Ethanolamine → (S)-1,4-dibenzyl-2-(2-(3-fluoro-phenyl)-ethyl)-piperazine

Participants

Reaction Conditions

Reaction Steps

Combine (S)-1,4-dibenzyl-2-vinyl-piperazine (2.0 g, 6.84 mmol) and 9-borabicyclo[3.3.1]nonane (82.1 mL, 41.04 mmol, 0.5 M in THF) and stir at ambient temperature. After 24 hours, add 1-fluoro-3-iodo-benzene (2.3 g, 10.26 mmol), triphenylphosphine (287.0 mg, 1.09 mmol), tetrakis(triphenylphosphine) palladium(0)(158.0 mg, 0.14 mmol), and 3N NaOH (5.6 mL) and stir at 60° C. After 22 hours, add ethanolamine (10.0 mL) and dilute the mixture with water. Extract with ethyl acetate and combine, wash (brine), dry (sodium sulfate), and reduce the extracts to residue. Purify the residue on silica gel using ethyl acetate/hexanes (5:95) to give a yellow oil. Dissolve the yellow oil in acetic acid/methanol (1:9) and apply to an SCX column. Wash the column with methanol followed by 2N ammonia in methanol to give the title compound: mp 69–71° C.; mass spectrum (ion spray): m/z=389.4 (M+1).

Provenance & Evidence