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Indium-mediated allylation of aryl trichloromethyl ketones in aqueous media
Chinese Chemical Letters 18 (2007) 1061–1063 www.elsevier.com/locate/cclet
Indium-mediated allylation of aryl trichloromethyl ketones in aqueous media Zhi Jian Bao, Jun Lu, Shun Jun Ji * Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry and Chemical Engineering, Suzhou (Soochow) University, Suzhou 215123, China Received 14 May 2007
Abstract It is described that indium-mediated allylation of trichloromethyl ketones could afford the corresponding homoallylic alcohols smoothly in aqueous media. # 2007 Shun Jun Ji. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. Keywords: Indium; Trichloromethyl ketone; Allylation; Aqueous media
The development of Barbier-type carbon–carbon bond formations could offer tremendous opportunities in synthetic organic chemistry. This is because homoallylic alcohols are versatile intermediates that can be converted to a wide variety of synthetically useful compounds [1]. Up to now, many metals have been used in the allylation, such as Sn [2], Zn [3], Mg [4], and Cd [5]. In recent years, the chemistry of indium has become more popular in organic synthesis. Indium has also been performed in water or aqueous solvent systems in order to minimize the use of hazardous solvents. Indium metal for Barbier-type reaction has been reported several times [6]. In spite of the application in synthesis, little is known about the allylation of ketones. Because the activity of ketones are so poor that they can hardly reacted with allyl halid, especially the activity of trihalogenmethyl ketones is poorer to be reacted. To the best of our knowledge, there was no report for the allylation of trihalogenmethyl ketones in aqueous media. Moreover, trihalogenmethyl compounds are important intermediates in organic synthesis. They can be converted to medicines for the treatment of AIDS [7], aminophenol [8], alkenes [9], alkynes [10], etc. Therefore, we hope to achieve allylation of trihalogenmethyl ketones. In this paper, we report the allylation reaction of aryl trichloromethyl ketones using In/InCl3/NH4Cl (sat.)/THF as the reaction system. It is a new, efficient synthetic method for the allylation reaction of trichloromethyl ketones (Scheme 1). In our initial studies, the In-mediated allylation reaction of trichloromethyl phenyl ketone with allyl bromide was carried out in THF, but no product was found. Therefore, saturated NH4Cl solution was introduced to enhance the reaction, the desired product could be obtained, whereas the product was obtained in low yield (30%). Some other Lewis acids were also chosen to enhance the reaction. To our delight, the product could be obtained in good yield
* Corresponding author. E-mail address: [email protected] (S.J. Ji). 1001-8417/$ – see front matter # 2007 Shun Jun Ji. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. doi:10.1016/j.cclet.2007.07.035
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Scheme 1. Table 1 Optimization of the reaction conditions Entry
Systema
Time (h)
Yield (%)
1 2 3 4 5 6 7
THF InCl3 + THF ITHF + NH4Cl (sat.) THF + HCl (0.1N) In(OTf)3 + THF + NH4Cl (sat.) H2O + EtOH THF + InCl3 + NH4Cl (sat.)
24 24 24 24 24 24 6
N.R. N.R. 30 16 58 50 72
a
THF (1 mL), InCl3/In(OTf)3 (0.1 equiv.), NH4Cl(sat.)/EtOH/HCl (4 mL), H2O (1 mL).
Table 2 Allylation of aryl trichloromethyl ketones with allyl bromide Entry
Ar
Product
Time (h)
Yielda (%)
1 2 3 4 5 6 7 8
C6H5 4-ClC6H4 4-MeOC6H4 3-MeOC6H4 4-MeC6H4 1-Naphthyl 2-Naphthyl 2-Thiophene
3a 3b 3c 3d 3e 3f 3g 3h
6 20 4 4 5 6 6 20
72 78 68 58 72 40 74 63
a
Isolated yields.
(72%) when InCl3 (10 mmol%) was added to the reaction system. Lower yields were found when other reaction systems were used. The results obtained were shown in Table 1. Having optimized the reaction conditions, we extended the indium-mediated allylation to a wide variety of trichloromethyl ketones. The generality and scope of the reaction was summarized in Table 2. All products were characterized by IR, 1H NMR, and EA or MS. As was seen from Table 2, trichloromethyl ketones carrying either electron-donating or electron-withdrawing substituents could react to afford the homoallylic alcohols in moderate to good yields. The heteroaromatic ketones also could be afforded the corresponding homoallylic alcohols. General procedure. A 25 mL RBF was charged with 2,2,2-trichloro-1-phenylethanone (223 mg, 1 mmol), allyl bromide(182 mg, 1.5 mmol), In power(173 mg, 1.5 mmol), InCl3 (22 mg, 0.1 mmol) and THF (1 mL). NH4Cl (sat.) (4 mL) was added dropwise to the suspension and stirred for 6 h. After completion of the reaction (monitored by TLC), water was added. The reaction mixture was extracted with diethyl ether, dried over anhydrous Na2SO4 and concentrated in vacuo. The crude product was purified by column chromatograph (petroleumether:ethyl acetate = 10:1) to afford the homoallylic alcohol 3a as a white solid (72% yield). In conclusion, we have found an effective system for the allylation of trichloromethyl ketones in aqueous media. The simple work of procedure, mild reaction conditions, less toxic to circumstance make our methodology a valid contribution to the existing processes in the field of allylation. Acknowledgments This work was partially supported by the National Natural Science Foundation of China (Nos. 20472062 and 20672079). The work was also supported by a research grant from the Innovation Project for graduate students of
Z.J. Bao et al. / Chinese Chemical Letters 18 (2007) 1061–1063
1063
Jiangsu Province, the Key Laboratory of Organic Synthesis of Jiangsu Province (No. JSK008), Higher Education (No. 05KJB150116). References [1] (a) K.C. Nicolaou, D.W. Kim, R. Baati, Angew. Chem. Int. Ed. 41 (2002) 3701; (b) K.R. Hornberger, C.L. Hamblet, J.L. Leighton, J. Am. Chem. Soc. 122 (2000) 12894; (c) F.X. Felpin, J. Lebreton, J. Org. Chem. 67 (2002) 9192; (d) Y. Yamamoto, Acc. Chem. Res. 20 (1987) 243. [2] (a) T. Mukaiyam, T. Harada, Chem. Lett. (1981) 1527; (b) S.H. Wu, B.Z. Huang, X. Gao, Synth. Commun. 20 (1990) 1279. [3] D. Marton, D. Stivanello, G. Tagliavini, J. Org. Chem. 61 (1996) 2731. [4] (a) F. Barbot, P. Miginiac, Tetrahedron Lett. 44 (1975) 3829; (b) C. Bernardon, A. Deberly, J. Org. Chem. 47 (1982) 463. [5] X.H. Yi, Y. Meng, X.G. Hua, C.J. Li, J. Org. Chem. 63 (1998) 7472. [6] (a) T.P. Loh, X.R. Li, Tetrahedron Lett. 5 (1997) 869; (b) K.K. Chauhan, C.G. Frost, J. Chem. Soc., Perkin Trans. 1 18 (2000) 3015; (c) C.J. Li, T.H. Chan, Tetrahedron 55 (1999) 11149; P. Cintas, Synlett 11 (1995) 1087; (d) B.C. Ranu, Eur. J. Org. Chem. (2000) 2347; (e) J. Lu, S.J. Ji, T.P. Loh, Chem. Commun. (2005) 234; (f) M.D. Preite, A. Pe´rez-Carvajal, Synlett (2006) 3337; (g) J. Auge, N. Lubin-Germain, S. Marque, L. Seghrouchni, J. Organoment. Chem. 679 (2003) 79; (h) C.M. Gordon, C. Ritchie, Green Chem. 4 (2002) 124. [7] J.W. Corbett, S.S. Ko, J.D. Rodgers, S. Jeffrey, L.T. Bacheler, R.M. Klabe, S. Diamond, C.M. Lai, S.R. Rabel, J.A. Saye, S.P. Adams, G.L. Trainor, P.S. Anderson, S.K. Erickson-Viitanen, Antimicrob. Agents Chemother. 43 (1999) 2893. [8] M.M. Christelle, J.A. David, D.B. Steven, G.D. Stephen, H.P. Hussona, Tetrahedron: Asymmetry (2001) 149. [9] J.K. Falck, A. He, R. Bejot, C. Mioskowski, Synlett 16 (2006) 2652. [10] Z. Wang, S. Campagna, K. Yang, G.Y. Xu, M.E. Pierce, J.M. Fortunak, P.N. Confalone, J. Org. Chem. 65 (2000) 1889.
Indium-mediated allylation of aryl trichloromethyl ketones in aqueous media Zhi Jian Bao, Jun Lu, Shun Jun Ji * Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry and Chemical Engineering, Suzhou (Soochow) University, Suzhou 215123, China Received 14 May 2007
Abstract It is described that indium-mediated allylation of trichloromethyl ketones could afford the corresponding homoallylic alcohols smoothly in aqueous media. # 2007 Shun Jun Ji. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. Keywords: Indium; Trichloromethyl ketone; Allylation; Aqueous media
The development of Barbier-type carbon–carbon bond formations could offer tremendous opportunities in synthetic organic chemistry. This is because homoallylic alcohols are versatile intermediates that can be converted to a wide variety of synthetically useful compounds [1]. Up to now, many metals have been used in the allylation, such as Sn [2], Zn [3], Mg [4], and Cd [5]. In recent years, the chemistry of indium has become more popular in organic synthesis. Indium has also been performed in water or aqueous solvent systems in order to minimize the use of hazardous solvents. Indium metal for Barbier-type reaction has been reported several times [6]. In spite of the application in synthesis, little is known about the allylation of ketones. Because the activity of ketones are so poor that they can hardly reacted with allyl halid, especially the activity of trihalogenmethyl ketones is poorer to be reacted. To the best of our knowledge, there was no report for the allylation of trihalogenmethyl ketones in aqueous media. Moreover, trihalogenmethyl compounds are important intermediates in organic synthesis. They can be converted to medicines for the treatment of AIDS [7], aminophenol [8], alkenes [9], alkynes [10], etc. Therefore, we hope to achieve allylation of trihalogenmethyl ketones. In this paper, we report the allylation reaction of aryl trichloromethyl ketones using In/InCl3/NH4Cl (sat.)/THF as the reaction system. It is a new, efficient synthetic method for the allylation reaction of trichloromethyl ketones (Scheme 1). In our initial studies, the In-mediated allylation reaction of trichloromethyl phenyl ketone with allyl bromide was carried out in THF, but no product was found. Therefore, saturated NH4Cl solution was introduced to enhance the reaction, the desired product could be obtained, whereas the product was obtained in low yield (30%). Some other Lewis acids were also chosen to enhance the reaction. To our delight, the product could be obtained in good yield
* Corresponding author. E-mail address: [email protected] (S.J. Ji). 1001-8417/$ – see front matter # 2007 Shun Jun Ji. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. doi:10.1016/j.cclet.2007.07.035
1062
Z.J. Bao et al. / Chinese Chemical Letters 18 (2007) 1061–1063
Scheme 1. Table 1 Optimization of the reaction conditions Entry
Systema
Time (h)
Yield (%)
1 2 3 4 5 6 7
THF InCl3 + THF ITHF + NH4Cl (sat.) THF + HCl (0.1N) In(OTf)3 + THF + NH4Cl (sat.) H2O + EtOH THF + InCl3 + NH4Cl (sat.)
24 24 24 24 24 24 6
N.R. N.R. 30 16 58 50 72
a
THF (1 mL), InCl3/In(OTf)3 (0.1 equiv.), NH4Cl(sat.)/EtOH/HCl (4 mL), H2O (1 mL).
Table 2 Allylation of aryl trichloromethyl ketones with allyl bromide Entry
Ar
Product
Time (h)
Yielda (%)
1 2 3 4 5 6 7 8
C6H5 4-ClC6H4 4-MeOC6H4 3-MeOC6H4 4-MeC6H4 1-Naphthyl 2-Naphthyl 2-Thiophene
3a 3b 3c 3d 3e 3f 3g 3h
6 20 4 4 5 6 6 20
72 78 68 58 72 40 74 63
a
Isolated yields.
(72%) when InCl3 (10 mmol%) was added to the reaction system. Lower yields were found when other reaction systems were used. The results obtained were shown in Table 1. Having optimized the reaction conditions, we extended the indium-mediated allylation to a wide variety of trichloromethyl ketones. The generality and scope of the reaction was summarized in Table 2. All products were characterized by IR, 1H NMR, and EA or MS. As was seen from Table 2, trichloromethyl ketones carrying either electron-donating or electron-withdrawing substituents could react to afford the homoallylic alcohols in moderate to good yields. The heteroaromatic ketones also could be afforded the corresponding homoallylic alcohols. General procedure. A 25 mL RBF was charged with 2,2,2-trichloro-1-phenylethanone (223 mg, 1 mmol), allyl bromide(182 mg, 1.5 mmol), In power(173 mg, 1.5 mmol), InCl3 (22 mg, 0.1 mmol) and THF (1 mL). NH4Cl (sat.) (4 mL) was added dropwise to the suspension and stirred for 6 h. After completion of the reaction (monitored by TLC), water was added. The reaction mixture was extracted with diethyl ether, dried over anhydrous Na2SO4 and concentrated in vacuo. The crude product was purified by column chromatograph (petroleumether:ethyl acetate = 10:1) to afford the homoallylic alcohol 3a as a white solid (72% yield). In conclusion, we have found an effective system for the allylation of trichloromethyl ketones in aqueous media. The simple work of procedure, mild reaction conditions, less toxic to circumstance make our methodology a valid contribution to the existing processes in the field of allylation. Acknowledgments This work was partially supported by the National Natural Science Foundation of China (Nos. 20472062 and 20672079). The work was also supported by a research grant from the Innovation Project for graduate students of
Z.J. Bao et al. / Chinese Chemical Letters 18 (2007) 1061–1063
1063
Jiangsu Province, the Key Laboratory of Organic Synthesis of Jiangsu Province (No. JSK008), Higher Education (No. 05KJB150116). References [1] (a) K.C. Nicolaou, D.W. Kim, R. Baati, Angew. Chem. Int. Ed. 41 (2002) 3701; (b) K.R. Hornberger, C.L. Hamblet, J.L. Leighton, J. Am. Chem. Soc. 122 (2000) 12894; (c) F.X. Felpin, J. Lebreton, J. Org. Chem. 67 (2002) 9192; (d) Y. Yamamoto, Acc. Chem. Res. 20 (1987) 243. [2] (a) T. Mukaiyam, T. Harada, Chem. Lett. (1981) 1527; (b) S.H. Wu, B.Z. Huang, X. Gao, Synth. Commun. 20 (1990) 1279. [3] D. Marton, D. Stivanello, G. Tagliavini, J. Org. Chem. 61 (1996) 2731. [4] (a) F. Barbot, P. Miginiac, Tetrahedron Lett. 44 (1975) 3829; (b) C. Bernardon, A. Deberly, J. Org. Chem. 47 (1982) 463. [5] X.H. Yi, Y. Meng, X.G. Hua, C.J. Li, J. Org. Chem. 63 (1998) 7472. [6] (a) T.P. Loh, X.R. Li, Tetrahedron Lett. 5 (1997) 869; (b) K.K. Chauhan, C.G. Frost, J. Chem. Soc., Perkin Trans. 1 18 (2000) 3015; (c) C.J. Li, T.H. Chan, Tetrahedron 55 (1999) 11149; P. Cintas, Synlett 11 (1995) 1087; (d) B.C. Ranu, Eur. J. Org. Chem. (2000) 2347; (e) J. Lu, S.J. Ji, T.P. Loh, Chem. Commun. (2005) 234; (f) M.D. Preite, A. Pe´rez-Carvajal, Synlett (2006) 3337; (g) J. Auge, N. Lubin-Germain, S. Marque, L. Seghrouchni, J. Organoment. Chem. 679 (2003) 79; (h) C.M. Gordon, C. Ritchie, Green Chem. 4 (2002) 124. [7] J.W. Corbett, S.S. Ko, J.D. Rodgers, S. Jeffrey, L.T. Bacheler, R.M. Klabe, S. Diamond, C.M. Lai, S.R. Rabel, J.A. Saye, S.P. Adams, G.L. Trainor, P.S. Anderson, S.K. Erickson-Viitanen, Antimicrob. Agents Chemother. 43 (1999) 2893. [8] M.M. Christelle, J.A. David, D.B. Steven, G.D. Stephen, H.P. Hussona, Tetrahedron: Asymmetry (2001) 149. [9] J.K. Falck, A. He, R. Bejot, C. Mioskowski, Synlett 16 (2006) 2652. [10] Z. Wang, S. Campagna, K. Yang, G.Y. Xu, M.E. Pierce, J.M. Fortunak, P.N. Confalone, J. Org. Chem. 65 (2000) 1889.