Ligand-Controlled Regioselective Pd-Catalyzed Diamination of Alkenes

Abstract

A ligand-controlled system has been disclosed for the regioselective palladium-catalyzed diamination of unactivated alkenes, which provides an easy access to a variety of aminofunctionalized piperidines and pyrrolidines. The steric hindrance of ligands controlled the regioselectivtities of products. 6-Endo diamination occurred with less sterically hindered quinox ligand to afford 3-aminopiperidines, while 5-exo diamination occurred with sterically bulky pyox ligand to give amino-substituted pyrrolidines.

Direct α-Alkenylation of Cyclic Amines with Maleimides through Fe(III)-Catalyzed C(sp3)–H/C(sp2)–H Cross Dehydrogenative Coupling

“…After having established an efficient synthesis of αmaleimide substituted cyclic amines with piperidines and morpholines as the substrates, we were then curious about whether this new protocol could be applied for the αfunctionalization of pyrrolidines. 9 Thus, 1-phenylpyrrolidine (4a) was treated with 2a under standard conditions as shown in Table 1, entry 15. To our delight, the desired 1-phenyl-3-(1phenylpyrrolidin-2-yl)-1H-pyrrole-2,5-dione (5a) was obtained in 75% yield (Table 3).…”

“…13 C{ 1 H} NMR (150 MHz, CDCl 3 ): δ 170. 9,170.0,150.6,149.7,136.3,129.3,128.7,128.5,128.2,127.8,120.8,118.0,53.0,49.2,41.4,30.5,25.6,21.3. HRMS (ESI) 347.1754; found, 347.1750.…”

Recent Advances in the Synthesis of Five‐membered Nitrogen Heterocycles Induced by Palladium Ions and Complexes

“…Furthermore, the usage of a sterically bulky 1‐pyridinyloxazoline Pyox chiral ligand allowed the regio‐ and enantioselective 5‐ exo aminotrifluoromethoxylation of the diphenyl‐substituted substrate (78 %, 97 : 3 ee , CsOCF 3 , THF/CH 2 Cl 2 , −25 °C, 48 h). In their other contribution, a ligand‐controlled regioselective diamination of unactivated alkenes promoted by palladium acetate in the presence of Pyox ligand L 1a and N ‐fluorobenzenesulfonimide (NFSI) was disclosed [18b] . The latter served as oxidant and an electrophilic aminating agent.…”

Catalytic, Enantioselective Diamination of Alkenes

“…Scheme 11 Enantioselective diamination of terminal alkenes with 1azido-1,2-benziodoxol-3(1H)-one Shortly thereafter, the same group reported the cyclization of related sulfonamide tethered terminal alkenes by Pd-catalyzed diamination reactions with NFSI as the nitrogen source and oxidant (Scheme 12). 32 It is noteworthy that the regioselectivity of this process can be modulated through modulation of the ligand architecture. With ligand L7, 6-endo-cyclization is favored, whereas with ligand L8, 5exo-cyclization is favored.…”