[C:1]([OH:6])(=[O:5])[C:2]([CH3:4])=[CH2:3].Br[CH2:8][C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10].C1CCN2C(=NCCC2)CC1.N#N>C1(C)C=CC=CC=1>[C:12]([O:11][C:9](=[O:10])[CH2:8][O:5][C:1](=[O:6])[C:2]([CH3:4])=[CH2:3])([CH3:15])([CH3:14])[CH3:13]Methacrylic acid (8.06 g, 0.10 mole), t-butyl bromoacetate (19.50 g, 0.10 mole) and 1,8-diazabicyclo[5.4.0]undoc-7-ene, DBU, (15.20 g, 0.10 mole) and 150 ml toluene were combined in a 500 ml 3-neck flask equipped with condenser, nitrogen inlet, thermometer and magnetic stirrer bar. The reaction mixture was stirred at room temperature for one hour. The reaction was continued at 90° C. overnight under a blanket of N2 flow. The mixture was cooled to room temperature and the salt was removed by filtration. The toluene solution was washed with 75 ml saturated NaCl solution and 2×75 ml Dl-water respectively before dried on MgSO4 overnight. The solid was filtered out and the toluene was removed at rotavap. An oily residue was distilled to a final clear liquid at reduced pressure.
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