A qualitative molecular orbital rationalization of the selectivities in ortho, meta, and cycloadditions of singlet excited states of substituted benzenes to alkenes, and of triplet state di—ir—methane rearrangements of substituted benzonorbornadienes is presented. As the name suggests, excited states of benzene and substituted benzenes are prone to aroused reactivity tendencies, rearranging to ...

Aryne intermediates are versatile and important reactive intermediates for natural product and polymer synthesis. 2-Naphthynes are relatively unexplored because few methods provide precursors to these intermediates, especially for those bearing additional substituents. Here we report a general synthetic strategy to access 2-naphthyne precursors through an Asao-Yamamoto benzannulation of ortho-(...

Under secondary metabolic conditions, the white-rot basidiomycete Phanerochaete chrysosporium degraded 2,7-dichlorodibenzo-p-dioxin (I). The pathway for the degradation of I was elucidated by the characterization of fungal metabolites and oxidation products generated by lignin peroxidase (LiP), manganese peroxidase (MnP), and crude intracellular cell-free extracts. The multistep pathway involve...

henols and phenolic substances are aromatic hydroxy compounds classified as monohydric (e.g., phenol, cresols [methylphenols], xylenols [dimethylphenols]), dihydric (e.g., catechols [odihydroxybenzenes], resorcinols [m-dihydroxybenzenes]) or polyhydric (with three or more hydroxy groups), depending on the number of hydroxyl groups attached to the aromatic benzene ring (McNeely et al. 1979). The...

Mixed matrix membranes (MMMs) have been obtained by blending an aromatic ortho-hydroxypolyimide (PIOH) or ortho-acetylpolyimide (PIOAc) with different loading amounts (15 and 30 wt %) of a microporous polymer network (PPN), which was from the reaction triptycene isatin. The excellent thermal resistance PPN (above 500 °C) allowed it to be used as filler successfully prepare thermally rearranged ...

Streptomyces setonii (ATCC 39116) is a thermophilic soil actinomycete capable of degrading single aromatic compounds including phenol and benzoate via the ortho-cleavage pathway. Previously, a 6.3-kb S. setonii DNA fragment containing a thermophilic catechol 1,2-dioxygenase (C12O) gene was isolated and functionally overexpressed in Escherichia coli (An et al., FEMS Microbiol. Lett. 195 (2001) 1...