Aromatization ring opening

Figure 14. Aromatic ring-opening reactions of a DHP 53 by lignin peroxidase. (The DHP polymer 53 was prepared from 4-ethoxy-3-methoxyphe-nylglycerol-/ -syringaresinol ether 51 and coniferyl alcohol 52.)...

Additionally to phenolic intermediates, upon the aromatic ring opening, a series of carboxylic acids can be formed. Maleic acid, for instance, has been detected in the oxidation of byphenyls (Bouquet-Somrani et al., 1996), 1,2,4-THB (Li et al., 1991a), 1,2-dimethoxybenzene (Pichat, 1997), and acid orange 7 (Stylidi et al., 2003). Similarly, muconic acid has been reported as an intermediate of byphenyls oxidation (Bouquet-Sormani et al., 1996), while succinic and malonic acids were identified in polycarboxylic benzoic acid oxidation (Assabane et al., 2000). It is therefore expected that these or similar acids be formed during phenol oxidation. 

Hexafluorobenzene Detachment of F Aromatic ring opening 1 ablation 2 50 -22 -27 0 -0.05... 

K. Sugimoto, T. Senda, H. Aoshima, E. Masai, M. Fukuda, and Y. Mitsui. 1999. Crystal structure of an aromatic ring opening dioxygenase LigAB, a protocatechuate 4,5-dioxygenase, under aerobic conditions Structure FoldDes. 1 953-965. (PubMed)... 

Figure 9 Coupling of mobility with the glass transition in a polymer system. Mobility is the reciprocal of the correlation time for the type of motion indicated. Correlation times were evaluated from D-NMR relaxation data. (A) Reorientation or fluctuation of the chain axis. (O) Rotation about the chain axis. ( ) the 180° ring flips of side chain aromatic rings. Open and closed symbols refer to different degrees of deuteration. (Reproduced with permission from [4], Original data from [52].)...

Poisoning effect of carbon monoxide for (2a) Grubbs catalyst was reported by J. Diver (Eq. 5). Reaction takes place at ambient temperature and atmospheric pressure with 7V-heteroeyelie earbene (NHC) aromatic ring opening followed with benzylidene insertion [16] ... 

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