Mixed Picolinate and Quinaldinate Iron(III) Complexes for the Catalytic Oxidation of Alcohols with Hydrogen Peroxide

Abstract

A series of Fe mixed picolinate and quinaldinate complexes that catalyze the H2O2 oxidation of alcohols are presented. The Fe catalysts are generated in situ by simple mixing of iron acetate with 6‐methylpicolinic acid (6‐MepicH) and 4‐chloropicolinic acid (4‐ClpicH); they showed high catalytic activity for H2O2 oxidation of 1‐phenylethanol to acetophenone. Fe complexes generated in situ as precatalysts were successfully isolated and structurally characterized. Based on the single‐crystal X‐ray analysis and electrochemical measurements of the Fe complexes, the lability of picolinate and/or quinaldinate ligand and the redox potential of FeIII were found to be important factors for the catalytic reaction.

Recent Advances in Iron Catalyzed Oxidation Reactions of Organic Compounds

“…Primary alcohols are oxidized to the corresponding carboxylic acids in isolated yields up to 99 % (entry 1). A mixture of Fe(OAc) 2 , picolinic acid and 4‐substituted picolinic acids was demonstrated by Sato to be catalytically active in the oxidation of secondary alcohols to the corresponding ketones utilizing H 2 O 2 ; an example is given in entry 2 . Sato also reported the selective oxidation of α,β‐unsaturated aldehydes to α,β‐unsaturated carboxylic acids utilizing molecular oxygen and Fe(NO 3 ) 3 ⋅9H 2 O as the catalyst …”

Copolymeric Schiff Base Cu: A Platform for Active and Recyclable Catalyst in Aerobic Oxidations

“…The catalytic evaluation of the hetero-SchCu catalyst started from the oxidation of alcohols, which is an important reaction for the production of valuable ketones and aldehydes. , Conventionally, perchlorate, nitric acid, and potassium permanganate were employed as oxidants, which are high cost and environmentally unfriendly. , Herein, we evaluated the catalysts using hydrogen peroxide as the oxygen donor, which is regarded to be a green oxidant with water as the sole product. , As presented in the oxidation of benzyl alcohol in Table , the blank run without any catalyst failed to catalyze the transformation of benzyl alcohol (entry 1). CuCl 2 , CuO, and Cu 2 O are active for the oxidation of benzyl alcohol to benzaldehyde as major products (entries 3–5), but exhibit low conversions at 1.9%, 9.2%, and 13.9%, respectively.…”

“…31,32 Herein, we evaluated the catalysts using hydrogen peroxide as the oxygen donor, which is regarded to be a green oxidant with water as the sole product. 33,34 As presented in the oxidation of benzyl alcohol in Table 1, the blank run without any catalyst failed to catalyze the transformation of benzyl alcohol (entry 1). CuCl 2 , CuO, and Cu 2 O are active for the oxidation of benzyl alcohol to benzaldehyde as major products (entries 3−5), but exhibit low conversions at 1.9%, 9.2%, and 13.9%, respectively.…”

Alcohol oxidation with H2O2 catalyzed by a cheap and promptly available imine based iron complex

“…6 Indeed, aminopyridine iron complexes have been recently demonstrated to promote effective and highly selective oxidation reactions, mimicking natural nonheme iron oxygenases. [7][8][9][10][11][12][13][14] Iron-catalyzed alcohol oxidation with H 2 O 2 has been first explored by Beller and coworkers, [15][16][17][18] and in the last decade several iron complexes have been reported to mediate alcohol oxidation with H 2 O 2 [19][20][21][22][23][24][25] or t-BuOOH. 26 Also manganese-based catalysts in combination with H 2 O 2 provided promising results in alcohol oxidation.…”