[Zn:1].[Li+].[Cl-].I[CH2:5][CH2:6][C:7]#[N:8].[C:9]([O-:15])(=[O:14])[C:10]([CH3:13])([CH3:12])[CH3:11].[Li+]>C1COCC1>[C:9]([O-:15])(=[O:14])[C:10]([CH3:13])([CH3:12])[CH3:11].[C:7]([CH2:6][CH2:5][Zn+:1])#[N:8]Zinc powder (490 mg, 7.5 mmol) and LiCl (318 mg, 7.5 mmol) were placed in a Schlenk-flask, equipped with a magnetic stirrer and a septum, dried for 5 min at 400° C. (heat gun) in high vacuum and then dissolved in 7.0 mL of dry THF. 4 drops of 1,2-dibromoethane were added and the mixture was heated to boiling for the activation of the zinc dust. After cooling to 22° C. 3-iodopropionitrile (905 mg, 5.0 mmol) was added dropwise and the mixture was stirred for 2 h at 22° C. The stirring of the reaction mixture was stopped and the excess zinc dust was sedimented. The supernatant solution was transferred to another Schlenk-flask containing a solution of lithium pivalate (811 mg, 1.50 mmol) prepared as described above in 5.0 mL of dry THF. The mixture was stirred for 15 min at 22° C. and then the solvent was removed in vacuo. (2-cyanoethyl)zinc pivalate was obtained as a yellow solid (2.94 g). The content of active zinc species was determined by titration of 398 mg of the reagent with a stock solution of iodine (1.0 M in THF). A concentration of 1020 mg/mmol was determined which corresponds to a yield of 58%.
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