[Li+].C[CH:3]([N-:5]C(C)C)C.[CH2:9]1[C:13]2([CH2:18][CH2:17][C:16](=[O:19])[CH2:15][CH2:14]2)[CH2:12][CH2:11][CH2:10]1.S(C#N)(C1C=CC(C)=CC=1)(=O)=O>C1COCC1>[O:19]=[C:16]1[CH2:17][CH2:18][C:13]2([CH2:9][CH2:10][CH2:11][CH2:12]2)[CH2:14][CH:15]1[C:3]#[N:5]LDA (1.83 mL, 3.66 mmol, 2.0 M in hexanes) was combined with THF (3.2 mL) and cooled to −78° C. To this mixture was added a solution of spiro[4.5]decan-8-one (0.50 g, 3.3 mmol) in THF (3.2 mL). The resulting mixture was stirred at −78° C. for 20 mins then taken up in a syringe and added to a mixture of tosyl cyanide (0.59 g, 3.3 mmol) in THF (3.2 mL) at −78° C. The reaction mixture was allowed to stir at −78° C. for 45 mins then quenched with 0.5M NaOH and extracted with EtOAc (2×). The combined organic extracts were washed with 1N aqueous HCl, brine, dried over anhydrous Na2SO4, filtered, and concentrated in vacuo. The crude residue was purified by MPLC on silica gel (using a gradient elution of 0-50% EtOAc/hexanes). Desired fractions were identified, combined and concentrated in vacuo to afford the title compound. The residue was carried forward without further purification.
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