Piperidine → (9H-fluoren-9-yl)methyl piperidine-1-carboxylate

Participants

Reaction Steps

The resin was deprotected using a 20% solution of piperidine in DMF (1×3 min, 1×7 min, 20 ml each) and subsequently washed with DMF (1×20 ml). Acylation was carried out by addition of FmocMetOH (2.4 g, 3 eq), DMF (10 ml), HOBt (990 mg, 3 eq), and DIC (1.01 ml, 3 eq) and DMAP (260 mg, 0.1 eq). The coupling was left for 4 h and the resin was washed with DMF (7×20 ml). A small sample was dried carefully and deprotected with DCM/piperidine (1:1) for 30 min. Photometric determination of the resulting Fmoc-piperidine adduct (absorption at 301 nm) gave a resin loading of 0.43 m mol/g. The remaining resin was capped using a solution of acetic anhydride (2 M) and DMAP (0.1 M) in DMF (20 ml, 1×10 min) and subsequently washed with DMF (12×20 ml), methanol (3×40 ml) and diethyl ether (3×40 ml), and dried in vacuo to yield 3.9 g FmocMet-Rinkamide resin.

Provenance & Evidence