Copper-catalyzed sequential alkyl/aryl or vinyl esterification of dicarboxylic acid anhydrides with alkoxysilanes

Article abstract of DOI:10.1021/jo100926a

(Figure presented) A copper(I)-catalyzed bis-esterification of cyclic anhydrides with aryl and vinyl alkoxysilanes is described, in which the alkoxy and aryl (or vinyl) esters of dicarboxylic acids were prepared in one pot with moderate to good yields. Notably, vinyl trimethoxysilanes also worked well with this procedure.

Full text of DOI:10.1021/jo100926a

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conditions. However, in these reactions, only the aryl moiety
Copper-Catalyzed Sequential Alkyl/Aryl or Vinyl
Esterification of Dicarboxylic Acid Anhydrides with
Alkoxysilanes
of aryl trialkoxysilane has been transferred to the organic
product and the alkoxyl moiety was discarded as waste,
which diminishes the atom-economy for such transforma-
tions. In 2006, Lerebours and Wolf reported that the meth-
oxy of phenyltrimethoxysilane was transferred to aldehyde
to form methyl benzoate (Scheme 1, eq 1).5 However, to the
best of our knowledge, examples of the transfers of both
the aryl and alkoxy moieties of the aryl trialkoxysilane have
never been reported. Recently, we developed a copper(II)-
catalyzed aromatic esterification reaction of carboxylic acid
with aryl and vinyl trialkoxysilanes (Scheme 1, eq 2).6 As part
of our continuing interest in the application of aryl trialkoxy-
silanes3a,7 and aryl trialkoxysilanes-mediated C-O bond-
forming reactions, we herein report a bis-esterification of
cyclic anhydrides with aryl trialkoxysilanes and vinyl trialk-
oxysilanes, in which the alkoxy and aryl (or vinyl) esters of
dicarboxylic acids are prepared in one pot (Scheme 1, eq 3).
Fang Luo,† Changduo Pan,‡ Pengcheng Qian,† and
Jiang Cheng*,†
†College of Chemistry & Materials Engineering,
Wenzhou University, Wenzhou 325000, People’s Republic of
China, and ‡Wenzhou Institute of Industry & Science,
Wenzhou 325000, People’s Republic of China
jiangcheng@wzu.edu.cn
Received May 13, 2010
SCHEME 1. The Esterification Reaction with Aryl
Trimethoxysilane
A copper(I)-catalyzed bis-esterification of cyclic anhy-
drides with aryl and vinyl alkoxysilanes is described, in
which the alkoxy and aryl (or vinyl) esters of dicarboxylic
acids were prepared in one pot with moderate to good
yields. Notably, vinyl trimethoxysilanes also worked well
with this procedure.
Initial studies were performed by using the reaction of
phthalic anhydride with phenyl trimethoxysilane as the
model reaction, employing Cu(OAc)2 as the catalyst at 130 °C
(Table 1). Considering that the C-Si bond generally needs a
fluoro source for activation, we first focused on fluoro source
screening and found that AgF showed good activity (Table 1,
entry 6). A profound solvent effect was observed and non-
polar toluene was found to be superior to other solvents. The
source of copper in the reactions also had dramatic effects on
the reaction. CuBr was the best reagent, leading to 87%
isolated yield of the desired product (Table 1, entry 11). In
addition, GC-MS was conducted when using Cu(OAc)2
Aryl trialkoxysilanes have been widely used as significant
transmetalation reagents for the formation of C-C,1,2
C-N,3 and C-S bonds4 because of their low cost, easy avail-
ability, nontoxic byproducts, and stability under many reaction
(1) For reviews on the Hiyama reaction, see: (a) Hiyama, T. In Metal-
Catalyzed Cross-Coupling Reactions; Diederich, F., Stang, P. J., Eds.; Wiley-
VCH: New York, 1998; Chapter 10. (b) Hiyama, T. J. Organomet. Chem. 2002,
653, 58. (c) Denmark, S. E.; Baird, J. D. Chem.;Eur. J. 2006, 12, 4954.
(d) Strotman, N. A.; Sommer, S.; Fu, G. C. Angew. Chem., Int. Ed. 2007, 46,
3556. (e) Handy, C. J.; Manoso, A. S.; McElroy, W. T.; Seganish, W. M.; DeShong,
P. Tetrahedron 2005, 61, 12201.
(2) For selected references, see: (a) Dai, X.; Strotman, N. A.; Fu, G. C.
J. Am. Chem. Soc. 2008, 130, 3302. (b) Shi, S. Y.; Zhang, Y. H. J. Org. Chem.
2007, 72, 5927. (c) Seganish, W. M.; DeShong, P. Org. Lett. 2006, 8, 3951.
(d) Dey, R.; Chattopadhyay, K.; Ranu, B. C. J. Org. Chem. 2008, 73, 9461.
(e) So, C. M.; Lee, H. W.; Lau, C. P.; Kwong, F. Y. Org. Lett. 2009, 11, 317.
(f) Zhang, L.; Qing, J.; Yang, P.; Wu, J. Org. Lett. 2008, 10, 4971. (g) Zhang,
L.; Wu, J. J. Am. Chem. Soc. 2008, 130, 12250. (h) Lerebours, R.; Wolf, C.
Org. Lett. 2007, 9, 2737. (i) Oi, S.; Taira, A.; Honma, Y.; Inoue, Y. Org. Lett.
2003, 5, 97. (j) Denmark, S. E.; Amishiro, N. J. Org. Chem. 2003, 68, 6997.
(k) Tomita, D.; Wada, R.; Kanai, M.; Shibasaki, M. J. Am. Chem. Soc. 2005,
127, 4138. (l) Oi, S.; Taira, A.; Honma, Y.; Sato, T.; Inoue, Y. Tetrahedron:
Asymmetry 2006, 17, 598. (m) Hargrave, J. D.; Herbert, J.; Bish, G.; Frost,
C. G. Org. Biomol. Chem. 2006, 4, 3235. (n) Koike, T.; Du, X.; Sanada, T.;
Danda, Y.; Mori, A. Angew. Chem., Int. Ed. 2003, 42, 89. (o) Oi, S.; Honma,
Y.; Inoue, Y. Org. Lett. 2002, 4, 667. (p) Yang, S.; Li, B.; Wan, X.; Shi, Z.
J. Am. Chem. Soc. 2007, 129, 6066. (q) Zhou, H.; Xu, Y.-H.; Chung, W.-J.;
Loh, T.-P. Angew. Chem., Int. Ed. 2009, 48, 5355. (r) Hachiya, H.; Hirano,
K.; Satoh, T.; Miura, M. Angew. Chem., Int. Ed. 2010, 49, 2202.
(3) (a) Lin, B.; Liu, M.; Ye, Z.; Ding, J.; Wu, H.; Cheng, J. Org. Biomol.
Chem. 2009, 7, 869. (b) Song, R.-J.; Deng, C.-L.; Xie, Y.-X.; Li, J.-H.
Tetrahedron Lett. 2007, 48, 7845. (c) Lam, P. Y. S.; Deudon, S.; Averill,
K. M.; Li, R.; He, M. Y.; DeShong, P.; Clark, C. G. J. Am. Chem. Soc. 2000,
122, 7600. (d) Lam, P. Y. S.; Deudon, S.; Hauptman, E.; Clark, C. G.
Tetrahedron Lett. 2001, 42, 2427.
(4) Luo, P.-S.; Yu, M.; Tang, R.-Y.; Zhong, P.; Li, J.-H. Tetrahedron
Lett. 2009, 50, 1066.
(5) Lerebours, R.; Wolf, C. J. Am. Chem. Soc. 2006, 128, 13052.
(6) Luo, F.; Pan, C.; Qian, P.; Cheng, J. Synthesis 2010, 2005.
(7) (a) Lin, B.; Liu, M.; Ye, Z.; Zhang, Q.; Cheng, J. Tetrahedron Lett.
2009, 50, 1714. (b) Ye, Z.; Chen, F.; Luo, F.; Wang, W.; Lin, B.; Jia, X.;
Cheng, J. Synlett 2009, 2198. (c) Ye, Z.; Liu, M.; Lin, B.; Wu, H.; Ding, J.;
Cheng, J. Tetrahedron Lett. 2009, 50, 530. (d) Pan, C.; Liu, M.; Zhao, L.; Wu,
H.; Ding, J.; Cheng, J. Catal. Commun. 2008, 9, 1685.
DOI: 10.1021/jo100926a
r
Published on Web 06/30/2010
J. Org. Chem. 2010, 75, 5379–5381 5379
2010 American Chemical Society

Luo et al.
JOCNote
TABLE 1. Selected Results of Screening the Optimal Conditionsa
TABLE 2. Copper(I)-Catalyzed Esterification Reaction of Anhydride
with Phenyl and Napthalenyl Trimethoxysilanesa
entry
Cu source
additive
solvent
toluene
yield (%)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
CuBr
CuBr2
CuSO4
Cu(acac)2
Cu2O
CuO
TBAF 3H2O
3
<5
<5
<5
10
<5
55
30
20
40b
15b
87
39
50
58
85
8
KF
toluene
toluene
toluene
toluene
toluene
DMSO
NMP
ClCH2CH2Cl
CH3CN
toluene
toluene
toluene
toluene
toluene
toluene
toluene
toluene
toluene
toluene
CsF
FeF3
CuF2
AgF
AgF
AgF
AgF
AgF
AgF
AgF
AgF
AgF
AgF
AgF
AgF
AgF
AgF
AgF
CuI
CuF2
CuCl
63
67
47
0
aReaction conditions: phthalic anhydride 1 (0.2 mmol), PhSi(OMe)3
2 (0.3mmol), Cusource (20 mol%), additive (3equiv), drysolvent(2mL),
130 °C, 30 h. b80 °C
as catalyst. No acetyloxylation product was detected. The
blank experiment confirmed that in the absence of the
copper salts, no desired product was formed (Table 1, entry
20). A compatible yield was obtained when the process
was conducted under an inert atmosphere or oxygen. The
result shows that oxygen is not required for this transfor-
mation.
Encouraged by these results, we further pursued the scope
of the process with respect to the other substrates. As ex-
pected, a series of anhydrides worked well under the reaction
conditions (Table 2). Arene dicarboxylic acid anhydrides
coupled efficiently with phenyl trimethoxysilane, and good
yields were obtained (Table 2, entries 1 and 2). It is worth
noting that aliphatic and unsaturated dicarboxylic acid an-
hydrides were also good reaction partners (Table 2, entries
3-7). However, steric hindrance of dicarboxylic acid anhyd-
rides had little effect on the reaction. For example, 3gb was iso-
lated in 42% yield (Table 2, entry 7). Homophthalic anhy-
dride was subjected to the standard reaction conditions.
However, a complex mixture was obtained. Importantly,
the rigorous exclusion of air/moisture was not required in
any of these transformations, a condition that represents an
exceedingly practical alternative method for the synthesis of
esters. When this reaction was conducted on a 1 mmol scale,
the desired product 3aa was formed in a satisfactory 72%
yield.
Having demonstrated the utility of the optimized condi-
tions on phenyl and 1-naphthalenyl trimethoxysilanes, we
turned our attention to the scope of aryl trimethoxysilanes.
As expected, a series of aryl alkoxysilanes reacted smoothly,
providing esters in moderate to good yields (Table 3). It is
worth pointing out that vinyl was tolerated under the standard
procedure. As far as 2f and 2g were concerned, both the vinyl
and alkoxy moieties were transferred to the product, while the
aReaction conditions: 1 (0.2 mmol), 2 (0.3 mmol), CuBr (20 mol %),
AgF (3 equiv), dry toluene (2 mL), 130 °C, 30 h.
methyl moiety remained untouched (Table 3, entries 5 and 6).
The direct addition of carboxylic acids to terminal alkynes
catalyzed by Hg,8 Ru,9 Rh,10 or Ir11 is a straightforward and
atom-economical process for the synthesis of enol esters.
However, the use of toxic mercury salts or expensive cata-
lysts has greatly diminished the scope of the aforementioned
procedure. Thus, our procedure represents a practical alter-
native method to access vinyl esters.
(8) Hudrlik, P. F.; Hudrlik, A. M. J. Org. Chem. 1973, 38, 4254.
(9) (a) Kawano, H.; Masaki, Y.; Matsunaga, T.; Hiraki, K.; Onishi, M.;
Tsubomura, T. J. Orgnomet. Chem. 2000, 604, 69. (b) Bruneau, C.; Dixneuf,
P. H. Chem. Commun. 1997, 507. (c) Doucet, H.; Martin-Vaca, B.; Bruneau,
C.; Dixneuf, P. H. J. Org. Chem. 1995, 60, 7247. (d) Rotem, M.; Shvo, Y.
Organometallics 1983, 2, 1689.
(10) (a) Lu, X.; Zhu, G.; Ma, S. Tetrahedron Lett. 1992, 33, 7205.
(b) Bianchini, C.; Meli, A.; Peruzzini, M.; Zanobini, F.; Bruneau, C.;
Dixneuf, P. H. Organometallics 1990, 9, 1155.
(11) Nakagawa, H.; Okimoto, Y.; Sakaguchi, S.; Ishii, Y. Tetrahedron
Lett. 2003, 44, 103.
5380 J. Org. Chem. Vol. 75, No. 15, 2010

Luo et al.
JOCNote
TABLE 3. Copper(I)-Catalyzed Esterification Reaction of Phthalic
SCHEME 2. Reaction of Acyclic Anhydride with Vinyl Tri-
methoxysilane
Anhydride with Aryl and Vinyl Trimethoxysilanea
the reaction of anhydride and silicon alkoxide (Figure 1),12
may be the key intermediate for this transformation.
FIGURE 1. Plausible intermediate.
In conclusion, we have developed a novel esterification of
dicarboxylic acid anhydrides with the readily prepared aryl
and vinyl trimethoxysilanes. The procedure transfers both
alkoxyl and aryl moieties to the esterification products in one
pot, and represents a novel and atom-economical method for
the synthesis of dicarboxylic esters.
Experimental Section
General Procedure for the Esterification Reaction of Anhy-
dride with Trialkoxysilane. Under air, a sealed tube was charged
with anhydride (0.2 mmol), silane reagent (0.3 mmol), CuBr
(5.7 mg, 20 mol %), AgF (75.5 mg, 0.6 mmol), and dry toluene
(2 mL). The mixture was stirred at 130 °C. After the completion
of the reaction, the solvent was evaporated under reduced
pressure and the residue was purified by flash column chromato-
graphy on silica gel to give the desired product.
Methyl naphthalen-1-yl phthalate (3ab): 1H NMR (CDCl3,
300 MHz) δ 8.10-8.00 (m, 2H), 7.91-7.89 (m, 3H), 7.86-7.79
(m, 2H), 7.69-7.52 (m, 4H), 3.90 (s, 3H); 13C NMR (CDCl3, 125
MHz) δ 167.9, 165.9, 146.8, 134.7, 132.6, 131.8, 131.3, 131.2,
129.4, 129.2, 128.0, 126.8, 126.53, 126.50, 126.2, 125.5, 121.3,
117.9, 52.8; IR (prism, cm-1) ν 2930, 2159, 1727, 1223, 1110,
1054; HRMS (EI) calcd for C19H15O4 (M þ H)þ 307.0970,
found 307.0962.
aReaction conditions: 1a (0.2 mmol), 2 (0.3 mmol), CuBr (20 mol %),
AgF (3 equiv), dry toluene (2 mL), 130 °C, 30 h.
The acyclic anhydride 4-methoxy benzoic anhydride and
vinyl trimethoxysilane were subjected to the procedure, and
methyl 4-methoxybenzoate and vinyl 4-methoxybenzoate
were isolated in equal amounts (Scheme 2).
Under the standard reaction condition, the formation of
methyl 4-methoxybenzoate was confirmed by GC-MS in the
absence of CuBr. The silyl carboxylate A, which derived from
Acknowledgment. We thank the National Natural Science
Foundation of China (No. 20972115) and the Key Project of
Chinese Ministry of Education (No. 209054) for financial
support.
Supporting Information Available: Experimental proce-
dures along with copies of spectra. This material is available
free of charge via the Internet at http://pubs.acs.org.
(12) (a) Post, H. W.; Hofrichter, C. H., Jr. J. Org. Chem. 1940, 5, 443.
(b) Narain, R. P.; Mehrotra, R. C. J. Indian Chem. Soc. 1964, 41, 755.
J. Org. Chem. Vol. 75, No. 15, 2010 5381