Sodium hydride → 2-Cyano-2-(1-isopropyl-butyl)succinic acid 4-tert-butyl ester 1-methyl ester

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Reaction Steps

A solution of 2-cyano-3-isopropyl-hexanoic acid methyl ester (1.9 g, 9.6 mmol) in 10 mL of THF is added to a slurry of NaH (washed with hexane, 0.23 g, 9.6 mmol) in 20 mL of THF which is cooled in an ice water bath under argon. The solution is stirred for 10 minutes, and t-butyl bromoacetate (2.1 g, 10.6 mmol) is added. The solution is warmed to room temperature. After 12 hours, the reaction is quenched by addition of 50 mL of saturated KH2PO4 and the THF is evaporated. The organic products are extracted into Et2O (3×50 mL), and the combined organic layers are dried over MgSO4. The solvent is evaporated, and the remaining oil is chromographed under medium pressure over silica gel in 25% hexane/CH2Cl2. Yield of 2-cyano-2-(1-isopropyl-butyl)-succinic acid 4-tert-butyl ester 1-methyl ester=1.3 g (42%) as an oil.

Provenance & Evidence