Highly stereoselective synthesis of N-substituted π-conjugated phthalimides

Article abstract of DOI:10.1016/j.tet.2012.03.012

A new regio- and stereoselective synthesis of (E)-N-(2-arylvinyl) phthalimides as well as phthalimide-containing (E,E)-buta-1,3-dienes and (E)-but-1-en-3-ynes has been developed. The one-pot ruthenium-catalyzed silylative coupling/iododesilylation sequenc

Full text of DOI:10.1016/j.tet.2012.03.012

Tetrahedron 68 (2012) 3545e3551
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Highly stereoselective synthesis of N-substituted
p-conjugated phthalimides
*
ꢀ
Piotr Pawluc , Adrian Franczyk, Je˛drzej Walkowiak, Grzegorz Hreczycho, Maciej Kubicki,
Bogdan Marciniec
Department of Organometallic Chemistry, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznan, Poland
a r t i c l e i n f o
a b s t r a c t
Article history:
A new regio- and stereoselective synthesis of (E)-N-(2-arylvinyl)phthalimides as well as phthalimide-
containing (E,E)-buta-1,3-dienes and (E)-but-1-en-3-ynes has been developed. The one-pot ruthenium-
catalyzed silylative coupling/iododesilylation sequence provides (E)-N-(2-iodovinyl)phthalimide 1, which
undergoes palladium-catalyzed SuzukieMiyaura or Sonogashira cross-coupling to afford stereodefined
Received 5 December 2011
Received in revised form 15 February 2012
Accepted 5 March 2012
Available online 12 March 2012
highly
p-conjugated phthalimides and functionalized dienimides containing phthalimide groups.
Ó 2012 Elsevier Ltd. All rights reserved.
Keywords:
Phthalimides
Silylative coupling
Iododesilylation
SuzukieMiyaura coupling
Sonogashira coupling
1. Introduction
systems, including natural products.11 Despite their synthetic util-
ity and biological potential, the synthetic routes available for the
Enamides and their derivatives are versatile building blocks in
organic synthesis, especially for enantioselective hydrogenation
and for stereoselective CeC and CeN bond formation reactions.1
Isoindole-1,3-diones, commonly known as phthalimides, are key
structural units in a variety of biologically important compounds.
Several fungicides,2 metabolic drugs,3 and functional materials4
contain alkenyl-substituted phthalimides as key structural ele-
ments. A number of transition metal-catalyzed approaches for the
selective synthesis of N-alkenyl-substituted phthalimides have re-
cently emerged. Among them, protocols based on the ruthenium-
catalyzed addition of phthalimide to terminal alkynes,5 copper-
catalyzed N-vinylation of phthalimide by alkenyl halides,6 alkenyl
boronic acids7 or potassium alkenyltrifluoroborate,8 and palladium-
catalyzed oxidative amination of alkenes9 stand out for their syn-
thetic versatility and efficiency. N-Styrylphthalimides have also
been obtained via palladium-catalyzed Heck arylation of N-vinyl-
phthalimide with aryl halides, however, the main drawback found
stereoselective preparation of dienamides are limited.12 Thus,
acyclic N-(1,3-butadienyl)amides have been made by olefination of
N-formyl imides,13 ruthenium-catalyzed co-oligomerization of N-
vinylamides with alkynes,14 titanium-mediated coupling of yna-
mides with alkynes15 or cobalt-mediated hydroaminative coupling
of diynes with amides.16
a,
g-Dienamide esters have also been
obtained by stereospecific palladium-catalyzed SuzukieMiyaura
cross-coupling of
b-bromoenamide esters with vinyl boronic
acids.17 Nevertheless, to the best of our knowledge, no examples
of a general method for the synthesis of stereodefined (E,E)-1,3-
dienes containing N-substituted phthalimide groups have been
given so far.18
b-Iodoenamides are synthetically versatile variants of enamides,
which offer rapid access to -metalated enamides that can serve as
b
acyl anion equivalents or can be involved in transition metal-
catalyzed reactions. In addition, stereodefined iodoenamides are
excellent candidates for use as coupling partners in palladium-
catalyzed cross-coupling reactions allowing regio- and stereo-
selective construction of complex enamide and dienamide de-
rivatives. Despite this versatility, there are only a few examples of
synthetic application of iodoenamides, presumably because of
for this reaction is the control of a- and b
-regioselectivity.10 Re-
cently, a regioselective protocol for the synthesis of (E)-N-styr-
ylphthalimides based on Heck arylation of N-vinylphthalimide in
the presence of oxime-derived palladacycles has been developed.10e
Dienamides and related compounds are important DielseAlder
partners that have been used for the preparation of polycyclic
difficulties in their synthesis.19 Smith and co-workers applied (Z)-
b-
iodovinyl butyramide as a Stille coupling partner in the synthesis of
the (Z,E)-dienamide unit of the marine natural product Lituarine
C.20 Isomeric iodoenamides have been shown to be versatile
reagents in Sonogashira couplings to yield enynamides.19b,21
* Corresponding author. Fax: þ48 618291508; e-mail address: piotrpaw@
ꢀ
amu.edu.pl (P. Pawluc).
0040-4020/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2012.03.012

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P. Pawluc et al. / Tetrahedron 68 (2012) 3545e3551
3546
Heterocyclic iodoenamides have also been applied in palladium-
catalyzed SuzukieMiyaura22 and Sonogashira23 couplings.
A flexible, one-pot, and stereoselective procedure for the syn-
thesis of iodoenamide building blocks would greatly improve cur-
rent approaches to the synthesis of enamide-containing natural
products and pharmaceutically relevant heterocyclic systems.
iododesilylation process disclosed for b
-silylenimides.28 Thus, by
sequencing the highly E-selective silylative coupling of N-vinyl-
phthalimide with a stereospecific iododesilylation, the stereo-
chemical fidelity of the product is preserved. During the course of
our experiments, we have found that molecular iodine (1.2 equiv)
in CH2Cl2 could also be employed for the iododesilylation of (E)-N-
(2-trimethylsilylvinyl)phthalimide at room temperature. However,
it seemed to be less effective than NIS and gave the product with
moderate yield and selectivity (GC yield 68%, E/Z¼7/3). In contrast,
when iodine monochloride ICl (1 equiv) in CH2Cl2 was applied, no
iododesilylation product was detected and decomposition of (E)-N-
(2-trimethylsilylvinyl)phthalimide was observed.
(E)-N-(2-Iodovinyl)phthalimide would offer
a synthetically
versatile variant of N-vinylphthalimide, which could be used as
a coupling partner in palladium-catalyzed cross-coupling reactions
allowing regio- and stereoselective construction of complex (E)-N-
(2-arylvinyl)phthalimides as well as (E,E)-N-(buta-1,3-dien-1-yl)
phthalimides and (E)-N-(but-1-en-3-yl)phthalimides.
In this paper we report the one-pot synthesis of a new building
blockd(E)-N-(2-iodovinyl)phthalimide 1 ((E)-2-(2-iodovinyl)-iso-
indoline-1,3-dione) from N-vinylphthalimide by a silylative cou-
plingeiododesilylation sequence and its application in the
palladium-catalyzed SuzukieMiyaura and Sonogashira cross-
After several attempts we have found that iododesilylation of
(E)-N-(2-trimethylsilylvinyl)phthalimide occurs efficiently also
when a 4/1 mixture of acetonitrile and toluene is employed as the
solvent without affecting either the reaction yield or stereo-
selectivity. This result prompted us to attempt the iododesilylation
step in one pot with silylative coupling without further purification
of the (E)-N-(2-trimethylsilylvinyl)-phthalimide intermediate
(Scheme 2).
coupling reactions to yield N-substituted highly
p-conjugated
phthalimide derivatives (Scheme 1).
Scheme 2. One-pot synthesis of key precursord(E)-N-(2-iodovinyl)-phthalimide 1.
In a typical procedure, N-vinylphthalimide, trimethylvinylsilane
(1/1.2 molar ratio) and RuHCl(CO)(PCy3)2 catalyst (2 mol %) were
dissolved in dry toluene (0.5 M concentration) and heated under an
Ar atmosphere in a Schlenk bomb flask fitted with a plug valve at
100 ꢀC for 24 h. Next, after cooling the reaction mixture to room
temperature, a 4-fold volume excess of acetonitrile and 2 equiv of
solid N-iodosuccinimide were added. Treatment of the silylative
coupling product with NIS caused iododesilylation in a stereospe-
cific manner, giving (E)-N-(2-iodovinyl)phthalimide 1 in high geo-
metrical purity (E/Z¼98/2) within 24 h. The reaction was quenched
with aqueous Na2S2O3, extracted with hexane, and concentrated to
dryness. Column chromatography of the resulting product (silica
gel, eluent: hexane/ethyl acetate 50/2) afforded pure compound 1
in 85% overall yield. The E-configuration of carbonecarbon double
bond in 1 was determined on the basis of the 1H and 13C NMR
spectra. Moreover, compound 1 proved to be a solid and yielded
a crystal amenable to X-ray structure determination (Fig. 1).29
Scheme 1. New synthetic strategy to highly p-conjugated N-substituted phthalimides.
In the past two decades, we have developed the silylative cou-
pling of olefins with vinyl-substituted organosilicon compounds
occurring in the presence of complexes containing initially or
generating in situ MeH and MeSi bonds.24 The silylative coupling,
in combination with subsequent desilylation reactions, such as
Hiyama cross-coupling and halodesilylation, appears to be a valu-
able step to provide highly conjugated p-electron compounds, such
as stilbenes, aryl-substituted polyenes, or styryl halides.24b
As we have previously reported, the silylative coupling of N-
vinylamides with vinylsilanes catalyzed by a rutheniumehydride
complex occurred stereoselectively to give (E)-N-(2-silylvinyl)am-
ides in good yields.25 On the basis of our recent results on the highly
stereoselective one-pot synthesis of (E)-b-arylvinyl halides from
functionalizedterminalalkenes,26 we envisaged that theruthenium-
catalyzed E-selective silylative coupling25 of commercially available
and inexpensive N-vinylphthalimide with trimethylvinylsilane fol-
lowed by N-iodosuccinimide-mediated iododesilylation27 could be
a valuable synthetic method for the one-pot conversion of N-vinyl-
phthalimide into (E)-N-(2-iodovinyl)phthalimide 1. The resulting
iodide could be used as a coupling partner for the stereoselective
synthesis of imide-functionalized alkenes, dienes, and enynes.
2. Results and discussion
Fig. 1. Perspective view of the molecule 1 (CCDC-707362). Ellipsoids are drawn at 50%
probability level, hydrogen atoms are shown as spheres of arbitrary radii.
The silylative coupling reaction of N-vinylphthalimide and tri-
methylvinylsilane (1.2 equiv) was conducted following the original
procedure (RuHCl(CO)(PCy3)2 catalyst (2 mol %), toluene, 24 h,
100 ꢀC, sealed ampoule under Ar atmosphere)25 to give exclusively
(E)-N-(2-trimethylsilylvinyl)phthalimide (GC yield 97%). Treatment
of (E)-N-(2-trimethylsilylvinyl)-phthalimide with 2 equiv of N-
iodosuccinimide (NIS) in acetonitrile at room temperature allowed
isolation of stereochemically pure (E)-N-(2-iodovinyl)phthalimide
1 in 89% yield. To the best of our knowledge, this is the first
This approach to (E)-N-(2-iodovinyl)phthalimide 1 provides
a very useful synthesis of various b-substituted vinylphthalimides
via elaboration of the resulting iodide functionality into other
substituents by using palladium-catalyzed cross-coupling pro-
cesses. Thus, to demonstrate the synthetic usefulness of 1, we in-
vestigated palladium-catalyzed SuzukieMiyaura and Sonogashira
coupling reactions.

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P. Pawluc et al. / Tetrahedron 68 (2012) 3545e3551
3547
The cross-coupling reactions of 1 with aryl boronic acids were
carried out under standard biphasic reaction conditions30 (toluene
(0.1 M), aqueous K2CO3 (3 equiv, 2 M), and ethanol (15 equiv)).
SuzukieMiyaura coupling of 1 with selected aryl boronic acids
(Table 1, entries 1e5) and heteroaryl boronic acid pinacol esters
(Table 1, entries 6e7) proceeded smoothly at 50 ꢀC in the presence
of Pd(PPh3)4 catalyst (5 mol %) to give the corresponding (E)-N-(2-
arylvinyl)phthalimides 2aeg within 24 h in good yields (61e90%).
As the boronic acids were used in slight excess (1.1 equiv), the
formation of by-productsdsymmetrical biphenyl derivatives was
observed (5e10%) in the reaction mixture, however, they could be
separated by column chromatography. In an effort to explore the
scope of the method, we have screened the coupling of 1 with para-
substituted aryl boronic acids as well as heteroaryl boronic acid
esters containing thienyl- and furyl-groups. Under these condi-
tions, boronic acid coupling partners bearing functional groups,
such as eMe, eBr, and eCH]CH2, reacted successfully to give the
corresponding (E)-N-(2-arylvinyl)phthalimides in high yields
(Table 1), irrespective of the substituent electronic character. In
most cases, the E-double bond geometry was strongly favored, with
approximately 95/5 to 99/1 E/Z ratio (for arylvinyl derivatives) and
92/8 to 94/6 ratio (for heteroaryl derivatives) as measured by 1H
NMR spectroscopy. The optimal conditions established for the re-
action of compound 1 with aryl boronic acids were also applied to
(E)-arylvinyl boronic acids, providing good yields (72e90%) of the
desired (E,E)-buta-1,3-dienylphthalimide derivatives (2hej). Thus,
the coupling reactions were performed in a toluene/ethanol mix-
ture using Pd(PPh3)4 (5 mol %) as catalyst, in the presence of a 2 M
aqueous solution of K2CO3 (3 equiv) at 50 ꢀC (Scheme 3).
It is worth noting that the SuzukieMiyaura coupling processes
proceeded in a highly stereoselective manner to yield products
containing (E,E)-dienes as predominant products (isomeric purity
over 90%), however, partial isomerization leading to small amounts
of the respective (E,Z)-isomers was also detected using the GCeMS
method (Table 1). In all cases, trace amounts of by-productsd(E,E)-
1,4-diarylbuta-1,3-dienes formed by competitive homo-coupling of
Table 1
Synthesis of (E)-N-(2-arylvinyl)phthalimides and (E,E)-N-(buta-1,3-dien-1-yl)phthalimides
Entry
1
Compound
R
Product structure
Isomeric puritya
Yieldb (%)
90
2a
Ph
95/5 (E/Z)
2
3
4
5
2b
2c
2d
2e
4-MeC6H4
96/4 (E/Z)
95/5 (E/Z)
99/1 (E/Z)
99/1 (E/Z)
85
76
79
75
4-BrC6H4
4-CH2]CHC6H4
1-Naphthyl
6
2f
5-Methylthienyl
92/8 (E/Z)
82
7
8
2g
2h
5-Methylfuryl
94/6 (E/Z)
61
90
(E)-PhCH]CH
93/7 (E,E)/(E/Z)
9
2i
2j
(E)-4-MeC6H4CH]CH
(E)-3-FC6H4CH]CH
90/10 (E,E)/(E,Z)
92/8 (E,E)/(E,Z)
85
72
10
a
Determined by GCeMS.
Isolated yields.
b

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P. Pawluc et al. / Tetrahedron 68 (2012) 3545e3551
3548
given conditions. Stereodefined products 3aec can be used as
a lynchpin reagents for further catalytic transformations.
Scheme 3. SuzukieMiyaura coupling of (E)-N-(2-iodovinyl)phthalimide 1 with aryl
boronic acids and (E)-arylvinyl boronic acids.
the arylvinyl boronic acids (used in slight excess) were observed,
however, they can be separated by column chromatography.
Compounds 2aej were isolated and spectroscopically charac-
terized.29 The E-configuration of the double bonds of (E)-2-(4-meth
ylstyryl)isoindoline-1,3-dione 2b (Fig. 2), 2-((E,E)-4-phenylbuta-
1,3-dien-1-yl)isoindoline-1,3-dione 2h (Fig. 3), and 2-((E,E)-4-(3-
fluorophenyl)buta-1,3-dien-1-yl)isoindoline-1,3-dione 2j (Fig. 4)
was further confirmed by single-crystal X-ray diffraction analysis.29
Scheme 4. SuzukieMiyaura coupling of 1 with ethylenediboronic acid bis(pinacol)
esters.
Table 2
Synthesis of tetrasubstituted buta-1,3-dienes
Compound
R1
R2
E/Za
Yield (%)b
3a
3b
3c
Ph
H
COOMe
Ph
n-Bu
n-Bu
99/1
99/1
99/1
85
69
81
a
Configuration of PhthNCH]CHe double bond determined by 1H NMR
spectroscopy.
b
Isolated yield.
Finally, we decided to evaluate the utility of b-iodoenimide 1 in
palladium-catalyzed Sonogashira coupling31 with the aim of
obtaining new enyne building blocks containing phthalimide units.
Sonogashira coupling of 1 with selected alkynes (Table 3) pro-
ceeded smoothly at room temperature in the presence of
a PdCl2(PPh3)2/CuI catalytic system to give the corresponding (E)-
N-(but-1-en-3-yn-1-yl)phthalimides 4aef in good yields (60e84%).
As the terminal alkynes were used in excess, formation of by-pro-
ductsdsymmetrical 1,3-diynes were observed (5e10%) in the re-
action mixture, however, they can be separated by column
Fig. 2. Perspective view of the molecule 2b (CCDC-832076). Ellipsoids are drawn at
50% probability level, hydrogen atoms are shown as spheres of arbitrary radii.
Table 3
Synthesis of (E)-N-(but-1-en-3-yn-1-yl)phthalimides
Entry
1
R
Product structure
E/Za
Yieldb (%)
Fig. 3. Perspective view of the molecule 2h (CCDC-832079). Ellipsoids are drawn at
50% probability level, hydrogen atoms are shown as spheres of arbitrary radii.
Ph
94/6 83
99/1 84
4a
2
1-Naphthyl
4b
4c
4d
3
4
SiMe3
98/2 70
94/6 82
Fig. 4. Perspective view of the molecule 2j (CCDC-742617). Ellipsoids are drawn at 50%
probability level, hydrogen atoms are shown as spheres of arbitrary radii.
C6H10(OSiMe3)
As an extension to the present study we have found that com-
pound 1 can be also used in the synthesis of functionalized tetra-
substituted buta-1,3-dienes containing
a phthalimide group
(Scheme 4). SuzukieMiyaura cross-coupling of 1 with 2 equiv
of ethylenediboronic acid bis(pinacol) esters (substituted (Z)-
1,2-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)ethenes) per-
formed under optimal conditions established for the reaction of 1
with aryl boronic acid pinacol esters (Pd(PPh3)4 catalyst (5 mol %),
toluene (0.05 M), aqueous K2CO3 (3 equiv, 2 M), and ethanol
(15 equiv)) provides monophthalimido-substituted buta-1,3-dienes
containing boryl groups (Table 2) in good yield (69e85%). Only
trace amounts of bis(phthalimido)-substituted products (trienes
containing two phthalimide units) have been observed under the
5
6
n-C6H13
97/3 75
99/1 60
4e
4f
4-C6H4(BO2C6H12
)
a
Determined by GCeMS.
Isolated yields.
b

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P. Pawluc et al. / Tetrahedron 68 (2012) 3545e3551
3549
chromatography. In an effort to explore the scope of the method,
we have screened the coupling of 1 with alkyl-, aryl-, and
trimethylsilyl-substituted acetylenes (Table 3). All the reactions
were stereospecific and in most cases, the (E)-double bond geom-
etry was strongly favored, with approximately 94/6e99/1 E/Z ratio
as measured by 1H NMR spectroscopy (Scheme 5).
(dd, 1H, J¼15.0, 0.5 Hz); 13C NMR (CDCl3, 75 MHz)
d
¼164.2, 160.9,
143.6, 133.9, 133.8, 127.6, 127.5, 115.8, 115.5. 76.1; MS (EI) m/z¼299
(Mþ, 25%),172 (100),144 (10),127 (12),116 (22),104 (25), 89 (20), 76
(24). HRMS (m/z)¼298.9455, calcd for C10H6INO2: 298.9443.
4.2. Representative procedure for the SuzukieMiyaura cross-
coupling of 1 with boronic acids or boronic acid pinacol esters
To a solution of Pd(PPh3)4 (0.017 mmol, 19.3 mg), (E)-N-(2-
iodovinyl)phthalimide (0.334 mmol, 100 mg), and 0.337 mmol of
boronic acid (for the synthesis of compounds 2aee and 2hej) or
boronic acid pinacol ester (for compounds 2f,g) in toluene (3.3 mL,
0.1 M) an aqueous K2CO3 (1 mmol, 0.5 mL, 2 M) and ethanol
(5 mmol, 230 mg, 0.29 mL) were added. The reaction mixture was
stirred at 50 ꢀC under an argon atmosphere for 24 h. The organic
layer was concentrated and the crude product was preloaded onto
silica. Products were purified by silica gel chromatography, eluting
with EtOAc in n-hexaned0e50%.
Scheme 5. Sonogashira coupling of 1 with terminal alkynes.
The structural assignment of the enyne 4ad(E)-2-(4-phenylbut-
1-en-3-yn-1-yl)isoindoline-1,3-dione was confirmed by X-ray
crystallography.29 The configuration around the double bond in 4a
is (E)-, as is evident from the value of the NeC]CeC torsion angles:
179.93(13)ꢀ (Fig. 5).
4.2.1. (E)-2-Styrylisoindoline-1,3-dione (2a).10e Pale yellow solid,
mp 188e189 ꢀC; Rf (50% EtOAc/hexane)¼0.42; IR, nmax (KBr)¼3025,
2952, 1714, 1639, 1466, 1581, 1382, 1108 cmꢁ1 1H NMR (CDCl3,
;
300 MHz)
d
¼7.92e7.88 (m, 2H), 7.80e7.74 (m, 2H), 7.65 (d, 1H,
J¼15.6 Hz), 7.50e7.46 (m, 2H), 7.39e7.33 (m, 3H); 7.29e7.23 (m,
1H); 13C NMR (CDCl3, 75 MHz)
d¼166.5, 135.9, 134.6, 131.7, 128.7,
127.6, 126.2, 123.7, 120.2, 117.6. MS (EI) m/z¼249 (Mþ, 100%), 232
(22), 220 (25), 204 (40),165 (15),128 (24),102 (38),104 (34), 76 (57),
50 (53); HRMS (m/z)¼249.0793, calcd for C16H11NO2: 249.0790.
4.2.2. (E)-2-(4-Methylstyryl)isoindoline-1,3-dione
(2b).10e Yellow
Fig. 5. Perspective view of the molecule 4a (CCDC-790990). Ellipsoids are drawn at
50% probability level, hydrogen atoms are shown as spheres of arbitrary radii.
solid, mp 174 ꢀC; Rf (50% EtOAc/hexane)¼0.46; IR, nmax (KBr)¼3070,
3012, 2850, 1716, 1649, 1465, 1382, 1082 cmꢁ1 1H NMR (CDCl3,
;
300 MHz)
d
¼7.91e7.87 (m, 2H), 7.77e7.74 (m, 2H), 7.62 (d, 1H,
3. Conclusions
J¼15.1 Hz), 7.37 (d, 2H, J¼8.1 Hz), 7.32 (d, 1H, J¼15.1 Hz), 7.16 (d, 2H,
J¼8.1 Hz), 2.36 (s, 3H); 13C NMR (CDCl3, 75 MHz)
¼166.5, 137.6,
d
In conclusion, the one-pot ruthenium-catalyzed silylative cou-
pling of N-vinylphthalimide with trimethylvinylsilane followed by
NIS-mediated iododesilylation provides facile entry to (E)-N-(2-
iodovinyl)phthalimide, which is a versatile building block shown
to undergo subsequent palladium-catalyzed SuzukieMiyaura and
Sonogashira coupling reactions en route to
vinylphthalimides and new stereodefined phthalimide-containing
di- and tetrasubstituted buta-1,3-dienes. Further results on the
application of this strategy to the synthesis of highly
triene systems will be reported in due course.
134.5, 133.1, 131.7, 129.4, 126.1, 123.6, 120.3, 116.8, 21.2; MS (EI) m/
z¼263 (Mþ, 15%), 183 (10), 167 (12), 149 (20), 128 (22), 99 (35), 83
(38), 57 (40). HRMS (m/z)¼263.0941, calcd for C17H13NO2: 263.0946.
4.2.3. (E)-2-(4-Bromostyryl)isoindoline-1,3-dione (2c). Yellow solid,
mp 173e174 ꢀC; Rf (50% EtOAc/hexane)¼0.48; IR, nmax (KBr)¼3069,
b-functionalized N-
1713, 1636, 1465, 1383, 1083 cmꢁ1 1H NMR (CDCl3, 300 MHz)
;
d
¼7.92e7.87 (m, 2H), 7.80e7.74 (m, 2H), 7.60 (d, 1H, J¼15.1 Hz),
7.49e7.43 (m, 2H), 7.38e7.29 (m, 3H); 13C NMR (CDCl3, 75 MHz)
p-conjugated
d
¼166.3, 135.2, 134.6, 131.8, 131.7, 131.6, 127.8, 127.7, 125.0, 123.7,
118.9, 118.1; MS (EI) m/z¼329 ([Mþ2]þ 100%), 327 (90), 282 (10),
4. Experimental section
248 (15), 204 (14),186 (65),104 (33), 76 (58), 50 (50), 28 (40); HRMS
79
(m/z)¼326.9903, calcd for C16
H BrNO2: 326.9895.
10
4.1. Synthesis of (E)-N-(2-iodovinyl)phthalimide (1)
4.2.4. (E)-2-(4-Vinylstyryl)isoindoline-1,3-dione (2d). White solid,
mp 180e181 ꢀC; Rf (50% EtOAc/hexane)¼0.50; IR, nmax (KBr)¼3077,
3043, 2985, 2922, 2851, 1912, 1720, 1646, 1509, 1465, 1381,
A mixture consisting of N-vinylphthalimide (2.0 g, 11.5 mmol),
vinyltrimethylsilane (2.03 mL, 13.8 mmol), RuHCl(CO)(PCy3)2
(0.167 g, 0.23 mmol), and 23 mL of dry toluene was placed under an
argon atmosphere in a 150 mL Schlenk bomb flask fitted with a plug
valve and heated at 100 ꢀC for 24 h to complete the reaction (GC
analysis). Next, after cooling the reaction mixture to room temper-
ature, 92 mL of acetonitrile and N-iodosuccinimide (5.18 g,
23.0 mmol) were added and the mixture was stirred for 24 h at room
temperature. After this time the solvents were evaporated and the
reaction mixture was quenched with aqueous Na2S2O3, extracted
with hexane, and concentrated to dryness. The final product was
purified by column chromatography on silica gel, eluting with n-
hexane/EtOAc (50/2). Rf (4% EtOAc/hexane)¼0.48; Yield: 85%. Pale
yellow crystals, mp 121e122 ꢀC; IR, nmax (KBr)¼3110, 2964, 1718,
1085 cmꢁ1
;
1H NMR (CDCl3, 300 MHz)
d
¼7.92e7.89 (m, 2H),
7.78e7.75 (m, 2H), 7.64 (d, 1H, J¼15.1 Hz), 7.46e7.34 (m, 5H), 6.72
(dd, 1H, J¼17.5, 10.9 Hz), 5.76 (dd, 1H, J¼17.5, 1.0 Hz), 5.25 (dd, 1H,
J¼10.9, 1.0 Hz); 13C NMR (CDCl3, 75 MHz)
¼166.9, 136.9, 136.4,
d
135.5, 134.5, 131.7, 126.6, 126.3, 123.7, 119.8, 117.5, 113.8; MS (EI) m/
z¼276 ([Mþ1]þ 25%), 275 (100), 128 (25), 76 (14), 50 (10); HRMS
(m/z)¼275.0938, calcd for C18H13NO2: 275.0946.
4.2.5. (E)-2-(2-(Naphthalen-1-yl)vinyl)isoindoline-1,3-dione
(2e). White solid, mp 148e149 ꢀC; Rf (50% EtOAc/hexane)¼0.52; 1H
NMR (CDCl3, 300 MHz)
d
¼8.42 (d, 1H, J¼14.9 Hz), 8.19 (d, 1H,
J¼7.9 Hz), 7.95e7.46 (m, 10H), 7.36 (d, 1H, J¼14.9 Hz); 13C NMR
1612, 1466, 1377, 1262, 1220 cmꢁ1
;
1H NMR (CDCl3, 300 MHz):
(CDCl3, 75 MHz)
d
¼166.5, 134.6, 133.7, 133.6, 131.7, 131.4, 128.5,
d¼7.40 (d,1H, J¼15.0 Hz), 7.30e7.24 (m, 2H), 7.07e6.99 (m, 2H), 6.76
128.1, 126.2, 125.9, 125.7, 124.0, 123.7, 123.2, 119.5, 117. 8; MS (EI) m/

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P. Pawluc et al. / Tetrahedron 68 (2012) 3545e3551
3550
z¼299 (Mþ, 50%), 152 (100), 104 (12), 76 (20), 50 (14); HRMS (m/z)¼
and ethanol (5 mmol, 230 mg, 0.29 mL). The reaction mixture was
stirred at 50 ꢀC under argon atmosphere for 24 h. The organic layer
was concentrated and the crude product was preloaded onto silica.
Products 3aec were purified by silica gel chromatography, eluting
with EtOAc in n-hexaned0e50%.
299.0924, calcd for C20H13NO2: 299.0946.
4.2.6. (E)-2-(2-(5-Methylthiophen-2-yl)vinyl)isoindoline-1,3-dione
(2f). White solid, mp 159e160 ꢀC; Rf (50% EtOAc/hexane)¼0.43; IR,
nmax (KBr)¼3093, 3045, 2955, 2925, 2854, 1718, 1609, 1466, 1381,
1225, 1099, 1086 cmꢁ1; 1H NMR (CDCl3, 300 MHz)
d
¼7.90e7.87 (m,
4.3.1. 2-((1E,3Z)-3,4-Diphenyl-4-(4,4,5,5-tetramethyl-1,3,2-
dioxaborolan-2-yl)buta-1,3-dien-1-yl)isoindoline-1,3-dione
(3a). Yellow solid, mp 172e173 ꢀC; Rf (50% EtOAc/hexane)¼0.58; IR,
nmax (KBr)¼3114, 3097, 3077, 2982, 2928, 2854, 1781, 1723, 1626,
2H), 7.76e7.67 (m, 3H), 7.12 (d,1H, J¼14.9 Hz), 6.86 (d,1H, J¼3.3 Hz),
6.65e6.63 (m, 1H), 2.48 (s, 3H); 13C NMR (CDCl3, 75 MHz)
d
¼166.3,
139.1, 138.1, 134.4, 131.7, 126.6, 125.7, 123.6, 115.8, 114.7, 15.6; MS (EI)
m/z¼270 ([Mþ1]þ 20%), 269 (100), 122 (30), 121 (18), 76 (13), 50
(20); HRMS (m/z)¼269.0494, calcd for C15H11NO2S: 269.0501.
1547, 1441, 1372, 1298, 1212, 1099, 1086 cmꢁ1 1H NMR (CDCl3,
;
300 MHz)
d
¼8.26 (d, 1H, J¼14.6 Hz), 7.87e7.84 (m, 2H), 7.73e7.71
(m, 2H), 7.19e7.15 (m, 2H), 7.06e6.98 (m, 2H), 6.92e6.89 (m, 6H),
6.58 (d, 1H, J¼14.6 Hz), 1.42 (s, 12H); 13C NMR (CDCl3, 75 MHz)
4.2.7. (E)-2-(2-(5-Methylfuran-2-yl)vinyl)isoindoline-1,3-dione
(2g). Pale yellow oil; Rf (50% EtOAc/hexane)¼0.44; IR, nmax (KBr)¼
3090, 3065, 2956, 2919, 2850, 1722, 1538, 1463, 1385, 1293, 1209,
d
¼166.0, 149.7, 141.2, 138.2, 134.4, 131.7, 130.4, 129.4, 127.9, 127.3,
126.9, 125.5, 123.6, 123.3, 122.6, 84.1, 24.8; MS (EI) m/z¼477 (Mþ,
2%), 366 (25), 365 (100), 104 (44), 76 (25); HRMS (m/z)¼477.2104,
calcd for C30H28BNO4: 477.2111.
1101, 1087 cmꢁ1; 1H NMR (CDCl3, 300 MHz):
d
¼7.89e7.86 (m, 2H),
7.76e7.72 (m, 2H), 7.40 (d, 1H, J¼14.7 Hz), 7.27 (d, 1H, J¼14.7 Hz),
6.21 (d, 1H, J¼3.2 Hz), 5.98 (dd, 1H, J¼3.2, 0.9 Hz), 2.33 (s, 3H); 13C
NMR (CDCl3, 75 MHz):
d
¼166.7, 152.2, 135.4, 134.4, 131.7, 123.6,
4.3.2. 2-((1E,3E)-4-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)
octa-1,3-dien-1-yl)isoindoline-1,3-dione (3b). Pale yellow solid, mp
192e193 ꢀC; Rf (50% EtOAc/hexane)¼0.56; IR, nmax (KBr)¼2994,
114.9, 110.3, 109.2, 107.6, 13.7; MS (EI) m/z¼254 ([Mþ1]þ 20%), 253
(100), 210 (16), 106 (20), 76 (10), 50 (20); HRMS (m/z)¼253.0732,
calcd for C15H11NO3: 253.0739.
2979, 2931, 2873,1721,1618,1468,1332,1273,1222,1142, 970 cmꢁ1
;
1H NMR (CDCl3, 300 MHz)
d
¼8.02 (dd,1H, J¼14.5,11.6 Hz), 7.88e7.85
4.2.8. 2-((1E,3E)-4-Phenylbuta-1,3-dien-1-yl)isoindoline-1,3-dione
(m, 2H), 7.74e7.70 (m, 2H), 6.85 (d, 1H, J¼14.5 Hz), 6.56 (d, 1H,
(2h). Pale yellow needles, mp 119e120 ꢀC; Rf (50% EtOAc/hexane)¼
J¼11.6 Hz), 2.22 (t, 2H, J¼6.9 Hz), 1.42e1.25 (m, 16H), 0.91e0.85 (t,
0.45; 1H NMR (300 MHz, CDCl3):
d
¼7.90e7.86 (m, 2H), 7.78e7.74
3H, J¼6.9 Hz); 13C NMR (CDCl3, 75 MHz)
¼166.2,141.5, 134.4, 131.8,
d
(m, 2H), 7.48e7.23 (m, 6H), 6.98 (d, 1H, J¼14.4 Hz), 6.86e6.78 (dd,
123.5, 120.9, 120.7, 83.9, 36.6, 32.3, 29.7, 24.8, 22.5, 14.1; MS (EI) m/
z¼381 (Mþ, 25%), 338 (32), 274 (50), 252 (15), 238 (100), 237 (36),
208 (31),192 (28),148 (20),130 (50), 83 (48), 76 (18), 54 (25); HRMS
(m/z)¼381.2132, calcd for C22H28NO4B: 381.2112.
1H, J¼10.4, 15.6 Hz), 6.70 (d, 1H, J¼15.6 Hz); 13C NMR (CDCl3,
75 MHz)
d
¼166.3, 134.5, 133.1, 131.7, 128.6, 127.6, 127.0, 126.3, 123.8,
123.6, 120.9, 120.2; MS (EI) m/z¼275 (Mþ, 18%), 129 (12), 128 (100),
115 (13), 104 (10), 77 (10), 76 (10), 50 (15); HRMS (m/z)¼275.0941,
calcd for C18H13NO2: 275.0946.
4.3.3. (Z)-Methyl
2-((E)-2-(1,3-dioxoisoindolin-2-yl)vinyl)-3-
(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)hept-2-enoate
4.2.9. 2-((1E,3E)-4-(p-Tolyl)buta-1,3-dien-1-yl)isoindoline-1,3-dione
(2i). Yellow solid, mp 125e126 ꢀC; Rf (50% EtOAc/hexane)¼0.45; IR,
nmax (KBr)¼3049, 3022, 2963, 2853,1731,1605,1509,1412,1261,1182,
(3c). Yellow oil; Rf (50% EtOAc/hexane)¼0.45; 1H NMR (CDCl3,
300 MHz)
d¼8.13 (d,1H, J¼15.2 Hz), 7.88e7.85 (m, 2H), 7.75e7.71 (m,
2H), 6.76 (d, 1H, J¼15.2 Hz), 3.87 (s, 3H), 2.18e2.11 (m, 2H), 1.36 (s,
1096 cmꢁ1
;
1H NMR (300 MHz, CDCl3):
d¼7.89e7.85 (m, 2H),
6H), 1.27 (s, 6H), 1.30e1.25 (m, 4H), 0.90e0.85 (t, 3H, J¼6.7 Hz); 13C
7.79e7.73 (m, 2H), 7.46e7.23 (m, 3H), 7.15e7.08 (m, 2H), 6.98 (d, 1H,
J¼14.5 Hz), 6.82e6.73 (dd,1H, J¼10.4,15.6 Hz), 6.65(d,1H, J¼15.6 Hz),
NMR (CDCl3, 75 MHz)
d
¼169.0,165.9,142.4,134.4,131.6,123.6,119.9,
117.6, 83.9, 51.7, 33.8, 31.7, 30.9, 29.4, 24.7, 24.6, 22.4,13.9; MS (EI) m/
z¼439 (Mþ, 5%), 421 (30), 394 (20), 353 (78), 339 (100), 294 (40), 250
(48), 238 (32), 163 (28), 147 (12), 130 (40), 119 (30), 105 (20), 76 (15),
55 (20). HRMS (m/z)¼439.2151, calcd for C24H30BNO6: 439.2166.
2.34 (s, 3H); 13C NMR (CDCl3, 75 MHz)
d
¼166.2, 137.5, 134.5, 133.1,
131.7, 129.4, 129.3, 126.2, 126.0, 123.6, 121.2, 119.7, 21.3; MS (EI) m/
z¼289 (Mþ,16%),143 (13),142 (100),141 (20),115 (15),104 (8), 76 (7),
50 (15); HRMS (m/z)¼289.1111, calcd for C19H15NO2: 289.1103.
4.4. Representative procedure for the Sonogashira coupling
of 1 with terminal alkynes
4.2.10. 2-((1E,3E)-4-(3-Fluorophenyl)buta-1,3-dien-1-yl)isoindoline-
1,3-dione (2j). Yellow needles, mp 139e140 ꢀC; Rf (50% EtOAc/
hexane)¼0.48; IR, nmax (KBr)¼3016, 1715, 1650, 1608, 1581,
PdCl2(PPh3)2 (3.5 mg, 5.0
mol) were mixed with EtOH (2 mL) in a glass vial equipped
with a screw cap. Diisopropylamine (140 L, 1.0 mmol) was added
mmol, 1 mol %) and CuI (4.8 mg,
1383 cmꢁ1
;
1H NMR (300 MHz, CDCl3):
d
¼7.90e7.86 (m, 2H),
25 m
7.78e7.74 (m, 2H), 7.42 (dd, 1H, J¼14.4, 10.6 Hz), 7.32e7.09 (m, 2H),
m
6.99 (d, 1H, J¼14.5 Hz), 6.95e6.89 (m, 3H), 6.65 (dd, 1H, J¼15.7,
and the vial was flushed with argon. (E)-N-(2-Iodovinyl)phthali-
mide 1 (150 mg, 0.50 mmol) and the appropriate acetylene
(0.55 mmol 1.1 equiv) were added and the mixture was stirred for
3 h. After the reaction was completed (GCeMS analysis) the vola-
tiles were evaporated under vacuum and the crude product was
chromatographed on silica gel (eluent: EtOAc in n-hexane 0e50%)
to afford the analytically pure products.
10.5 Hz); 13C NMR (CDCl3, 75 MHz)
d
¼166.1, 162.8 (d, J (13Ce19F)¼
245.3 Hz), 139.6 (d), 134.6, 131.7 (d), 130.0 (d), 128.6 (d), 123.6 (d),
122.2 (d, J (13Ce19F)¼2.4 Hz), 120.3 (d), 114.3 (d, J (13Ce19F)¼
21.7 Hz), 112.5 (d,
J
(
13Ce19F)¼21.7 Hz); 19F NMR (CDCl3,
282.3 MHz):
d
¼ꢁ113.93 (td, J¼9.7, 6.1 Hz); MS (EI) m/z¼293 (Mþ,
15%), 147 (12), 146 (100), 133 (14), 104 (17), 76 (26), 50 (16); HRMS
(m/z)¼293.0858, calcd for C18H12FNO2: 293.0852.
4.4.1. (E)-2-(4-Phenylbut-1-en-3-yn-1-yl)isoindoline-1,3-dione
(4a). Pale yellow solid, mp 114e115 ꢀC; Rf (50% EtOAc/hexane)¼
0.42; IR, nmax (KBr)¼3074, 3054, 2990, 2924, 2853, 2198, 1781, 1725,
4.3. Representative procedure for the SuzukieMiyaura cross-
coupling of 1 with ethylene-diboronic acid bis(pinacol) esters
1628, 1593, 1491, 1466, 1382, 1261, 1106 cmꢁ1 1H NMR (CDCl3,
;
To a solution of Pd(PPh3)4 (0.0167 mmol, 19.3 mg), (E)-N-(2-
iodovinyl)phthalimide 1 (0.334 mmol, 100 g), and the appropriate
ethylenediboronic acid bis(pinacol) ester (0.668 mmol) in toluene
(6.6 mL, 0.05 M) were added aqueous K2CO3 (1 mmol, 0.5 mL, 2 M)
300 MHz)
d
¼7.88e7.85 (m, 2H), 7.75e7.71 (m, 2H), 7.44e7.41 (m,
2H), 7.31e7.27 (m, 4H), 6.94 (d, 1H, J¼14.8 Hz); 13C NMR (CDCl3,
75 MHz)
d
¼165.8,134.8,131.5,131.4,128.3, 128.2, 127.8, 123.9, 123.2,
100.2, 92.1, 86.5; MS (EI) m/z¼273 (Mþ, 100%), 189 (10), 130 (10),

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P. Pawluc et al. / Tetrahedron 68 (2012) 3545e3551
3551
126 (20), 114 (12), 104 (10), 76 (15) 50 (20); HRMS calcd for
References and notes
C18H11NO2: 273.0790, found: 273.0798.
1. For recent reviews see: (a) Gopalaiah, K.; Kagan, H. B. Chem. Rev. 2011, 111,
4599e4657; (b) Carbery, D. R. Org. Biomol. Chem. 2008, 6, 3455e3460; (c)
Nugent, T. C.; El-Shazly, M. Adv. Synth. Catal. 2010, 353, 753e819; (d) Matsubara,
R.; Kobayashi, S. Acc. Chem. Res. 2008, 41, 292e301.
2. Uhr, H.; Boie, C.; Rieck, H.; Krueger, B.; Heinemann, U.; Market, R.; Vaupel, M.;
Kluger, M.; Stenzel, K.; Wachendorff-Neumann, U.; Mauler-Mchnick, A.; Kuck, K.;
Loesel, P.; Narabu, S. DE Patent 19918294, 2000; Chem. Abstr. 2000, 133, 309910.
3. Brown, A. D.; Bunnage, M. E.; Lane, C. A. L.; Lewthwaite, R. A.; Glossop, P. A.;
James, K.; Price, D. A. US 20,050,215,590, 2005; Chem. Abstr. 2005, 143, 346910.
4. Ogawa, T.; Yamada, H. JP 08176107, 1996; Chem. Abstr. 1996, 125, 221571.
5. (a) Goossen, L. J.; Blanchot, M.; Brinkmann, C.; Goossen, K.; Karch, R.; Rivas-
Nass, A. J. Org. Chem. 2006, 71, 9506e9509; (b) Goossen, L. J.; Rauhaus, J. E.;
Deng, G. Angew. Chem., Int. Ed. 2005, 44, 4042e4045.
4.4.2. (E)-2-(4-(Naphthalen-1-yl)but-1-en-3-yn-1-yl)isoindoline-
1,3-dione (4b). Pale yellow solid, mp 196 ꢀC; Rf (50% EtOAc/
hexane)¼0.43; IR, nmax (KBr)¼3054, 2959, 2929, 2873, 2859, 2137,
1727, 1581, 1503, 1462, 1390, 1287, 1267, 1122, 1073 cmꢁ1 1H NMR
;
(CDCl3, 300 MHz)
d
¼8.36 (m, 1H), 7.94e7.77 (m, 4H), 7.71e7.37 (m,
7H), 7.13 (d, 1H, J¼14.8 Hz); 13C NMR (CDCl3, 75 MHz)
¼165.8,
d
134.8, 133.2, 133.1, 131.5, 130.3, 128.7, 128.3, 127.8, 126.8, 126.4,
126.2, 125.3, 123.9, 120.9, 100.4, 91.4, 90.3; MS (EI) m/z¼323 (Mþ,
100%), 176 (15), 76 (10), 50 (5); HRMS calcd for C22H13NO2:
323.0946, found: 323.0947.
6. (a)Dehli, J.R.; Legros, J.;Bolm,C. Chem. Commun. 2005, 973e986; (b)Ogawa, T.;Kiji,
T.;Hayami, K.; Suzuki, H.Chem. Lett.1991,1443e1446;(c) Pan, X.; Cai, Q.; Ma, D. Org.
Lett. 2004, 6, 1809e1812; (d) Shen, R.; Porco, J. A., Jr. Org. Lett. 2000, 2, 1333e1336;
(e) Jiang, L.; Job, G. E.; Klapars, A.; Buchwald, S. L. Org. Lett. 2003, 5, 3667e3669.
7. Lam, P. Y. S.;Vincent, G.;Bonne,D.;Clark, C. G.Tetrahedron Lett. 2003, 44, 4927e4931.
8. Bolshan, Y.; Batey, R. A. Angew. Chem., Int. Ed. 2008, 47, 2109e2112.
9. Rogers, M. M.; Kotov, V.; Chatwichien, J.; Stahl, S. S. Org. Lett. 2007, 9, 4331e4334.
10. (a) Ziegler, C. B., Jr.; Heck, R. F. J. Org. Chem. 1978, 43, 2949e2952; (b) Har-
4.4.3. (E)-2-(4-(Trimethylsilyl)but-1-en-3-yn-1-yl)isoindoline-1,3-
dione (4c). Pale yellow solid, mp 121e122 ꢀC; Rf (50% EtOAc/
hexane)¼0.40; 1H NMR (CDCl3, 300 MHz)
¼7.90e7.87 (m, 2H),
d
7.78e7.75 (m, 2H), 7.23 (d, 1H, J¼15.4 Hz), 6.76 (d, 1H, J¼15.4 Hz),
0.21 (s, 9H); 13C NMR (CDCl3, 75 MHz)
d
¼165.7, 134.8, 131.5, 128.9,
€
rington, P. J.; Hegedus, L. S. J. Org. Chem. 1984, 49, 2657e2662; (c) Furstner, A.;
Mamane, V. Chem. Commun. 2003, 2112e2113; (d) Busacca, C. A.; Johnson, R. E.;
Swestock, J. J. Org. Chem. 1993, 58, 3299e3303; (e) Alacid, E.; Najera, C. Adv.
Synth. Catal. 2008, 350, 1316e1322.
123.9, 101.9, 99.9, 97.4, ꢁ0.1; MS (EI) m/z¼269 (Mþ, 25%), 254 (100),
227 (20), 102 (5), 50 (5); HRMS calcd for C15H15NO2Si: 269.0872,
found: 269.0862.
11. For selected examples, see: (a) McAlonan, H.; Murphy, J. P.; Nieuwenhuyzen,
M.; Reynolds, K.; Sarma, P. K. S.; Stevenson, P. J.; Thompson, N. J. Chem. Soc.,
Perkin Trans. 1 2002, 69e79; (b) Paredes, E.; Brasca, R.; Kneeteman, M.; Macini,
P. M. E. Tetrahedron 2007, 63, 3790e3799; (c) Tayama, E.; Sugai, S. Tetrahedron
Lett. 2007, 48, 6163e6166.
12. Tracey, M. R.; Hsung, R. P.; Antoline, J.; Kurtz, K. C. M.; Shen, L.; Slafer, B. W.;
Zhang, Y. Sci. Synth. 2005, 5, 387e475.
13. Mathieson, J. E.; Crawford, J. J.; Schmidtmann, M.; Marquez, R. Org. Biomol.
Chem. 2009, 7, 2170e2175.
14. Tsujita, H.; Ura, Y.; Matsuki, S.; Wada, K.; Mitsudo, T.; Kondo, T. Angew. Chem.,
Int. Ed. 2007, 46, 5160e5163.
15. Tanaka, R.; Hirano, S.; Urabe, H.; Sato, F. Org. Lett. 2003, 5, 67e70.
16. Gandon, V.; Aubert, C.; Malacria, M.; Vollhardt, K. P. C. Chem. Commun. 2008,
1599e1601.
17. (a) Burk, M. J.; Allen, J. G.; Kiesman, W. F.; Stoffan, K. M. Tetrahedron Lett. 1997,
38, 1309e1312; (b) Burk, M. J.; Allen, J. G.; Kiesman, W. F. J. Am. Chem. Soc. 1998,
120, 657e663.
4.4.4. (E)-2-(4-(1-(Trimethylsiloxy)cyclohexyl)but-1-en-3-yn-1-yl)
isoindoline-1,3-dione (4d). Pale yellow solid, mp 101e102 ꢀC; Rf
(50% EtOAc/hexane)¼0.49; 1H NMR (CDCl3, 300 MHz)
¼7.90e7.88
d
(m, 2H), 7.78e7.74 (m, 2H), 7.13 (d, 1H, J¼14.8 Hz), 6.80 (d, 1H,
J¼14.8 Hz), 1.95e1.25 (m, 10H), 0.20 (s, 9H); 13C NMR (CDCl3,
75 MHz)
d
¼165.8, 134.8, 131.4, 127.5, 123.9, 100.1, 96.3, 82.2, 77.2,
70.5, 41.2, 30.9, 25.2, 23.2, 2.0; MS (EI) m/z¼367 (Mþ, 10%), 352 (45),
338 (15), 324 (100), 278 (15), 207 (25); HRMS calcd for
C21H25NSiO3: 367.1604, found: 367.1588.
4.4.5. (E)-2-(Dec-1-en-3-yn-1-yl)isoindoline-1,3-dione
(4e). Pale
yellow solid, mp 184 ꢀC; Rf (50% EtOAc/hexane)¼0.42; 1H NMR
18. To the best of our knowledge, only two examples of 1-phthalimido-substituted
acyclic buta-1,3-dienesd1-(phthalimido)-buta-1,3-diene and 1,4-bis(phthalim
ido)-buta-1,3-diene have been reported: (a) Terada, A. Kogyo Kagaku Zasshi 1960,
81,1773e1776;(b)Yanagi, K.;Nishiyama, T. Nippon Kagaku Kaishi1978, 3, 404e411.
19. To the best of our knowledge, there are only two general protocols reported in the
(CDCl3, 300 MHz)
d
¼7.89e7.86 (m, 2H), 7.77e7.73 (m, 2H), 7.10 (d,
1H, J¼14.9 Hz), 6.76e7.69 (ddd, 1H, J¼14.9, 2.2, 2.2 Hz), 2.37e2.32
(m, 2H), 1.58e1.51 (m, 2H), 1.44e1.36 (m, 2H), 1.31e1.25 (m, 4H),
literature for the synthesis of (E)-b-iodoenamides based on copper-catalyzed io-
0.92e0.83 (m, 3H); 13C NMR (CDCl3, 75 MHz)
d
¼165.9, 134.6, 131.5,
dovinylation of amides with (E)-1,2-diiodoethene and iodovinylation of N-formyl
imides: (a) Sanapo, G. F.; Daoust, B. Tetrahedron Lett. 2008, 49, 4196e4199; (b) Pas-
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126.9, 123.7, 101.2, 93.5, 77.5, 31.4, 29.7, 28.7, 22.5, 19.6, 14.1; MS (EI)
m/z¼281 (Mþ, 20%), 252 (25), 239 (50), 212 (100), 182 (20), 134
(75); HRMS calcd for C18H19NO2: 281.1416, found: 281.1427.
21. Mulder, J. A.; Kurtz, K. C. M.; Hsung, R. P.; Coverdale, H.; Frederick, M. O.; Shen,
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4.4.6. (E)-2-(4-(4-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-
phenyl)but-1-en-3-yn-1-yl)isoindoline-1,3-dione (4f). Yellow solid,
mp 171e172 ꢀC; Rf (50% EtOAc/hexane)¼0.47; 1H NMR (CDCl3,
22. (a) Conreaux, D.; Bossharth, E.; Monteiro, N.; Desbordes, P.; Vors, J.-P.; Balme, G.
Org. Lett. 2007, 9, 271e274; (b) Ashley, E.; Cruz, E. G.; Stoltz, B. M. J. Am. Chem.
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23. (a) Diaz-Sanchez, B. R.; Iglesias-Arteaga, M. A.; Melgar-Fernandez, R.; Juaristi, E.
J. Org. Chem. 2007, 72, 4822e4825; (b) Kiewel, K.; Luo, Z.; Sulikowski, G. A. Org.
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300 MHz)
d
¼7.92e7.89 (m, 2H), 7.79e7.75 (m, 4H), 7.47e7.44 (m,
2H), 7.29 (d, 1H, J¼14.9 Hz), 6.98 (d, 1H, J¼14.9 Hz), 1.35 (s, 12H); 13C
NMR (CDCl3, 75 MHz)
d
¼165.8, 134.8, 134.6, 131.5, 130.6, 128.1,
24. For recent reviews see: (a) Marciniec, B. Acc. Chem. Res. 2007, 40, 943e952; (b)
125.9, 123.9, 100.1, 92.3, 87.9, 83.9, 29.7, 24.9; MS (EI) m/z¼399 (Mþ,
100%), 384 (10), 313 (17), 299 (15), 104 (5), 76 (6), 50 (4); HRMS
calcd for C24H22BNO4: 399.1642, found: 399.1629.
ꢀ
Pawluc, P.; Pruka1a, W.; Marciniec, B. Eur. J. Org. Chem. 2010, 219e229.
25. Marciniec, B.; Chadyniak, D.; Krompiec, S. Tetrahedron Lett. 2004, 45, 4065e4068.
ꢀ
26. (a) Pawluc, P.; Hreczycho, G.; Szudkowska, J.; Kubicki, M.; Marciniec, B. Org. Lett.
ꢀ
2009, 11, 3390e3393; (b) Pawluc, P.; Franczyk, A.; Walkowiak, J.; Hreczycho, G.;
Kubicki, M.; Marciniec, B. Org. Lett. 2011, 13, 1976e1979.
27. Recent applications of the NIS-mediated iododesilylation of substituted vinyl-
silanes: (a) Ilardi, E. A.; Stivala, C. E.; Zakarian, A. Org. Lett. 2008, 10, 1727e1730;
(b) Rodriguez-Escrich, C.; Urpi, F.; Vilarrasa, J. Org. Lett. 2008, 10, 5191e5194; (c)
Xie, Q.; Denton, R. W.; Parker, K. A. Org. Lett. 2008, 10, 5345e5348; (d) Herr-
mann, A. T.; Martinez, S. R.; Zakarian, A. Org. Lett. 2011, 13, 3636e3639.
28. No report in literature has been found on the halodesilylation of imido(amido)-
substituted vinylsilanes except the iododesilylation of b-silylvinyltoluene-sul-
fonamides: Timbart, L.; Cintrat, J.-C. Chem.dEur. J. 2002, 8, 1637e1640.
29. For details see Supplementary data.
Acknowledgements
Financial support from the Ministry of Science and Higher Ed-
ucation (Poland); Grant Iuventus Plus IP2010 031170 is gratefully
acknowledged.
30. (a) Suzuki, A. In; Negishi, E.-i., Ed. Handbook of Organopalladium Chemistry for
Organic Synthesis; Wiley-Interscience: New York, NY, 2002; Vol. 1, pp 249e262;
(b) Beller, M. Adv. Synth. Catal. 2009, 351, 3027e3043.
Supplementary data
31. For recent reviews see: (a) Sonogashira, K. In Metal-Catalyzed Cross-Coupling
Reactions; Stang, P. J., Diederich, F., Eds.; Wiley-VCH: Weinheim, 1998;
pp 203e229; (b) Viciu, M. S.; Nolan, S. P. In Modern Arylation Methods; Acker-
mann, L., Ed.; Wiley-VCH: Weinheim, 2009; Chapter 6, pp 183e220; (c) Chin-
chilla, R.; Najera, C. Chem. Rev. 2007, 107, 874e922.
NMR spectra of all compounds and crystallographic data for
compounds 1, 2b, 2h, 2j, and 4a. Supplementary data associated
with this article can be found, in the online version, at doi:10.1016/
j.tet.2012.03.012.