Research Article
New L-Serine Derivative Ligands as Cocatalysts for Diels-Alder Reaction
Scheme 2
L-serine derivative ligands used in the Diels-Alder reaction between 1 and 2. Reagents and conditions: (i) Boc2O, CH2Cl2, r.t., 2 h, 86%; (ii) benzylamine, DIPEA, TBTU, CH2Cl2, r.t., 2 h, 99%; (iii) (S)-1-phenylethylamine, DIPEA, TBTU, CH2Cl2, r.t., 2 h, 100%; (iv) (R)-1-phenylethylamine, DIPEA, TBTU, CH2Cl2, r.t., 2 h, 100%.
