Hydrogen Bond Control of Active Oxidizing Species in Manganese Porphyrin Hydroxylation Catalysts

نویسندگان

  • Mahdie Saghian Chemistry Department, Shahid Beheshti University, G.C, Evin, Tehran 19839-63113, Iran
  • Nasser Safari Chemistry Department, Shahid Beheshti University, G.C, Evin, Tehran 19839-63113, Iran
  • Tahereh Alemohammad Chemistry Department, Shahid Beheshti University, G.C, Evin, Tehran 19839-63113, Iran
چکیده مقاله:

Some meso-tetra aryl porphyrinato manganese (III) acetate or chloride complexes including meso-tetraphenyl porphyrinato manganese (III) chloride (TPPMnCl), meso-tetrakis(2,3-dimethoxyphenyl)porphyrinato manganese(III) acetate, (T(2,3-OMeP)PMnOAc) and meso-tetrakis(pentaflourophenyl)porphyrinato manganese (III) acetate (TPFPPMnOAc) were synthesized. These porphyrins were used as catalyst in the oxidation of various alkanes in the presence of pyridine and imidazole as axial ligands. It was revealed that the catalytic activity depends on the existence of hydrogen bonding between the axial base and the substituents on the ortho position of the phenyl ring, in addition to usual electronic and steric effects. Therefore, T(2,3-OMeP)PMnOAc and TPFPPMnOAc exhibited higher catalytic activity than TPPMnCl owing to the presence of such hydrogen bonding between substitutions on the periphery of the porphyrin ring and coordinated axial ligand. Also, the selectivity of these two Manganese porphyrins significantly varies in the presence of pyridine and imidazole for the alkane hydroxylation and is reversed for the alkene epoxidation, suggesting different active oxidizing agent produced by pyridine and imidazole.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Manganese and Cobalt Salts of Para-Amino-Benzoic Acid Supported on Silica Gel as Oxidizing Catalysts

Para-Aminobenzoic acid is supported on silica gel via reaction of activated silica gel and p-aminobenzoic acid which is then converted to its manganese and cobalt salts. A mixture of the manganese and cobalt salts of the acid is used to catalyze allylic and benzylic alcohols to their corresponding carbonyl compounds in reasonable yields using oxygen or air. Reactions are clean and the catal...

متن کامل

Spotlight: Porphyrin-based catalysts

< p>Mohammad Dashteh was born in 1994 in Dashteh/ Hamedan, Iran. Having graduated in the field of Pure Chemistry (2016) from Bu-Ali Sina University, Hamedan, Iran, he continued his M.Sc. in 2018 in Organic Chemistry under the supervision of Professor Mohammad Ali Zolfigol. He is currently working towards his Ph.D. under the supervision of Professor Mohammad Ali Zolfigol and Professor Ardeshir K...

متن کامل

Interrupting the hydrogen bond network at the active site of human manganese superoxide dismutase.

Histidine 30 in human manganese superoxide dismutase (MnSOD) is located at a site partially exposed to solvent with its side chain participating in a hydrogen-bonded network that includes the active-site residues Tyr(166) and Tyr(34) and extends to the manganese-bound solvent molecule. We have replaced His(30) with a series of amino acids and Tyr(166) with Phe in human MnSOD. The crystal struct...

متن کامل

Hydrogen-atom abstraction reactions by manganese(V)- and manganese(IV)-oxo porphyrin complexes in aqueous solution.

High-valent manganese(IV or V)-oxo porphyrins are considered as reactive intermediates in the oxidation of organic substrates by manganese porphyrin catalysts. We have generated Mn(V)- and Mn(IV)-oxo porphyrins in basic aqueous solution and investigated their reactivities in C-H bond activation of hydrocarbons. We now report that Mn(V)- and Mn(IV)-oxo porphyrins are capable of activating C-H bo...

متن کامل

manganese and cobalt salts of para-amino-benzoic acid supported on silica gel as oxidizing catalysts

para-aminobenzoic acid is supported on silica gel via reaction of activated silica gel and p-aminobenzoic acid which is then converted to its manganese and cobalt salts. a mixture of the manganese and cobalt salts of the acid is used to catalyze allylic and benzylic alcohols to their corresponding carbonyl compounds in reasonable yields using oxygen or air. reactions are clean and the catalysts...

متن کامل

منابع من

با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ذخیره در منابع من قبلا به منابع من ذحیره شده

{@ msg_add @}


عنوان ژورنال

دوره 2  شماره 1

صفحات  16- 25

تاریخ انتشار 2019-07-01

با دنبال کردن یک ژورنال هنگامی که شماره جدید این ژورنال منتشر می شود به شما از طریق ایمیل اطلاع داده می شود.

میزبانی شده توسط پلتفرم ابری doprax.com

copyright © 2015-2023