Dicyclohexylcarbodiimide → HCID 69516255, compound

Participants

Reaction Steps

To (4S)-3-(tert-butoxycarbonyl)-1,3-oxazolidine-4-carboxylic acid (11.15 g, 0.051 mol), Meldrum's acid (7.33 g, 0.051 mol), dimethylaminopyridine (12.44 g, 0.102 mol) and DCM (200 ml) was added 1,3-dicyclohexylcarbodiimide (10.52 g, 0.051 mol). After 24 h the reaction was filtered, extracted twice with 1N HCl (200 ml) once with water, dried (Na2SO4), filtered, concentrated, then warmed to reflux in 100% ethanol for 2 h. The reaction was concentrated to a pale yellow oil (14.3 g). A portion of this material (5.88 g, 0.02 mol) was refluxed 2 h using Dean Stark trap with 4-carboxybenzaldehyde (3.0 g, 0.02 mol), piperidine (110 mg, 0.0012 mol) and toluene (100 ml). The reaction was filtered, concentrated to give A as a yellow gum (7.1 g, 85%). LCMS m/z 420 (MH+).

Provenance & Evidence