Fig. 2: Catalyst screening.
From: Asymmetric α-C(sp3)−H allylic alkylation of primary alkylamines by synergistic Ir/ketone catalysis
Reactions were carried out with 1a (0.45 mmol), 2a (0.30 mmol), carbonyl catalyst (0.030 mmol), Ir(COD)2BF4 (0.012 mmol), phosphoramidite ligand (0.0132 mmol), ZnBr2 (0.45 mmol), and DBU (0.33 mmol) in THF/H2O (1.45 mL/0.05 mL) at room temperature for 36 h. During the screening of carbonyl catalysts, phosphoramidite (R,R,Ra)-L1 was used. For the screening of phosphoramide ligands, compound 4 (DFO) was used as the carbonyl catalyst. Isolated yields based on 2a. The ee values were determined by high-performance liquid chromatography (HPLC). aThe NMR yields of 3a and 3a’ were determined by 1H NMR analysis of crude reaction mixtures. Ph phenyl, COD 1,5-cyclooctadiene, NMR nuclear magnetic resonance.
