked up as
described before for 5d and 6d . The crude product was purified
by flash chromatography on Florisil (20:1 petroleum ether/
ethyl acetate (1% NEt3) to ethyl acetate and then acetone).
1-Allyl-1-(a m in om et h yl)-2-[cyclop en t a d ien yld ica r b -
on ylir on ]-N-p h en ylsu lfon ylcyclop en ten e 7. According to
method B treatment of the imine 4d (280 mg, 0.68 mmol) with
1.5 equiv of (allyl)MgCl gave 194 mg (63%) of 7 as a yellow
oil, which solidified on standing at 4 °C. The reaction mixture
was stirred for 1 h (IR monitoring). The combined aqueous
layer was extracted with CH2Cl2 (3 × 40 mL). Purification of
the crude product was performed by column chromatography.
Rf ) 0.61. 1H NMR (200 MHz): δ 7.87-7.84 (d, J ) 6.3 Hz,
2H), 7.54-7.47 (m, 3H), 5.75-5.54 (m, J ) 6.8 Hz, J ) 9.8
Hz, 1H, CHdCH2), 5.02-5.01 (d, J ) 2.9 Hz, 1H), 4.95 (s, 1H),
4.81 (s, 5H), 4.51-4.48 (d, J ) 6.3 Hz, 1H), 4.39-4.29 (m, 1H),
1-Meth yl-1,2,3,4,5-p en ta h yd r o-N-(p h en ylsu lfon yl)ben -
zo[e]isoin d ol-3-on e (5f). Rf ) 0.52. 1H NMR (200 MHz): δ
8.14-8.10 (dd, J ) 7.8 Hz, J ) 1.5 Hz, 2H), 7.61-7.48 (m,
3H), 7.35-7.15 (m, 4H), 5.22-5.16 (m, 1H), 2.91-2.83 (dd, J
) 5.9 Hz, J ) 4.9 Hz, 2H), 2.65-2.51 (m, 1H), 2.40-2.26 (m,
1H), 1.71-1.68 (d, J ) 6.3 Hz, 3H). 13C NMR (50.3 MHz): δ
168.2 (Cquat, CO), 155.9 (Cquat), 139.5 (Cquat), 138.2 (Cquat), 133.7
(CH), 130.7 (CH), 129.0 (CH), 128.9 (CH), 128.7 (Cquat), 128.1
(CH), 128.0 (Cquat), 127.1 (CH), 124.3 (CH), 57.9 (CH), 27.8
(CH2), 20.4 (CH2), 17.9 (CH3). IR (CH2Cl2): ν˜ 1718 cm-1. MS
(FD): m/z (%) 342.0 (0.9), 341.0 (6.2), 340.0 (20.0), 339.0 (M+,
100), 337.0 (3.0); C19H17NO3S (339.0). HR-MS (EI): m/z found
339.0916, calcd 339.0929.
2.28-2.13 (m, 6H), 1.73-1.67 (m, 1H), 1.48-1.38 (m, 1H). 13
C
NMR (50.3 MHz): δ 216.4, 215.4, 145.4, 142.0, 140.1, 134.7,
132.3, 128.8, 126.9, 117.8, 85.5, 57.4, 51.6, 39.9, 31.8, 24.4. IR
(CH2Cl2): ν˜ 2010, 1953, 1536 cm-1. Anal. Calcd for C22H23
-
FeNO4S (452.85): C, 58.30; H, 5.08; N, 3.09; Found: C, 58.30;
H, 5.42; N, 2.91.
{(1-3-η3)-[2,3:3′,4′]-([3:3′]-o-H yd r oxyp h en yl)-5′-(p r op -
2′′-en -1′′yl)(1′-p h en ylsu lfon yl)-1′,5′-d ih yd r o-2′H-p yr r ol-2′-
on e}-ca r b on ylcyclop en t a d ien ylir on (8a ). According to
method B treatment of the imine 4e (540 mg, 1.137 mmol)
with 1.6 equiv of (allyl)MgCl gave 494 mg (84%) of 8a as an
orange-red solid. Recrystallization of 8a in CH2Cl2/petroleum
ether gave deep red crystals. After addition of the Grignard
reagent to the reaction mixture at room temperature an
immediate change in color and a temperature increase was
1-Met h yl-1,2,3,4,5-p en t a h yd r ob en zo[e]isoin d ol-3-on e
(6f). Rf ) 0.05. 1H NMR (400 MHz): δ 7.27-7.21 (m, 3H), 7.14-
7.12 (m, 1H), 7.09 (br s, 1H), 4.57 (m, 1H), 2.94-2.86 (m, 2H),
2.69-2.63 (m, 1H), 2.45-2.35 (m, 1H), 1.46-1.44 (d, J ) 6.2
Hz, 3H). 13C NMR (100.6 MHz): δ 173.1 (Cquat, CdO), 154.1
(Cquat), 137.7 (Cquat), 131.0 (Cquat), 129.4 (CH), 129.1 (Cquat),
128.6 (CH), 126.7 (CH), 123.6 (CH), 52.2 (CH), 28.2 (CH2), 19.8
(CH2), 18.2 (CH3). IR (CH2Cl2): ν˜ 1691 cm-1. MS (FD): m/z

3534 Organometallics, Vol. 19, No. 18, 2000
Amrhein et al.
observed. The reaction mixture was stirred for another 60 min
at room temperature before it was added to brine (100 mL).
Mp: 160 °C dec. Rf ) 0.71. 1H NMR (400 MHz): δ 9.04 (s, 1H),
8.18-8.14 (dd, J ) 8.3 Hz, J ) 1.5 Hz, 2H), 7.67-7.49 (m,
3H), 7.01-6.93 (dt, J ) 6.8 Hz, J ) 1.0 Hz, 1H), 6.88-6.84
(dd, J ) 6.8 Hz, J ) 1.0 Hz, 1H), 6.45-6.37 (dt, J ) 6.8 Hz, J
) 1.0 Hz, 1H), 6.04-6.00 (d, J ) 7.8 Hz, 1H), 5.69-5.52 (m, J
) 14.1 Hz, J ) 9.3 Hz, J ) 7.3 Hz, 1H, CHdCH2), 5.09 (br s,
1H), 5.03-5.01 (d, J ) 3.9 Hz, 1H), 4.83-4.79 (dd, J ) 6.3
Hz, J ) 3.4 Hz, 1H), 4.67 (s, 5H), 3.78-3.76 (d, J ) 3.4 Hz,
1H), 2.99-2.96 (ddd, J ) 14.1 Hz, J ) 7.3 Hz, J ) 3.4 Hz,
1H), 2.90-2.79 (m, 1H), 2.19-2.17 (d, J ) 3.4 Hz, 1H). 13C
NMR (50.3 MHz): δ 216.0 (Cquat, CO), 179.6 (Cquat, CO), 155.2
(Cquat), 138.9 (Cquat), 134.2 (CH), 130.7 (CH), 129.1 (CH), 128.6
(CH), 128.3 (CH), 125.9 (Cquat), 122.7 (CH), 120.6 (CH2), 119.8
(CH), 119.1 (CH), 98.2 (Cquat), 81.5 (CH), 68.0 (CH), 58.9 (Cquat),
42.0 (CH2), 34.7 (CH2). IR (CH2Cl2): ν˜ 1979, 1669 cm-1. IR
(KBr): ν˜ 3430, 3108, 3084, 3016, 2928, 1957, 1914, 1669, 1493,
1485, 1449, 1362, 1348, 1318, 1170, 1153, 1138, 1084, 1058,
993 cm-1. MS (FD): m/z (%) 517.4 (M+, 100%). Anal. Calcd
for C26H23FeNO5S (517.4): C, 60.36; H, 4.45; N, 2.71; Found:
C, 60.05; H, 4.42; N, 2.66.
Anal. Calcd for C26H25FeNO5 (518.85): C, 60.13; H, 4.82; N,
2.70. Found: C, 60.19; H, 4.79; N, 2.69.
{(1-3-η3)-[2,3:3′,4′]-([3:3′]-o-H yd r oxyp h en yl)-5′-(p r op -
2′′-en -1′′yl)(1′-(o-ben zoic a cid (-)-m en th yl ester )su lfon -
yl)-1′,5′-dihydro-2′H-pyrrol-2′-one}carbonylcyclopentadien-
ylir on (8c). According to method B treatment of the imine 4f
(230 mg, 0.35 mmol) with (allyl)MgCl gave 137 mg (56% as a
mixture of diastereomers; by 1H and 13C NMR spectroscopy
four isomers were detectable; ratio 3:3:1:1) of 8c as a red
amorphous solid. The Grignard reagent was added at -80 °C,
and stirring was continued for 15 min at that temperature
and 6 h 45 min at room temperature. The reaction mixture
was added to brine (90 mL) with stirring and was worked up
20
by following the general procedure. Rf ) 0.69. RD ) +72.2°
1
(c ) 0.2; CH2Cl2). H NMR (400 MHz, major:minor 55:45, the
asterisk denotes minor): δ 9.08, 9.07* (s, 1H), 8.54-8.52 (m,
1H), 7.67-7.63 (m, 2H), 7.42-7.40 (m, 1H), 7.16-7.14 (m, 1H),
7.01-6.97 (t, J ) 7.3 Hz, 1H), 6.89-6.87 (m, 1H), 6.47-6.43
(dt, J ) 7.3 Hz, J ) 1.2 Hz, 1H), 6.10-6.08 (d, J ) 7.6 Hz,
1H), 5.92-5.81, 5.80-5.66* (m, J ) 14.1 Hz, J ) 10.0 Hz, J )
7.3 Hz, 1H, CHdCH2), 5.21-5.10 (m, 2H), 4.95-4.92 (m, 1H),
4.49, 4.47* (s, 5H), 3.74-3.73 (d, J ) 1.8 Hz, 1H), 3.11-3.04,
2.85-2.72* (m, 2H), 2.17-2.16 (d, J ) 1.8 Hz, 1H), 2.08-2.04
(m, 1H), 1.75-1.70 (m, 2H), 1.55-1.42 (m, 1H), 1.20-1.09 (m,
2H), 0.99-0.82 (m, 12H). 13C NMR (50.3 MHz, the asterisk
denotes minor): δ 216.0, 180.5, 167.4, 155.2, 136.6, 133.9,
133.6, 131.1*, 131.0, 130.8*, 130.6, 129.1*, 128.5, 128.3, 128.1*,
126.1, 125.3, 122.6, 120.8, 120.6, 119.8, 119.0, 98.9, 80.9, 76.8,
68.3, 47.1, 46.9*, 43.0*, 42.8, 40.5, 40.1*, 34.2, 34.0, 33.9*, 31.6,
26.2*, 25.9, 23.3*, 23.2, 22.1, 20.9, 16.1*, 16.0. IR (CH2Cl2): ν˜
1989, 1696, 1669 cm-1. MS (FD): m/z (%) 701.4 (17.5), 700.3
(40.2), 699.4 (M+, 100), 671.3 (M+ - CO, 14.8); C37H41FeNO7S
(699).
{(1-3-η3)-[2,3:3′,4′]([3:3′]-o-Hyd r oxyp h en yl)-5′-n -p r op yl-
(1′-p h e n y lsu lfo n yl)-1′,5′-d ih y d r o -2′H -p y r r o l-2′-on e }-
ca r bon ylcyclop en ta d ien ylir on (8b). According to method
B treatment of the imine 4e (301 mg, 0.63 mmol) with
nPrMgCl in 1,2-dichloroethane (10 mL) gave 80 mg (24%) of
8b as an orange oil. After addition of nPrMgCl to the reaction
mixture an immediate change in color and a temperature
increase was observed. After it was stirred for 72 h at room
temperature, the reaction mixture was added to brine (80 mL)
with stirring and worked up by following the general proce-
dure. Rf ) 0.67. 1H NMR (400 MHz): δ 9.15 (s, 1H), 8.15-8.12
(dd, J ) 7.9 Hz, J ) 1.5 Hz, 2H), 7.64-7.60 (dt, J ) 7.3 Hz, J
) 2.0 Hz, 1H), 7.55-7.51 (t, J ) 7.3 Hz, 2H), 6.99-6.95 (dt, J
) 7.3 Hz, J ) 1.5 Hz, 1H), 6.88-6.86 (dd, J ) 7.0 Hz, J ) 1.2
Hz, 1H), 6.45-6.41 (dt, J ) 7.3 Hz, J ) 1.2 Hz, 1H), 6.01-
5.99 (dd, J ) 7.8 Hz, J ) 1.2 Hz, 1H), 4.78-4.75 (dd, J ) 6.7
Hz, J ) 2.9 Hz, 1H), 4.67 (s, 5H), 3.80-3.79 (d, J ) 3.3 Hz,
1H), 2.21-2.17 (d, J ) 3.2 Hz, 1H), 2.22-2.14 (m, 1H), 2.07-
1.98 (m, 1H), 1.51-1.44 (m, 1H), 1.17-1.12 (m, 1H), 0.88-
0.85 (t, J ) 7.3 Hz, 3H). 13C NMR (100.6 MHz): δ 214.9, 178.6,
154.2, 138.0, 132.9, 127.9, 127.5, 127.1, 124.9, 121.2, 118.7,
118.1, 97.7, 80.5, 67.4, 38.5, 33.2, 15.6, 12.6. IR (CH2Cl2): ν˜
1978, 1674 cm-1. IR (KBr): ν˜ 3436, 2966, 2932, 2874, 1970,
1729, 1663, 1449, 1364, 1339, 1186, 1174, 1152, 1089, 1062,
732, 592 cm-1. MS (FD): m/z (%) 519.3 (M+, 100), 369.1 (79.3).
Ack n ow led gm en t. We thank Dr. D. Schollmeyer for
the X-ray structure analysis. Financial support from the
Kalkhof-Rose-Stiftung, the Deutsche Forschungsge-
meinschaft, and the Fonds der Chemischen Industrie
is gratefully acknowledged.
Su ppor tin g In for m ation Available: Tables giving atomic
coordinates, bond lengths and angles, anisotropic thermal
parameters, and experimental details of X-ray study for 8a .
This material is available free of charge via the Internet at
http://pubs.acs.org.
OM000235J