Synthese de β-fluoroamines

Highly Diastereoselective and General Synthesis of Primary β-Fluoroamines

“…Hydrogenation and standard acid-mediated deprotection provide chiral cyclic primary β-fluoroamine 18 in 70% overall yield for the four-step sequence, a notable improvement over the classical route. The relative stereochemistry of 18 was confirmed by correlation with previously reported 19 F NMR shifts for cis - (−197 ppm) and trans -cyclic β-fluoroamines (−180 ppm), wherein 18 displayed a singlet at −198 ppm …”

“…The relative stereochemistry of 18 was confirmed by correlation with previously reported 19 F NMR shifts for cis - (−197 ppm) and trans -cyclic β-fluoroamines (−180 ppm), wherein 18 dsiplayed a singlet at −198 ppm. 29 …”

A General Nickel-Catalyzed Hydroamination of 1,3-Dienes by Alkylamines: Catalyst Selection, Scope, and Mechanism

“…13 (2-Cyclohexen-1-yl)cyclohexylamine (Entry 7). 46 Product from reaction for 37 h on a 2 mmol scale using the general procedure was isolated by Ku ¨gelrohr distillation (50 mT, 140 °C) to give 292 mg (82% yield) of clear oil. 1 H NMR (CDCl3) δ 5.78-5.65 (m, 2H), 3.22 (m, 1H), 2.55 (m, 1H), 1.93 (m, 2H), 1.80 (m, 3H), 1.67 (m, 3H), 1.45-1.60 (m, 2H), 1.32 (m, 1H), 1.30-1.00 (m, 5H), 0.81 (br m, 1H).…”

Highly Efficient Diastereoselective Reduction of α-Fluoroimines

“…With an efficient method for the preparation of the imines in hand, we began to investigate the reaction parameters (solvent and temperature) for the diastereoselective reduction of the imine derived from α-fluorocyclohexanone and p -anisidine utilizing Cl 3 SiH. These studies showed that THF and EtOAc provided the best diastereoselectivity (17:1 syn : anti ) in the reduction of the model imine at 0 °C (Table , entries 3 and 7) . EtOAc was chosen as the optimal solvent due to its advantageous properties to industrial scale synthesis in comparison to THF, as well as the modest increase in product yield (57% to 73%).…”