[CH3:1][Si:2]([CH3:7])([CH3:6])[CH2:3][CH2:4][OH:5].[C:8]([CH2:10][C:11](O)=[O:12])#[N:9].C1(N=C=NC2CCCCC2)CCCCC1.N1(C2C=CN=CC=2)CCCC1>C(OCC)C>[CH3:1][Si:2]([CH3:7])([CH3:6])[CH2:3][CH2:4][O:5][C:11](=[O:12])[CH2:10][C:8]#[N:9]2000 mg (16.91 mmol) 2-(Trimethylsilyl)ethanol are dissolved in 160 ml diethylether. 1307 mg (15.38 mmol) cyanoacetic acid, 3489 mg (16.91 mmol) N,N′-dicyclohexylcarbodiimide and 227 mg (1.54 mmol) 4-(1-pyrrolidinyl)pyridine are added. The mixture is stirred at room temperature for 3 hours under an argon atmosphere and kept at room temperature overnight. The suspension is filtered and the filtrate is washed twice with 5% aqueous acetic acid and twice with water. The organic phase is dried over sodium sulfate, filtered and the solvent is evaporated in vacuo. The residue is re-dissolved in 10 ml hexane and the suspension is filtered over 1 g silica. After evaporation of the solvent, distillation at 0.51 mbar yields the desired product.
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