Dicyclohexylamine → HCID 12944586, compound

Participants

Reaction Conditions

Reaction Steps

To 100 ml. of THF were added 10.6 grams (15 mmoles) of Nα -t-butyloxycarbonyl-L-phenylalanine. The mixture was added dropwise over a one hour period to a mechanically stirred suspension of 0.12 moles of potassium hydride in 250 ml. of dried THF containing 0.5 grams of 18-crown-6-ether at 0° C. and under a nitrogen atmosphere. The mixture was stirred for an additional 10 minutes at 0° C., and a solution of 4 ml. (44 mmoles) of allyl iodide in 20 ml. of THF was added dropwise over a 30 minute period. The resulting mixture was maintained for four hours after which a mixture of 4.6 ml. of glacial acetic acid in 20 ml. of THF was added dropwise. The mixture was stirred for 10 minutes and then was poured onto 400 ml. of ice. The aqueous phase was adjusted to pH 8.0 by addition of 1 N sodium hydroxide. The aqueous phase then was extracted with ether and acidified to pH 2.0 with cold 1 N HCl. The aqueous mixture then was extracted with ethyl acetate. The ethyl acetate was extracted with water, dried over magnesium sulfate, and evaporated in vacuo to a syrup. The syrup was dissolved in 200 ml. of ether, and 8 ml. (0.04 moles) of dicyclohexylamine (DCHA) were added. The resulting precipitate was filtered, and the filtrate was extracted successively with 1.5 N citric acid and water. The ether layer was dried over magnesium sulfate and evaporated in vacuo to obtain 9 grams (74%) of the title compound as a syrup.

Provenance & Evidence