A highly efficient preparation of methacrylate esters using novel solid phase titanium-based transesterification catalysts

Synlett

Volumn , Issue SPEC. ISS., 1999, Pages 957-959

  Lewis, Norman ^a   Ribas, Christina ^a   Wells, Andrew ^a  

^a GLAXOSMITHKLINE   (United Kingdom)

Author keywords

Methacrylate esters; Polymer bound titanium catalysts; Transesterification

Indexed keywords

LIGAND; POLYMETHACRYLIC ACID DERIVATIVE; TITANIUM DERIVATIVE;

ARTICLE; CATALYSIS; CATALYST; CHEMICAL MODIFICATION; ESTERIFICATION; MOLECULAR MODEL; REACTION ANALYSIS; SOLID PHASE EXTRACTION; SYNTHESIS;

EID: 0033053282     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1999-3090     Document Type: Article

References (13)

1. Seebach, D.; Hungerbuehler, E.; Naef, R.; Schnurrenberger, P.; Weidmann, B.; Zueger, M. Synthesis, 1982, 138.
2. Akelah, A. Synthesis, 1981, 413. Akelah, A.; Sherrington, D. C. Chem. Rev. 1981, 81, 557. Manecke, G.; Storck, W. Angew. Chem. Int. Ed. Engl. 1978, 17, 657.
3. Akelah, A. Synthesis, 1981, 413. Akelah, A.; Sherrington, D. C. Chem. Rev. 1981, 81, 557. Manecke, G.; Storck, W. Angew. Chem. Int. Ed. Engl. 1978, 17, 657.
4. Akelah, A. Synthesis, 1981, 413. Akelah, A.; Sherrington, D. C. Chem. Rev. 1981, 81, 557. Manecke, G.; Storck, W. Angew. Chem. Int. Ed. Engl. 1978, 17, 657.
5. Deleuze, H.; Schultze, X.; Sherrington, D.C. Polymer, 1998, 39, 6109.
6. -1 ligand was treated with chlorotriisopropoxytitanium (1.0 g, 0.004 mol) and toluene (100ml) and heated at reflux under nitrogen for 18h. The mixture was cooled and the resulting polymer beads filtered and washed with toluene. The polymer beads were then repeatedly slurried with dichloromethane and filtered until the filtrate showed no colour change when treated with a 1 % solution of hydroquinone in acetone. The resultant polymer beads were dried in vacuo at 75°C to give 9.6 g of catalyst C as white beads.
7. 6 The monomers were suspended in a mixture of water (300ml) and polyvinylalcohol (0.2 g). Dibenzoyl peroxide (1.0 g, 0.004 mol) was added and the mixture heated at reflux for 2h. The mixture was cooled, filtered and the product washed with methanol (2x150 ml), filtered, washed with acetone and dried to give 23 g of white beads. 10g of the resulting polymer was treated with chlorotriisopropoxytitanium (30ml, 0.13 mol), Hünigs base (6.5 g, 0.05 mol) and 1,2-dichloroethane (100ml) and heated at reflux under nitrogen for 19h. The mixture was cooled and the bright orange beads filtered. The polymer beads were then repeatedly slurried with dichloromethane and filtered until the filtrate showed no colour change when treated with a solution of 1% hydroquinone in acetone. The resultant polymer beads were dried in vacuo at 65°C to give 11 g of polymer D.
8. Linden, G.L.; Farona, M.F. J. Catal. 1977, 48, 284.
9. Benson, G.M.; Hickey, D.M.B.H. Patent WO 9118027, 1991; Chem. Abstr. 1992, 116, 158913. Benson, G.M.; Alston, D.R.; Bond, A.N; Gee, A.; Haynes, C.; Hickey, D.M.B.; Iqubal, S.; Jackson, B.; Jaxa-Chamiec, A.A.; Johnson, M.R.; Roberts, M.G.; Slingsby, B.P.; Whittaker, C.M.; Suckling, K.E. Atherosclerosis, 1993, 101, 51.
10. Benson, G.M.; Hickey, D.M.B.H. Patent WO 9118027, 1991; Chem. Abstr. 1992, 116, 158913. Benson, G.M.; Alston, D.R.; Bond, A.N; Gee, A.; Haynes, C.; Hickey, D.M.B.; Iqubal, S.; Jackson, B.; Jaxa-Chamiec, A.A.; Johnson, M.R.; Roberts, M.G.; Slingsby, B.P.; Whittaker, C.M.; Suckling, K.E. Atherosclerosis, 1993, 101, 51.
11. Lewis, N.J.; Wells, A.S. Patent WO 9109005,1991; Chem. Abstr. 1991, 115, 184134.
12. Wells, A.S. Synth. Commun. 1996, 26, 1143.
13. 8 (20 mL) and the polymeric catalyst C or D (5 g) was added. The mixture was heated at reflux with a slow air bleed via capilliary into the reaction whilst the methanol/methyl acrylate azeotrope was continuously removed via a Vigreux distillation column. Methyl methacrylate was added as required to maintain a constant volume. After 4h assay by gas chromatography indicated 98% conversion. The reaction mixture was cooled and the catalyst removed by filtration. The catalyst was washed with methyl methacrylate and washings were added to the reaction filtrate. The 11-bromoundecyl methacrylate 2 was isolated by distillation of excess methyl methacrylate as an oil in 87% isolated yield.