Unexpected side reactions of imidazolium-based ionic liquids in the base-catalysed Baylis-Hillman reaction.

Low yields are obtained when the Baylis-Hillman reaction is conducted in the presence of an imidazolium-based ionic liquid due to direct addition of the deprotonated imidazolium salt to the aldehyde. Ionic liquids are evidently not inert.

[1]  W. Marshall,et al.  A stable diaminocarbene , 1995 .

[2]  C. Afonso,et al.  Ionic liquids as a recyclable reaction medium for the Baylis–Hillman reaction , 2001 .

[3]  D. Enders,et al.  The Chemistry of Stable Carbenes. Part 2. Benzoin‐type condensations of formaldehyde catalyzed by stable carbenes , 1996 .

[4]  A. Miyashita,et al.  Catalytic Action of Azolium Salts. III. Aroylation of N-Phenylbenzimidoyl Chlorides with Aromatic Aldehydes in the Presence of 1, 3-Dimethylimidazolium Iodide , 1992 .

[5]  J. Hine,et al.  Basicity of, SN2 reactivity of, and basic catalysis by 1-azabicyclo[2.2.1]heptane , 1987 .

[6]  K. R. Seddon.  Room‐Temperature Ionic Liquids: Neoteric Solvents for Clean Catalysis , 1997 .

[7]  P. Wasserscheid,et al.  Ionic Liquids-New "Solutions" for Transition Metal Catalysis. , 2000, Angewandte Chemie.

[8]  W. Herrmann,et al.  Heck reaction catalyzed by phospha-palladacycles in non-aqueous ionic liquids , 1999 .

[9]  V. Aggarwal,et al.  Rate acceleration of the Baylis-Hillman reaction in polar solvents (water and formamide). Dominant role of hydrogen bonding, not hydrophobic effects, is implicated. , 2002, The Journal of organic chemistry.

[10]  T. Kitazume,et al.  Preparation of fluorinated alkenes in ionic liquids , 2000 .

[11]  V. Aggarwal,et al.  Metal- and Ligand-Accelerated Catalysis of the Baylis-Hillman Reaction. , 1998, The Journal of organic chemistry.

[12]  Ronald Breslow,et al.  On the Mechanism of Thiamine Action. IV.1 Evidence from Studies on Model Systems , 1958 .