Conversion of acid chloride into homoallylic alcohol via allylic C-H bond activation of alkene with a zirconocene complex [16]

Full text of DOI:10.1021/ja0167194

J. Am. Chem. Soc. 2001, 123, 12115-12116
12115
Conversion of Acid Chloride into Homoallylic
Scheme 1
Alcohol via Allylic C-H Bond Activation of Alkene
with a Zirconocene Complex
Kazuya Fujita, Hideki Yorimitsu, Hiroshi Shinokubo,
Seijiro Matsubara, and Koichiro Oshima*
Department of Material Chemistry
Graduate School of Engineering
Kyoto UniVersity, Yoshida
Table 1. Reaction of 1a with Various Acid Chlorides
Sakyo-ku, Kyoto 606-8501, Japan
ReceiVed July 27, 2001
ReVised Manuscript ReceiVed October 9, 2001
2
Zirconocene-alkene complexes [Cp Zr(alkene)], generated in
situ by thermolysis of dialkylzirconocene, have been widely used
in organic synthesis. The complexes are transformed into zir-
conacycles via oxidative coupling with another carbon-carbon
Scheme 2
1
multiple bond. Additionally, coupling reaction with aldehydes
or ketones affords the corresponding saturated alcohols via the
oxazirconacyclopentane intermediate.2 However, reaction of
Cp
2
Zr(alkene) with acid halide has not been explored. During
the course of our study on reactions mediated by zirconocene
3
2
complexes, we found that Cp Zr(alkene) 1, prepared at 0 °C,
reacted with acid chloride 2 to give homoallylic alcohol 3. The
formation of the alcohol apparently involved allylic C-H bond
activation of the coordinating alkene. Here we wish to disclose
our preliminary result of study on this reaction.
2 2
Cp ZrCl (2 mmol) was treated with n-BuMgBr (1 M THF
solution, 4 mL, 4 mmol) in benzene (20 mL) with cooling in an
ice/water bath. After the reaction mixture was stirred at 0 °C for
Scheme 3
Scheme 4
30 min, benzoyl chloride (2a, 1 mmol) was added. The whole
mixture was stirred for 3 h at 0 °C. Usual workup followed by
silica gel column purification afforded 3aa in 82% yield (Scheme
4
1
). Pentyl-, octyl-, and 3-phenylpropylmagnesium bromide,
instead of butylmagnesium bromide, were also effective to yield
5
the corresponding homoallylic alcohols.
Reaction with other aromatic acid chlorides is summarized in
Table 1. Most of the reactions proceeded in satisfactory yields,
although electron-rich acid chlorides such as 2e resulted in lower
yields. In contrast to the reaction with aromatic acid chloride,
upon treatment of octanoyl chloride with 1a, cyclopropanol 4 was
6
obtained in 25% yield, in addition to 3ag (Scheme 2). More
interestingly, reaction with methyl benzoate, instead of benzoyl
chloride, cleanly furnished cyclopropanol 5 in 85% yield. It is
also worth noting that addition of PPh Me as an additive to the
2
reaction of 2a gave rise to formation of 5 without contamination
of 3aa.
We are tempted to assume the reaction mechanism for the
formation of homoallylic alcohol as depicted in Scheme 3. There
2
exists an equilibrium between Cp Zr(1-butene) and zirconocene
crotyl hydride [6a, Cp Zr(crotyl)H] according to the literature of
2
7,8
Harrod. Hydride attack on benzoyl chloride followed by
allylation furnishes 3aa. The following experiments suggest the
order of the sequential nucleophilic attack (Scheme 4). Reaction
of benzaldehyde with the crotylzirconium reagent, prepared from
(
1) (a) Negishi, E.; Takahashi, T. Acc. Chem. Res. 1994, 27, 124-130. (b)
Negishi, E.; Takahashi, T. Bull. Chem. Soc. Jpn. 1998, 71, 755-769. (c)
Takahashi, T.; Kotora, M.; Hara, R.; Xi, Z. Bull. Chem. Soc. Jpn. 1999, 72,
591-2602.
2
2 2
Cp ZrCl and a crotyl Grignard reagent, yielded 3aa with anti
(
2) (a) Takahashi, T.; Suzuki, N.; Hasegawa, M.; Nitto, Y.; Aoyagi, K.;
Saburi, M. Chem. Lett. 1992, 331-334. (b) Suzuki, N.; Rousset, C. J.; Aoyagi,
selectivity (syn/anti ) 27/73). The selectivity was similar to that
observed in the reaction in Scheme 1. On the other hand, treatment
of ketone 7 with Schwartz reagent led to a slight syn selectivity.
Preparations of the requisite Grignard reagents are laborious.
K.; Kotora, M.; Takahashi, T. J. Organomet. Chem. 1994, 473, 117-128.
(
3) Fujita, K.; Nakamura, T.; Yorimitsu, H.; Oshima, K. J. Am. Chem. Soc.
2
001, 123, 3137-3138.
(4) Traces of benzyl alcohol and the saturated analogue of 3aa were
detectable byproducts in the crude oil. Other conceivable byproducts such as
tertiary alcohol, generated via double allylation, were not observed at all.
Next, we investigated direct preparation of Cp
from Cp ZrCl and alkene. Zirconocene dichloride (2 mmol) was
2
Zr(2-alkenyl)H
(
5) The use of THF as a solvent, instead of benzene, decreased the yield
2
2
of 3 (3aa: 80%, 3da: 76%).
treated with cyclopentylmagnesium bromide (4 mmol) in the
(
6) Titanium-alkene complexes effected formation of cyclopropanols: (a)
Lee, J.; Kim, H.; Cha, J. K. J. Am. Chem. Soc. 1995, 117, 9919-9920. (b)
(7) Dioumaev, V. K.; Harrod, J. F. Organometallics 1997, 16, 1452-1464.
Also see, Negishi, E.; Maye, J. P.; Choueiry, D. Tetrahedron 1995, 51, 4447-
Kasatkin, A.; Nakagawa, T.; Okamoto, S.; Sato, F. J. Am. Chem. Soc. 1995,
17, 3881-3882. (c) Kulinkovich, O. G.; Sviridov. S. V.; Vasilevski, D. A.
1
4462.
2
Synthesis 1991, 234. (d) Corey, E. J.; Rao, S. A.; Noe, M. C. J. Am. Chem.
Soc. 1994, 116, 9345-9346. (e) Kulinkovich, O. G.; de Meijere, A. Chem.
ReV. 2000, 100, 2789-2834.
(8) Photolysis of Fe(CO)
4
(η -CH
2
dCHCH
3
) resulted in similar rearrange-
ment: Barnhart, T. M.; McMahon, R. J. J. Am. Chem. Soc. 1992, 114, 5434-
5435.
1
0.1021/ja0167194 CCC: $20.00 © 2001 American Chemical Society
Published on Web 11/08/2001

12116 J. Am. Chem. Soc., Vol. 123, No. 48, 2001
Communications to the Editor
Scheme 5
Scheme 6
is again crucial for the successful formation of homoallylic
alcohols. Alcohol 3ba was formed in 46% yield in the reaction
without benzene. The results were comparable to those obtained
by Method A (Table 2, Method B). Advantageously, ester and
amide moieties could survive under the reaction conditions (entries
12 and 13). Alkenes are much more readily available than the
corresponding allylic magnesium reagents. Thus, this method
promises rapid synthesis of a wide spectrum of homoallylic
alcohols.
Table 2. Direct Synthesis of Homoallylic Alcohols from Alkenes
The allylic C-H bond cleavage as shown in Scheme 3 was
further confirmed by employing 3,3-dideuterio-1-octene (9).
Zirconium complex 10 was prepared from 9 by Method B, and
benzoyl chloride was added to 10 to afford deuterated homoallylic
alcohol 11 (Scheme 6).
In summary, we have found a new divergent route to homo-
allylic alcohols, utilizing the allylic C-H bond activation of
alkenes. Reaction of an allylic halide/metal or an allylic metal
with aldehyde is a standard procedure to obtain homoallylic
alcohol. Direct formation of allylic metals from alkenes employs
1
2
highly basic and nucleophilic organolithium reagents. As far as
zirconium compounds are concerned, allylic zirconium reagents
have been prepared from low-valent zirconocene and alkenes that
13
have good leaving groups such as alkoxide at the allylic position.
In contrast, the present methodology requires easy-handling and
readily available alkenes, instead of reactive allylic halides, and
saves tasks in preparing allylic halides. The Cp Zr(alkene)-
2
mediated allylation offers mild and efficient synthesis of homo-
allylic alcohols. Moreover, this reaction will develop novel utility
2
of the Cp Zr(alkene) reagent.
Acknowledgment. This work was supported by Grants-in-Aid for
Scientific Research (Nos. 12305058 and 10208208) from the Ministry
of Education, Culture, Sports, Science and Technology, Government of
Japan. H.Y. acknowledges JSPS for financial support.
Supporting Information Available: Experimental details and char-
acterization data (PDF). This material is available free of charge via the
Internet at http://pubs.acs.org.
presence of 1-pentene (6 mmol) in benzene (20 mL) at 0 °C for
3
0 min and at 25 °C for an additional 1 h (Scheme 5, Method
A). Initially formed Cp Zr(cyclopentene) 8 was anticipated to
undergo ligand exchange, forming Cp
JA0167194
2
9
2
Zr(1-pentene). This was
(11) (a) Miura, K.; Funatsu, M.; Saito, H.; Ito, H.; Hosomi, A. Tetrahedron
indeed the case, and 3ba was obtained in 76% yield upon
treatment of benzoyl chloride with the reagent at 0 °C (Table 2,
entry 1). Other alkenes could participate in the ligand exchange
to furnish the corresponding homoallylic alcohols (Table 2,
Method A).10
Lett. 1996, 37, 9059-9062. (b) Negishi, E.; Holmes, S. J.; Tour, J. M.; Miller,
J. A. J. Am. Chem. Soc. 1985, 107, 2568-2569. (c) Thanedar, S.; Farona, M.
F. J. Organomet. Chem. 1982, 235, 65-68.
(12) From simple alkene: (a) Heus-Kloos, Y. A.; de Jong, R. L. P.;
Verkruijsse, H. D.; Brandsma, L.; Julia, S. Synthesis 1985, 958-959. (b)
Akiyama, S.; Hooz, J. Tetrahedron Lett. 1973, 14, 4115-4118. From alkene
having a metal-directing group: (c) Hoppe, D.; Hense, T. Angew. Chem., Int.
Ed. Engl. 1997, 36, 2282-2316. (d) Prasad, K. R. K.; Hoppe, D. Synlett 2000,
2 2
Furthermore, reduction of Cp ZrCl with Mg metal in the
11
presence of alkene also provided the reagent 6. In this method,
1
067-1069. (e) Pippel, D. J.; Weisenberger, G. A.; Faibish, N. C.; Beak, P.
addition of benzene as a cosolvent prior to reaction with PhCOCl
J. Am. Chem. Soc. 2001, 123, 4919-4927.
(13) (a) Ito, H.; Taguchi, T.; Hanzawa, Y. Tetrahedron Lett. 1992, 33,
(
9) A similar ligand exchange reaction of a titanium reagent was reported:
1295-1298. (b) Ito, H.; Nakamura, T.; Taguchi, T.; Hanzawa, Y. Tetrahedron
1995, 51, 4507-4518. (c) Hanzawa, Y.; Ito, H.; Taguchi, T. Synlett 1995,
299-305. (d) Ito, H.; Kuroi, H.; Ding, H.; Taguchi, T. J. Am. Chem. Soc.
1998, 120, 6623-6624. (e) Rousset, C. J.; Swanson, D. R.; Lamaty, F.;
Negishi, E. Tetrahedron Lett. 1989, 30, 5105-5108.
Lee, J.; Kim, H.; Cha, J. K. J. Am. Chem. Soc. 1996, 118, 4198-4199. Also
see ref 6a.
(
10) The reaction in THF itself resulted in the diminished yields of 3. For
instance, 3ea was obtained in 26% yield along with benzyl alcohol (17%).