Nickel-catalyzed acylstannylation of 1,3-dienes: Synthesis and reaction of ε-oxoallylstannanes [3]

Full text of DOI:10.1021/ja0020409

9030
J. Am. Chem. Soc. 2000, 122, 9030-9031
Scheme 1
Nickel-Catalyzed Acylstannylation of 1,3-Dienes:
Synthesis and Reaction of E-Oxoallylstannanes
Eiji Shirakawa,*,† Yoshiaki Nakao,‡ Hiroto Yoshida,‡ and
Tamejiro Hiyama*,‡
Table 1. Nickel-Catalyzed Acylstannylation of 1,3-Dienesa
Graduate School of Materials Science
Japan AdVanced Institute of Science and Technology
Asahidai, Tatsunokuchi, Ishikawa 923-1292, Japan
Department of Material Chemistry
acylstannane
R1 R2
Me (1a)
1,3-diene
R3
time yield
(h) (%)b
prod(s),
entry
R4
3:4c
1
2
Ph
Ph
H
H (2a)
Me (2b)
Ph (2c) 48
0.2 72 3a
-
-
-
-
Graduate School of Engineering, Kyoto UniVersity
Me (1a) Me
Me (1a) Ph
Me (1a) -(CH2)4- (2d)
Me (1a) Me
2
73 3b
36 3c
45 3d
3d Ph
Sakyo-ku, Kyoto, 606-8501, Japan
4e Ph
24
5
6
7
8
Ph
Ph
Ph
Ph
H (2e)
H (2f)
H (2g)
H (2h)
Me (2b) 24
Me (2b)
Me (2b)
2
2
2
2
74 3e, 4e 33:67
68 3f, 4f 47:53
84 3g, 4g 44:56
86 3h, 4h 39:61
ReceiVed June 8, 2000
Me (1a) Ph
Me (1a) SiMe3
Me (1a) CH2SiMe3
Bu (1b) Me
Allylstannanes are one of the most versatile synthetic reagents
that react with electrophilic substrates such as carbonyl com-
pounds and organic halides to give a variety of olefinic products.1
Although unsubstituted allylstannanes are readily prepared by the
reaction between allyl/stannyl nucleophilic/electrophilic reagents,
no convenient and general methods are available for the synthesis
of functionalized allylstannanes. Here we report that the nickel-
catalyzed 1,4-acylstannylation of 1,3-dienes provides a convenient
method for the synthesis of allylstannanes having a carbonyl
group.2 To the best of our knowledge, this is the first example of
the transition metal-catalyzed carbometalation of 1,3-dienes at
their 1,4-positions except for the allylmagnesation of 1,3-dienes3
and the carbosilylation through three component coupling of 1,3-
dienes, disilanes and acyl chlorides.4
We first examined the reaction of benzoyl(trimethyl)tin (1a)
with 1,3-butadiene (2a) in the presence of a nickel complex and
found that PhCO and SnMe3 moieties in 1a were delivered to 2a
at its 1,4-positions. For example, treatment of 1a and 2a with 5
mol% of Ni(cod)2 in toluene at 50 °C for 10 min gave (Z)-1-
phenyl-5-trimethylstannyl-3-penten-1-one (3a)5 in 72% yield
(Scheme 1 and entry 1 of Table 1).6 2,3-Disubstituted 1,3-
butadienes 2b-d also reacted with 1a stereoselectively to give
the corresponding allylstannanes (entries 2-4). The addition of
1a to 2-substituted 1,3-dienes afforded corresponding products
as mixtures of regioisomers (entries 5-8). Propanoylstannane 1b
and 3-methyl-2-butenoylstannane 1c added to 2b, giving acyl-
stannylation products as a single isomer (entries 9 and 10),
whereas a mixture of stereoisomers was obtained in the reaction
of piperidinocarbonylstannane 1d (entry 11).
9e Et
56 3i
52 3j
73 3kf
-
-
-
10e Me2CdCH Bu (1c) Me
11 (CH2)5N Bu (1d) Me
2
2
a The reaction was carried out in toluene (0.3 mL) at 50 °C using
an acylstannane (0.23 mmol), a 1,3-diene (0.69 mmol) and Ni(cod)2
(11.5 µmol). b Isolated yield based on the organostannane. c Determined
by 119Sn NMR. d Reaction was carried out at 80 °C. e Reaction was
carried out at 70 °C. f A 87:13 mixture of (Z)- and (E)-isomers was
obtained.
lation of an acylstannane. The fraction of the decarbonylation
was less than 15% in such a nonpolar solvent as toluene or octane,
whereas a polar solvent DMF or THF predominantly caused the
decarbonylation to give trimethyl(phenyl)tin (5a) in more than
80% yield. In the absence of a 1,3-diene even in toluene, 1a
afforded 5a in 56% yield (eq 1).
The decarbonylation of 1a is attributed to oxidative addition
of 1a to the nickel(0) complex followed by deinsertion of carbon
monoxide from complex 6 and reductive elimination of 5a from
7 as illustrated in Scheme 2. This fact suggests that the
acylstannylation of 1,3-dienes should be initiated by the oxidative
addition to give 6, followed by insertion of a 1,3-diene to the
Ni-Sn bond in 6, affording π-allylnickel complex 8,7 which then
undergoes reductive elimination to give rise to 3 (Scheme 2).
Solvent was found to strikingly affect the selectivity of the
reaction of 1a with 2b: the acylstannylation versus decarbony-
† Japan Advanced Institute of Science and Technology.
‡ Kyoto University.
Scheme 2
(1) Davies, A. G. Organotin Chemistry; VCH: Weinheim, 1997.
(2) Transition metal-catalyzed carbostannylation of organostannanes towards
alkynes: (a) Shirakawa, E.; Yoshida, H.; Kurahashi, T.; Nakao, Y.; Hiyama,
T. J. Am. Chem. Soc. 1998, 120, 2975-2976. (b) Shirakawa, E.; Yoshida,
H.; Nakao, Y.; Hiyama, T. J. Am. Chem. Soc. 1999, 121, 4290-4291. (c)
Shirakawa, E.; Yamasaki, K.; Yoshida, H.; Hiyama, T. J. Am. Chem. Soc.
1999, 121, 10221-10222. (d) Shirakawa, E.; Yoshida, H.; Nakao, Y.; Hiyama,
T. Org. Lett. 2000, 2, 2209-2211.
(3) (a) Akutagawa, S.; Otsuka, S. J. Am. Chem. Soc. 1975, 97, 6870-
6871. (b) Barbot, F.; Miginiac, Ph. J. Organomet. Chem. 1978, 145, 269-
276.
(4) (a) Obora, Y.; Tsuji, Y.; Kawamura, T. J. Am. Chem. Soc. 1993, 115,
10414-10415. (b) Obora, Y.; Tsuji, Y.; Kawamura, T. J. Am. Chem. Soc.
1995, 117, 9814-9821.
(5) Configuration of the carbostannylation products was determined by NOE
1
in H NMR as is shown below.
(7) A similar catalytic cycle involving an anti-π-allylplatinum intermediate
generated by insertion of a 1,3-diene to a Pt-B bond is proposed in the
platinum-catalyzed diboration of 1,3-dienes. Ishiyama, T.; Yamamoto, M.;
Miyaura, N. Chem. Commun. 1996, 2073-2074.
(6) The reaction conditions are essentially identical with those used in the
nickel-catalyzed carbostannylation of alkynes, see ref 2c.
10.1021/ja0020409 CCC: $19.00 © 2000 American Chemical Society
Published on Web 09/01/2000

Communications to the Editor
J. Am. Chem. Soc., Vol. 122, No. 37, 2000 9031
Scheme 3
Scheme 4
Table 2. Addition of Allylstannanes to Aldehydes Mediated by
a
Bu2SnCl2
entry allylstannane R5 time (h) yield (%)b prod
E:Z
1
2
3
4
3a
3a
(Z)-3k
(E)-3k
i-Pr
Phc
i-Pr
i-Pr
3.5
3.5
2.0
2.0
67
76
98
11a
11b
11c >99:1
11c >99:1
87:13
89:11
Scheme 5
100
a The reaction was carried out at room temperature using an
allylstannane (0.30 mmol), an aldehyde (0.60 mmol) and Bu2SnCl2 (0.36
mmol). b Isolated yield based on the allylstannane. c Benzaldehyde (0.36
mmol) was used.
In the case of aminocarbonylstannane 1d, isomerization of
π-allylnickel complex 8 to 9 before reluctant reductive elimination
may cause coproduction of stereoisomer (E)-3k. The stannylnick-
elation pathway, as compared with an alternative carbonickelation
pathway, more likely explains the fact that the difference in the
acyl moieties largely affects the stereochemical results.
a mixture of R- and γ-adducts (41:59, 75% yield) for 13b.11 The
intramolecular oxygen-to-tin coordination in the reaction of (Z)-
3k should be responsible for high reactivity and high regiose-
lectivity, although the reason the reaction with acyl chlorides
showed the regiochemical result opposite from that with aldehydes
is not clear at present. The nucleophilic attack of 3b to benz-
aldehyde dimethyl acetal (15) activated by BF3-OEt2 proceeded
with exclusive γ-selectivity, affording syn- and anti-branched
ethers 16 in a ratio of 26:74.12
Combination of the acylstannylation of 1,3-dienes and allyl-
stannylation of alkynes should be a versatile method for the
preparation of alkenylstannanes having a functional group req-
uisite for further synthetic elaborations. Indeed, acylstannylation
product 3a derived from 1,3-diene 2a was allowed to add to ethyl
phenylpropiolate (17) in the presence of a palladium catalyst to
give acyldienylstannanes 18 and 19 in 85% yield (Scheme 5).2d
In conclusion, we have demonstrated that acylstannylation of
1,3-dienes proceeded in a high stereoselectivity in the presence
of a nickel catalyst. Furthermore, the resulting ꢀ-oxoallylstannanes
were transformed to various unconjugated enones in many ways
by virtue of the carbonyl group playing a significant role. Further
studies on the synthetic application of the reaction as well as
carbostannylations using various organostannanes and unsaturated
compounds are in progress in our laboratories.
The acylstannylated products are applicable to the synthesis
of various olefinic compounds by the reaction with diverse kinds
of electrophiles. The addition of allylstannane 3a to 2-methyl-
propanal (10a), after transmetalation with dibutyltin dichloride,
afforded homoallyl alcohol 11a in 67% yield, the carbon-carbon
bond formation occurring exclusively at the R-carbon of 3a
(Scheme 3 and entry 1 of Table 2), in striking contrast to
tributyl(crotyl)tin which upon the reaction with 10a gives an
87:13 mixture of R- and γ-adducts.8 The exclusive R-selectivity
observed with 3a should be ascribed to intramolecular coordina-
tion of the carbonyl group to the γ-tin atom, which stabilizes
intermediate 129 to induce the carbon-carbon bond formation
at the terminal carbon. 3a reacted also with benzaldehyde (10b)
to give linear homoallyl alcohol 11b in 76% yield (entry 2). It
is noteworthy that the carbonyl group in allylstannanes 3a
precisely controls the regioselectivity of the reaction. Both of
stereoisomers (Z)-3k and (E)-3k in combination with dibutyltin
dichloride reacted with 10a to afford 11c as a single isomer
(entries 3 and 4).10
Acknowledgment. We are grateful to Dr. Yasushi Nishihara, Tokyo
Institute of Technology, for the X-ray crystal structure analysis. We thank
Denkikagaku Kogyo Co., Ltd. for the generous gift of chloroprene.
In the presence of 10 mol% of dibutyltin dichloride, (Z)-3k
reacted with benzoyl chloride (13a) or phenylacetyl chloride (13b)
to give γ-acylated product regioselectively (Scheme 4), whereas
the corresponding reaction of tributyl(crotyl)tin with the aid of
15 mol% of Et4NCl is reported to provide no adduct for 13a or
Supporting Information Available: Detailed experimental proce-
dures including spectroscopic and analytical data (PDF). An X-ray
crystallographic file in CIF format. This material is available free of charge
via the Internet at http:/pubs.acs.org.
(8) Gambaro, A.; Ganis, P.; Marton, D.; Peruzzo, V.; Tagliavini, G. J.
Organomet. Chem. 1982, 231, 307-314.
(9) A similar intramolecular coordination of a carbonyl group to a tin atom
in â-stannyl ketones has been suggested. Ryu, I.; Nakahira, H.; Ikebe, M.;
Sonoda, N.; Yamato, S.; Komatsu, M. J. Am. Chem. Soc. 2000, 122, 1219-
1220.
JA0020409
(11) (a) Yano, K.; Baba, A.; Matsuda, H. Chem. Lett. 1991, 1181-1184.
(b) Yano, K.; Baba, A.; Matsuda, H. Bull. Chem. Soc. Jpn. 1992, 65, 66-70.
(12) The relative configuration was determined by an X-ray crystal structure
analysis of anti-16, see Supporting Information.
(10) Configuration of 11c was determined by NOE in a manner similar
to that depicted in ref 5.