Enantioselective epoxidation of nonfunctionalized alkenes catalyzed by recyclable new homochiral bis-diamine-bridged bi-Mn(salen) complexes

Efficient and convenient epoxidation of alkenes to epoxides with H2O2 catalyzed by Co(OAc)2 in ionic liquid [C12py][PF6]

“…Besides Co(OAc) 2 , we also tried to use other types of catalysts in this model reaction (Table 1, entries [12][13][14][15][16], and the results showed that Co(OAc) 2 demonstrated the best performance in terms of yield and reaction rate. Therefore, the combination of H 2 O 2 , Co(OAc) 2 and [C 12 py][PF 6 ] was chosen as the optimal conditions for further exploration.…”

“…For a typical experiment, alkene (10 mmol), Co(OAc) 2 (1 mmol), and an aqueous solution of H 2 O 2 (30 %, 11 mmol) were sequentially added to 10 mL of [C 12 py] [PF 6 ]. The obtained mixture was stirred vigorously at room temperature for the appropriate time (Table 2), the reaction progress was monitored by GC.…”

“…[3][4][5], and suffer from considerable drawbacks such as low yield, harsh or delicate reaction condition, and a large amount of waste byproducts. Oxidation with NaClO [6,7], PAA [8], TBHP [9,10], PhIO [11,12], NaIO 4 [13,14], CHP [15], oxone [16][17][18], peracetic acid [19,20], TADOOH [21], PPO [22], and other reagents [23][24][25][26][27][28] have also been developed for this conversion. However, these protocols are generally associated with one or more disadvantages, such as complex handling procedures, problematic side reactions, the use of expensive, toxic and moisture-sensitive reagents, long reaction times, low yields, and environmental concerns associated with the use of poorly manageable catalysts.…”