Macromolecular Research, Vol.16, No.5, 441-445, July, 2008
Ring-Opening Polymerization of ε-Caprolactone and Cyclohexene Oxide Initiated by Aluminum β-Ketoamino Complexes: Steric and Electronic Effect of 3-Position Substituents of the Ligands
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A series of aluminum complexes supported by β-ketoamino, ligand-bearing, 3-position substituents LAlEt2 (L=CH3C(O)C(Cl)=C(CH3)NAr (L1), L=CH3C(O)C(H)=C(CH3)NAr (L2), L=CH3C(O)C(Ph)=C(CH3)NAr(L3), and L=CH3C(O)C(Me)=C(CH3)NAr (L4), Ar=2,6-iPr2C6H3) were synthesized in situ and employed in the ringopening polymerization (ROP) of ε-caprolactone (ε-CL) and cyclohexene oxide (CHO). The 3-position substituents on the β-ketoamino ligand backbone of the aluminum complexes influenced the catalyst activity remarkably for both ROP of ε-CL and CHO. Aluminum β-ketoamino complexes displayed different catalytic behavior in ROP of ε-CL and CHO. The order of the catalytic activity of LAlEt2 was L1AlEt2>L2AlEt2>L3AlEt2>L4AlEt2 for ROP of ε-CL, being opposite to the electron-donating ability of the 3-position substituents on the β-ketoamino ligand, while the order of the catalytic activity for ROP of CHO was L1AlEt2>L3AlEt2>L4AlEt2>L2AlEt2. The effects of reaction temperature and time on the ROP were also investigated for both ε-CL and CHO.
Keywords:ring-opening polymerization;ε-caprolactone;cyclohexene oxide;aluminum β-ketoamino complexes
- Ohtsuka Y, Ikeno T, Yamada T, Tetrahedron: Asymmetry, 11, 3671 (2000)
- Mita T, Ikeno T, Yamada T, Org. Lett., 4, 2457 (2002)
- Jones D, Roberts A, Cavell K, Keim W, Englert U, Skelton BW, White AH, J. Dalton. Trans., 255 (1998)
- Zh YZ, Liu JY, Li YS, Tong YJ, J. Organomet. Chem., 689, 1295 (2004)
- He XH, Yao YZ, Luo X, Zhang JK, Liu YH, Zhang L, Wu Q, Organometallics, 22, 4952 (2003)
- Tang LM, Duan YQ, Pan L, Li YS, J. Polym. Sci. A: Polym. Chem., 43, 1681 (2005)
- Wang HY, Zhang J, Meng X, Jin GX, J. Organomet. Chem., 691, 1275 (2006)
- Zhang D, Jin GX, Weng LH, Wang FS, Organometallics, 23, 327 (2004)
- Bao F, Lue XQ, Kang BS, Wu Q, Eur. Polym. J., 42, 928 (2006)
- Liu BY, Tian CY, Zhang L, Yan WD, Zhang WJ, J. Polym. Sci. A: Polym. Chem., 44, 6243 (2006)
- Yu RC, Hung CH, Huang JH, Lee HY, Chen JT, Inorg. Chem., 41(24), 6450 (2002)
- Shuka P, Gordon JC, Cowley AH, Jones JN, J. Org. Chem., 690, 1366 (2005)
- Kuo PC, Chen IC, Lee HM, Hung CH, Huang JH, Inorg. Chim. Acta., 358, 3761 (2005)
- Doherty S, Errington RJ, Housley N, Clegg W, Organometallics, 23, 2382 (2004)
- Yamamoto HE, Lewis Acids in Organic Synthesis, Wiley-VCH, New York (2000)
- Atwood DA, Harvey MJ, Chem. Rev., 101(1), 37 (2001)
- Aida T, Inoue S, Accounts Chem. Res., 29, 39 (1996)
- Liu YC, Ko BT, Lin CC, Macromolecules, 34(18), 6196 (2001)
- Chen CT, Huang CA, Huang BH, Dalton. Trans., 3799 (2003)
- Pang X, Du HZ, Chen XS, Zhuang XL, Cui DM, Jing XB, J. Polym. Sci. A: Polym. Chem., 43(24), 6605 (2005)
- Timol SM, Luximon AB, Jhurry D, Macromol. Symp., 231, 69 (2006)
- Hormnirun P, Marshall EL, Gibson VC, White AJP, Williams DJ, J. Am. Chem. Soc., 126(9), 2688 (2004)
- Moore DR, Cheng M, Lobkovsky EB, Coates GW, Angew. Chem. Int. Ed., 41, 2599 (2002)
- Nomura N, Aoyama T, Ishii R, Kondo T, Macromolecules, 38(13), 5363 (2005)
- Alcazar-Roman LM, O'Keefe BJ, Hillmyer MA, William BT, Dalton. Trans., 3082 (2003)
- Byun SH, Seo HS, Lee SH, Ha CS, Kim I, Macromol. Res., 15(5), 393 (2007)
- Tian J, Feng YK, Xu YS, Macromol. Res., 14(2), 209 (2006)
- Clegg W, Cope EK, Edwards AJ, Mair FS, Inorg. Chem., 37(9), 2317 (1998)
- Mcdaniel DH, Brown HC, J. Org. Chem., 23, 420 (1958)