Low‐Molecular‐Weight Analogues of the Soluble Methane Monooxygenase (sMMO): From the Structural Mimicking of Resting States and Intermediates to Functional Models

Abstract

The active centre of sMMO contains a diiron core ligated by histidine and glutamate residues, which is capable of catalysing a remarkable reaction: the oxidation of methane with O(2) yielding methanol. This review describes the results of efforts to prepare low-molecular-weight analogues of this active site directing towards 1) the assignment of the spectroscopic signatures identified for certain intermediates of the sMMO catalytic cycle to structural features and 2) the synthesis of molecular compounds that can mimic the reactivity. The historical development of the model chemistry, which is subdivided into structural and functional mimicking, is illustrated and achievements reached so far are highlighted.

Trinuclear Non‐Heme Iron Complexes Based on 4‐Substituted 2,6‐Diacylpyridine Ligands as Catalysts in Aerobic Allylic Oxidations

“…(5)); 7.42 -7.45 (m, HÀC(3''), HÀC(5'')); 7.52 -7.55 (m, HÀC(2''), HÀC(6'')). 13 C-NMR (125 MHz, CDCl 3 ): 32.8, 32.9 (C(1'), C(2')); 51.6 (Me); 118.4 (C(3), C(5)); 128.3, 129.2 (C(2''), C(6''), C(3''), C(5'')); 135.0 (C(4'')); 137.1 (C(1'')); 147.9 (C(4)); 160.0 (C(2), C(6)); 173.7 (C¼O). ESI-MS: 384.1 (…”

“…(5)); 7.37 -7.48 (m, HÀC(3''), HÀC(5'')); 7.58 -7.65 (m, HÀC(2''), HÀC(6'')). 13 C-NMR (125 MHz, (D 6 )DMSO): 33.1, 33.8 (C(1'), C(2')); 118.9 (C(3), C(5)); 129.3, 129.6 (C(2''), C(6''), C(3''), C(5'')); 135.9 (C(4'')); 137.7 (C(1'')); 148.2 (C(4)); 160.3 (C(2), C (6) 1 H-NMR (500 MHz, (D 6 )DMSO): 2.62 (t, J ¼ 7.5, 2 CH 2 (2'')); 2.88 (t, J ¼ 7.5, 2 CH 2 (1'')); 5.12 (s, CH 2 O)); 6.77 (s, HÀC(3), HÀC(5)); 7.41 -7.42 (m, 2 H of HÀC(2'), HÀC(6'), HÀC(3'), HÀC(5')); 7.59 -7.61 (m, 2 H of HÀC(2'), HÀC(6'), HÀC(3'), HÀC(5')). 1'')); 32.7 (C(2'')); 68.2 (C(7)); 106.9 (C(3), C(5)); 121.2 (C(4')); 128.5, 129.9 (C(2'), C(6'), C(3'), C(5')); 135.7 (C(1')); 160.9 (C(2), C(6)); 164.9 (C(4)); 173.9 (C¼O).…”

“…ESI-MS: (2'), HÀC(6'), HÀC(3'), HÀC(5')); 7.55 -7.56 (m, 2 H of HÀC(2'), HÀC(6'), HÀC(3'), HÀC(5')); 7.88 (s, HÀC(3), HÀC(5)). 13 C-NMR (125 MHz, CDCl 3 ): 53.4 (MeO); 70.0 (CH 2 O); 114.8 (C(3), C(5)); 122.9 (C(4')); 129.3, 132.1 (C(2'), C(6'), C(3'), C(5')); 133.7 (C(1')); 149.9 (C(2), C(6)); 165.1 (C¼O); 166.5 (C(4)). ESI-MS: (5)); 7.37 -7.40 (m, 2 H of HÀC(2'), HÀC(6'), HÀC(3'), HÀC(5')); 7.55 -7.58 (m, 2 H of HÀC(2'), HÀC(6'), HÀC(3'), HÀC(5')).…”

“…IR (ATR): 3066, 2951, 2846, 1731, 1647, 1563, 1435, 1365, 1301, 1247, 1195, 1160, 1031, 986, 883 (1')); 7.89 (s, HÀC(3), HÀC(5)). 13 (5)). (5)); 7.37 -7.48 (m, HÀC(3''), HÀC(5'')); 7.58 -7.65 (m, HÀC(2''), HÀC(6'')).…”

“…(5)); 7.59 (d, J ¼ 15.6, 2 HÀC(1')). 13 C-NMR (125 MHz, CDCl 3 ): 52.0 (MeO); 124.2 (C(2')); 127.5 (C(3), C(5)); 134.0 (C(4)); 141.6 (C(1')); 154.1 (C(2), C(6)); 166.7 (C¼O). GC/EI-MS: 328 (5)); 7.0 (d, J ¼ 15.5, 2 HÀC(2'')); 7.29 -7.30 (m, HÀC(2'), HÀC(6') or HÀC(3'), HÀC(5')); 7.54 -7.56 (m, HÀC(3'), HÀC(5') or HÀC(2'), HÀC(6')); 7.6 (d, J ¼ 15.5, 2 HÀC(1'')).…”