Catalytic Oxidation of Alcohols with Ru(Pybox)(Pydic) Complex

Abstract

Primary and secondary alcohols were catalytically oxidized with diacetoxyiodobenzene in the presence of Ru(Pybox)(Pydic) complex to afford the corresponding aldehydes and ketones in high yields.

Ruthenium‐Catalyzed Asymmetric Epoxidation of Olefins Using H2O2, Part II: Catalytic Activities and Mechanism

“…Hence, excellent yield and good ee have been achieved with tertiary alcohols. Use of the secondary alcohol 2-propanol gave a lower ee, since the competitive reaction of oxidation of 2-propanol occurred, [35] which increased the water content of the reaction mixture during the addition of H 2 O 2 . Previously, we have demonstrated that over-dosage of H 2 O in the epoxidation of transstilbene catalyzed by 1 aa with PhI(OAc) 2 as the oxidant also decreased the ee.…”

“…[14] Mono-, Abstract: Asymmetric epoxidation of olefins with 30 % H 2 O 2 in the presence of [Ru(pybox)(pydic)] 1 and [Ru(pyboxazine)(pydic)] 2 has been studied in detail (pybox = pyridine-2,6-bisoxazoline, pyboxazine = pyridine-2,6-bisoxazine, pydic = 2,6-pyridinedicarboxylate). 35 Ruthenium complexes with sterically and electronically different substituents have been tested in environmentally benign epoxidation reactions. Mono-, 1,1-di-, cis-and trans-1,2-di-, tri-, and tetra-substituted aromatic olefins with versatile functional groups can be epoxidized with this type of catalyst in good to excellent yields (up to 100 %) with moderate to good enantioselectivies (up to 84 % ee).…”

An improved protocol for the ruthenium(pybox)-catalyzed asymmetric alkene epoxidation

“…2,6-Di(hydroxymethyl)pyridine revealed to be a viable co-ligand candidate, possibly due to the formation of 2,6-pyridinedicarboxylic acid by oxidation ( Table 2, entry 4). 7 On the other hand, commercially available 2,6-pyridinebisoxazolines showed very good reactivities (Table 2, entries 1, 11 and 12). Here, the i Pr-substituted pybox gave the best enantioselectivity, while the phenyl-substituted derivative showed the best reactivity.…”

Catalytic Action of Triarylstibanes: Oxidation of Benzoins into Benzyls Using Triarylstibanes Under an Aerobic Condition

“…[1][2][3][4][5] As for the application of trivalent organoantimony compounds (stibanes), a wide variety of reactions such as self-coupling reactions, 6,7) cross-coupling reactions, [8][9][10][11][12][13] photoreaction, 14) and asymmetric reactions with optically active organoantimony compounds [15][16][17][18][19] have been reported during the last two decades. On the other hand, the conversion of benzoin into benzil has been accomplished by oxidation with a variety of reagents; i.e., bismuthane oxide, 20) bismuthane imides, 21) alumina-supported copper sulfate under microwave irradiation, 22) and the Burgess reagent, 23) and by transition metal-catalyzed oxidation with bismuth nitrate-copper acetate, 24) aerobic oxygen, 25,26) diacetoxyiodobenzene, 27) and allyl diethyl phosphate. 28) In this respect, pentavalent antimony compounds such as stibane oxide, 20) diacetoxytriphenystiborane, 29) dibromotriphenylstiborane, 30,31) and stibane imides 21) were also known to be effective for this reaction.…”