Lithium Hexamethyldisilazide → HCID 86701199, compound

Participants

Reaction Conditions

Reaction Steps

Lithium bis(trimethylsilyl)amide (1.0 mol/L in tetrahydrofuran; 8.0 mL) is added dropwise to 5-bromo-2-chloro-4-picoline (0.81 g) dissolved in tetrahydrofuran (10 mL) at −45° C. under Ar atmosphere. The solution is stirred at −35 to −45° C. for 0.5 h prior to dropwise addition of 2-oxo-7-aza-spiro[3.5]nonane-7-carboxylic acid tert-butyl ester (1.00 g) dissolved in tetrahydrofuran (5 mL). The reaction mixture is stirred at −40° C. for 45 min before the cooling bath is removed. At room temperature the reaction is quenched with aqueous NH4Cl solution and the resulting mixture is extracted with ethyl acetate. The combined extracts are dried (Na2SO4) and concentrated. The residue is chromatographed on silica gel (cyclohexane/ethyl acetate 4:1→1:1) to give the title compound. LC (method 1): tR=1.36 min; Mass spectrum (ESI+): m/z=445 [M+H]+.

Provenance & Evidence