[en] A range of new imidazolium and imidazolinium chlorides bearing biphenyl units on their nitrogen atoms was synthesized. They differed by the electron-withdrawing or -donating nature and the steric bulk of the substituents on their aromatic rings. These various N-heterocyclic carbene (NHC) precursors were combined with the [RuCl2(p-cymene)](2) dimer and potassium tert-butoxide to generate the corresponding ruthenium-arene complexes [RuCl2(p-cymene)(NHC)] in situ. The catalytic activity of these species was investigated in the photoinduced ring-opening metathesis polymerization (ROMP) of cyclooctene. The results obtained confirmed the necessity of blocking the ortho-positions of the phenyl rings in the vicinity of the metal center in order to attain high catalytic efficiencies. They also showed that changing the steric and electronic properties of the substituents on the remote phenyl rings of the biphenyl units had no significant influence on the outcome of the polymerization. (C) 2007 Elsevier B.V. All rights reserved.
Disciplines :
Chemistry
Author, co-author :
Maj, Anna M.
Delaude, Lionel ; Université de Liège - ULiège > Chimie macromoléculaire et catalyse organique
Demonceau, Albert ; Université de Liège - ULiège > Chimie macromoléculaire et catalyse organique
Noels, Alfred ; Université de Liège - ULiège > Services généraux (Faculté des sciences) > Relations académiques et scientifiques (Sciences)
Language :
English
Title :
Synthesis of N-heterocyclic carbene precursors bearing biphenyl units and their use in ruthenium-catalyzed ring-opening metathesis polymerization
Frenzel U., and Nuyken O. J. Polym. Sci. A: Polym. Chem. 40 (2002) 2895
Slugovc C. Macromol. Rapid Commun. 25 (2004) 1283
Connon S.J., and Blechert S. Angew. Chem., Int. Ed. 42 (2003) 1900
Delaude L., Demonceau A., and Noels A.F. Curr. Org. Chem. 10 (2006) 203
Delaude L., Demonceau A., and Noels A.F. Chem. Commun. (2001) 986
Delaude L., Szypa M., Demonceau A., and Noels A.F. Adv. Synth. Catal. 344 (2002) 749
Stanforth S. Tetrahedron 54 (1998) 263
Lloyd-Williams P., and Giralt E. Chem. Soc. Rev. 30 (2001) 145
Arduengo III A.J., Krafczyk R., Schmutzler R., Craig H.A., Goerlich J.R., Marshall W.J., and Unverzagt M. Tetrahedron 55 (1999) 14523
Huang J., and Nolan S.P. J. Am. Chem. Soc. 121 (1999) 9889
Maj A.M., Delaude L., Demonceau A., and Noels A.F. Tetrahedron 63 (2007) 2657
Trnka T.M., Morgan J.P., Sanford M.S., Wilhelm T.E., Scholl M., Choi T.-L., Ding S., Day M.W., and Grubbs R.H. J. Am. Chem. Soc. 125 (2003) 2546
In a recent work on microwave-assisted synthesis of imidazolinium salts (A. Aidouni, A. Demonceau, L. Delaude, Synlett (2006) 493), we have shown that the presence of formic acid was not required to achieve high yields of cyclized products. The present study was, however, carried out under conventional heating conditions and we did not check that formic acid was indeed required, although we suspect that its presence might not be essential to the success of the reaction.
Lebedev B., Smirnova N., Kiparisova Y., and Makovetsky K. Makromol. Chem. 193 (1992) 1399
Lebedev B., and Smirnova N. Macromol. Chem. Phys. 195 (1994) 35
Scholl M., Ding S., Lee C.W., and Grubbs R.H. Org. Lett. 1 (1999) 953
Liu Y., and Lemal D.M. Tetrahedron Lett. 41 (2000) 599
Alder R.W., Blake M.E., Chaker L., Harvey J.N., Paolini F., and Schütz J. Angew. Chem., Int. Ed. 43 (2004) 5896
Gök Y., Çetinkaya E., Özdemir I., Çetinkaya B., and Lappert M.F. Acta Chim. Slov. 51 (2004) 437
Wanzlick H.-W., Lachmann B., and Schikova E. Chem. Ber. 98 (1965) 3170
Hocker J., and Merten R. Chem. Ber. 105 (1972) 1651
Arduengo III A.J., Calabrese J.C., Davidson F., Rasika Dias H.V., Goerlich J.R., Krafczyk R., Marshall W.J., Tamm M., and Schmutzler R. Helv. Chim. Acta 82 (1999) 2348
Csihony S., Culkin D.A., Sentman A.C., Dove A.P., Waymouth R.M., and Hedrick J.L. J. Am. Chem. Soc. 127 (2005) 9079
Hillier A.C., Sommer W.J., Yong B.S., Petersen J.L., Cavallo L., and Nolan S.P. Organometallics 22 (2003) 4322
Dorta R., Stevens E.D., Scott N.M., Costabile C., Cavallo L., Hoff C.D., and Nolan S.P. J. Am. Chem. Soc. 127 (2005) 2485
Arduengo III A.J., Gamper S.F., Tamm M., Calabrese J.C., Davidson F., and Craig H.A. J. Am. Chem. Soc. 117 (1995) 572
Arduengo III A.J., Rasika Dias H.V., Harlow R.L., and Kline M. J. Am. Chem. Soc. 114 (1992) 5530
Smith M.B., and March J. March's Advanced Organic Chemistry (2001), Wiley-Interscience, New York pp. 368-380
Süßner M., and Plenio H. Chem. Commun. (2005) 5417
Pretsch E., Bühlmann P., and Affolter C. Structure Determination of Organic Compounds. 3rd ed. (2003), Springer, Berlin