L-Lysine → Ninhydrin

Participants

Reaction Steps

To the deprotected Lys-resin sample was added Fmoc-Phe (8.8 mg, 33.2 μmol) in DCM/DMF and 1,3-diisopropylcarbodiimide (DIC) (3 μL, 20 μmol). The coupling reaction was continued for 2 h and ninhydrin tests gave negative amino group readings. The Fmoc-Phe-Lys(ivDde) on resin was then treated with photogenerated piperidine as described above. Upon completion of the reaction, the resin was washed with DCM/DMF. Capping of the NH2-Phe-Lys(ivDde)-resin was carried out for 1 h with acetic anhydride (470 μL, 5 mmol) and TEA (700 μL, 5 mmol) in 1.5 mL DMW to give Ac-Phe-Lys(ivDde)-resin.

Provenance & Evidence