tert-Butyl piperazine-1-carboxylate → Tert-butyl 4-(4-(2,2,2-trifluoro-1-hydroxy-1-methylethyl)phenyl)-1-piperazinecarboxylate

Participants

Reaction Conditions

Reaction Steps

A 350 mL pressure tube was charged with 2-(4-bromophenyl)-1,1,1-trifluoro-2-propanol (7.22 g, 26.8 mmol, Example 27, step 1), N-Boc-piperazine (5.00 g, 26.8 mmol), sodium tert-butoxide (3.87 g, 40.3 mmol), 50 mL of toluene, dicyclohexyl(2′,6′-diisopropoxybiphenyl-2-yl)phosphine (RuPhos) (1.253 g, 2.68 mmol, Strem Chemical Inc, Newburyport, Mass.) and tris(dibenzylideneacetone)dipalladium (0) (1.229 g, 1.342 mmol, Strem Chemical Inc, Newburyport, Mass.). The tube was sealed and heated at 100° C. for 2 h. After that time, the mixture was diluted with water (50 mL) and extracted with EtOAc (2×100 mL) to give a dark oil. Purification via column chromatography (120 g of silica gel, 0 to 40% EtOAc in hexanes) gave tert-butyl 4-(4-(2,2,2-trifluoro-1-hydroxy-1-methylethyl)phenyl)-1-piperazinecarboxylate (8.61 g) as an off-white brittle foam.

Provenance & Evidence